Complete rework of PID demo and underlying devices

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/ConstructorElement.kt

@@ -3,11 +3,13 @@ package space.kscience.controls.constructor
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.flow.*
+import kotlinx.datetime.Instant
 import space.kscience.controls.api.Device
 import space.kscience.controls.manager.ClockManager
 import space.kscience.dataforge.context.ContextAware
 import space.kscience.dataforge.context.request
 import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
 
 /**
  * A binding that is used to describe device functionality
@@ -36,7 +38,7 @@ public class ConnectionConstrucorElement(
 ) : ConstructorElement
 
 public class ModelConstructorElement(
-    public val model: ConstructorModel
+    public val model: ModelConstructor,
 ) : ConstructorElement
 
 
@@ -77,19 +79,19 @@ public interface StateContainer : ContextAware, CoroutineScope {
 /**
  * Register a [state] in this container. The state is not registered as a device property if [this] is a [DeviceConstructor]
  */
-public fun <T, D : DeviceState<T>> StateContainer.state(state: D): D {
+public fun <T, D : DeviceState<T>> StateContainer.registerState(state: D): D {
     registerElement(StateConstructorElement(state))
     return state
 }
 
 /**
- * Create a register a [MutableDeviceState] with a given [converter]
+ * Create a register a [MutableDeviceState]
  */
-public fun <T> StateContainer.stateOf(initialValue: T): MutableDeviceState<T> = state(
+public fun <T> StateContainer.stateOf(initialValue: T): MutableDeviceState<T> = registerState(
     MutableDeviceState(initialValue)
 )
 
-public fun <T : ConstructorModel> StateContainer.model(model: T): T {
+public fun <T : ModelConstructor> StateContainer.model(model: T): T {
     registerElement(ModelConstructorElement(model))
     return model
 }
@@ -97,23 +99,53 @@ public fun <T : ConstructorModel> StateContainer.model(model: T): T {
 /**
  * Create and register a timer state.
  */
-public fun StateContainer.timer(tick: Duration): TimerState = state(TimerState(context.request(ClockManager), tick))
+public fun StateContainer.timer(tick: Duration): TimerState =
+    registerState(TimerState(context.request(ClockManager), tick))
 
+/**
+ * Register a new timer and perform [block] on its change
+ */
+public fun StateContainer.onTimer(
+    tick: Duration,
+    writes: Collection<DeviceState<*>> = emptySet(),
+    reads: Collection<DeviceState<*>> = emptySet(),
+    block: suspend (prev: Instant, next: Instant) -> Unit,
+): Job = timer(tick).onChange(writes = writes, reads = reads, onChange = block)
+
+public enum class DefaultTimer(public val duration: Duration){
+    REALTIME(5.milliseconds),
+    VERY_FAST(10.milliseconds),
+    FAST(20.milliseconds),
+    MEDIUM(50.milliseconds),
+    SLOW(100.milliseconds),
+    VERY_SLOW(500.milliseconds),
+}
+
+/**
+ * Perform an action on default timer
+ */
+public fun StateContainer.onTimer(
+    defaultTimer: DefaultTimer = DefaultTimer.FAST,
+    writes: Collection<DeviceState<*>> = emptySet(),
+    reads: Collection<DeviceState<*>> = emptySet(),
+    block: suspend (prev: Instant, next: Instant) -> Unit,
+): Job = timer(defaultTimer.duration).onChange(writes = writes, reads = reads, onChange = block)
+//TODO implement timer pooling
 
 public fun <T, R> StateContainer.mapState(
     origin: DeviceState<T>,
     transformation: (T) -> R,
-): DeviceStateWithDependencies<R> = state(DeviceState.map(origin, transformation))
+): DeviceStateWithDependencies<R> = registerState(DeviceState.map(origin, transformation))
 
 
 public fun <T, R> StateContainer.flowState(
     origin: DeviceState<T>,
     initialValue: R,
-    transformation: suspend FlowCollector<R>.(T) -> Unit
+    transformation: suspend FlowCollector<R>.(T) -> Unit,
 ): DeviceStateWithDependencies<R> {
     val state = MutableDeviceState(initialValue)
     origin.valueFlow.transform(transformation).onEach { state.value = it }.launchIn(this)
-    return state(state.withDependencies(setOf(origin)))
+    return registerState(state.withDependencies(setOf(origin)))
 }
 
 /**
@@ -123,8 +155,7 @@ public fun <T1, T2, R> StateContainer.combineState(
     first: DeviceState<T1>,
     second: DeviceState<T2>,
     transformation: (T1, T2) -> R,
-): DeviceState<R> = state(DeviceState.combine(first, second, transformation))
+): DeviceState<R> = registerState(DeviceState.combine(first, second, transformation))
-
 
 /**
  * Create and start binding between [sourceState] and [targetState]. Changes made to [sourceState] are automatically
@@ -132,7 +163,7 @@ public fun <T1, T2, R> StateContainer.combineState(
  *
  * On resulting [Job] cancel the binding is unregistered
  */
-public fun <T> StateContainer.bindTo(sourceState: DeviceState<T>, targetState: MutableDeviceState<T>): Job {
+public fun <T> StateContainer.bind(sourceState: DeviceState<T>, targetState: MutableDeviceState<T>): Job {
     val descriptor = ConnectionConstrucorElement(setOf(sourceState), setOf(targetState))
     registerElement(descriptor)
     return sourceState.valueFlow.onEach {

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/DeviceConstructor.kt

@@ -32,13 +32,14 @@ public abstract class DeviceConstructor(
         _constructorElements.remove(constructorElement)
     }
 
-    override fun <T> registerProperty(
+    override fun <T, S: DeviceState<T>> registerAsProperty(
         converter: MetaConverter<T>,
         descriptor: PropertyDescriptor,
-        state: DeviceState<T>,
+        state: S,
-    ) {
+    ): S {
-        super.registerProperty(converter, descriptor, state)
+        val res = super.registerAsProperty(converter, descriptor, state)
         registerElement(PropertyConstructorElement(this, descriptor.name, state))
+        return res
     }
 }
 
@@ -83,7 +84,7 @@ public fun <T, S : DeviceState<T>> DeviceConstructor.property(
     PropertyDelegateProvider { _: DeviceConstructor, property ->
         val name = nameOverride ?: property.name
         val descriptor = PropertyDescriptor(name).apply(descriptorBuilder)
-        registerProperty(converter, descriptor, state)
+        registerAsProperty(converter, descriptor, state)
         ReadOnlyProperty { _: DeviceConstructor, _ ->
             state
         }
@@ -140,7 +141,10 @@ public fun <T> DeviceConstructor.virtualProperty(
     nameOverride,
 )
 
-public fun <T, S : DeviceState<T>> DeviceConstructor.property(
+public fun <T, S : DeviceState<T>> DeviceConstructor.registerAsProperty(
     spec: DevicePropertySpec<*, T>,
     state: S,
-): Unit = registerProperty(spec.converter, spec.descriptor, state)
+): S {
+    registerAsProperty(spec.converter, spec.descriptor, state)
+    return state
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/DeviceGroup.kt

@@ -93,11 +93,11 @@ public open class DeviceGroup(
     /**
      * Register a new property based on [DeviceState]. Properties could be modified dynamically
      */
-    public open fun <T> registerProperty(
+    public open fun <T, S : DeviceState<T>> registerAsProperty(
         converter: MetaConverter<T>,
         descriptor: PropertyDescriptor,
-        state: DeviceState<T>,
+        state: S,
-    ) {
+    ): S {
         val name = descriptor.name.parseAsName()
         require(properties[name] == null) { "Can't add property with name $name. It already exists." }
         properties[name] = Property(state, converter, descriptor)
@@ -109,6 +109,7 @@ public open class DeviceGroup(
                 )
             )
         }.launchIn(this)
+        return state
     }
 
     private val actions: MutableMap<Name, Action> = hashMapOf()
@@ -174,8 +175,8 @@ public open class DeviceGroup(
     }
 }
 
-public fun <T> DeviceGroup.registerProperty(propertySpec: DevicePropertySpec<*, T>, state: DeviceState<T>) {
+public fun <T> DeviceGroup.registerAsProperty(propertySpec: DevicePropertySpec<*, T>, state: DeviceState<T>) {
-    registerProperty(propertySpec.converter, propertySpec.descriptor, state)
+    registerAsProperty(propertySpec.converter, propertySpec.descriptor, state)
 }
 
 public fun DeviceManager.registerDeviceGroup(
@@ -246,13 +247,13 @@ public fun DeviceGroup.registerDeviceGroup(name: String, block: DeviceGroup.() -
 /**
  * Register read-only property based on [state]
  */
-public fun <T : Any> DeviceGroup.registerProperty(
+public fun <T : Any> DeviceGroup.registerAsProperty(
     name: String,
     converter: MetaConverter<T>,
     state: DeviceState<T>,
     descriptorBuilder: PropertyDescriptor.() -> Unit = {},
 ) {
-    registerProperty(
+    registerAsProperty(
         converter,
         PropertyDescriptor(name).apply(descriptorBuilder),
         state
@@ -268,7 +269,7 @@ public fun <T : Any> DeviceGroup.registerMutableProperty(
     state: MutableDeviceState<T>,
     descriptorBuilder: PropertyDescriptor.() -> Unit = {},
 ) {
-    registerProperty(
+    registerAsProperty(
         converter,
         PropertyDescriptor(name).apply(descriptorBuilder),
         state

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/DeviceState.kt

@@ -6,12 +6,14 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onEach
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.UnitsOfMeasurement
 import kotlin.reflect.KProperty
 
 /**
  * An observable state of a device
  */
-public interface DeviceState<T> {
+public interface DeviceState<out T> {
     public val value: T
 
     public val valueFlow: Flow<T>
@@ -49,7 +51,7 @@ public interface DeviceStateWithDependencies<T> : DeviceState<T> {
 }
 
 public fun <T> DeviceState<T>.withDependencies(
-    dependencies: Collection<DeviceState<*>>
+    dependencies: Collection<DeviceState<*>>,
 ): DeviceStateWithDependencies<T> = object : DeviceStateWithDependencies<T>, DeviceState<T> by this {
     override val dependencies: Collection<DeviceState<*>> = dependencies
 }
@@ -67,7 +69,19 @@ public fun <T, R> DeviceState.Companion.map(
 
     override val valueFlow: Flow<R> = state.valueFlow.map(mapper)
 
-    override fun toString(): String = "DeviceState.map(arg=${state})"
+    override fun toString(): String = "DeviceState.map(state=${state})"
+}
+
+public fun <T, R> DeviceState<T>.map(mapper: (T) -> R): DeviceStateWithDependencies<R> = DeviceState.map(this, mapper)
+
+public fun DeviceState<out NumericalValue<out UnitsOfMeasurement>>.values(): DeviceState<Double> = object : DeviceState<Double> {
+    override val value: Double
+        get() = this@values.value.value
+
+    override val valueFlow: Flow<Double>
+        get() = this@values.valueFlow.map { it.value }
+
+    override fun toString(): String = this@values.toString()
 }
 
 /**

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/ModelConstructor.kt

@@ -6,7 +6,7 @@ import kotlinx.coroutines.newCoroutineContext
 import space.kscience.dataforge.context.Context
 import kotlin.coroutines.CoroutineContext
 
-public abstract class ConstructorModel(
+public abstract class ModelConstructor(
     final override val context: Context,
     vararg dependencies: DeviceState<*>,
 ) : StateContainer, CoroutineScope {

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/devices/Drive.kt

@@ -0,0 +1,18 @@
+package space.kscience.controls.constructor.devices
+
+import space.kscience.controls.constructor.DeviceConstructor
+import space.kscience.controls.constructor.MutableDeviceState
+import space.kscience.controls.constructor.property
+import space.kscience.controls.constructor.units.NewtonsMeters
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.numerical
+import space.kscience.dataforge.context.Context
+import space.kscience.dataforge.meta.MetaConverter
+
+
+public class Drive(
+    context: Context,
+    force: MutableDeviceState<NumericalValue<NewtonsMeters>> = MutableDeviceState(NumericalValue(0)),
+) : DeviceConstructor(context) {
+    public val force: MutableDeviceState<NumericalValue<NewtonsMeters>> by property(MetaConverter.numerical(), force)
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/devices/EncoderDevice.kt

@@ -0,0 +1,20 @@
+package space.kscience.controls.constructor.devices
+
+import space.kscience.controls.constructor.DeviceConstructor
+import space.kscience.controls.constructor.DeviceState
+import space.kscience.controls.constructor.property
+import space.kscience.controls.constructor.units.Degrees
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.numerical
+import space.kscience.dataforge.context.Context
+import space.kscience.dataforge.meta.MetaConverter
+
+/**
+ * An encoder that can read an angle
+ */
+public class EncoderDevice(
+    context: Context,
+    position: DeviceState<NumericalValue<Degrees>>
+) : DeviceConstructor(context) {
+    public val position: DeviceState<NumericalValue<Degrees>> by property(MetaConverter.numerical<Degrees>(), position)
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/devices/LimitSwitch.kt

@@ -0,0 +1,44 @@
+package space.kscience.controls.constructor.devices
+
+import space.kscience.controls.constructor.DeviceConstructor
+import space.kscience.controls.constructor.DeviceState
+import space.kscience.controls.constructor.map
+import space.kscience.controls.constructor.registerAsProperty
+import space.kscience.controls.constructor.units.Direction
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.UnitsOfMeasurement
+import space.kscience.controls.spec.DevicePropertySpec
+import space.kscience.controls.spec.DeviceSpec
+import space.kscience.controls.spec.booleanProperty
+import space.kscience.dataforge.context.Context
+
+
+/**
+ * Virtual [LimitSwitch]
+ */
+public class LimitSwitch(
+    context: Context,
+    locked: DeviceState<Boolean>,
+) : DeviceConstructor(context) {
+
+    public val locked: DeviceState<Boolean> = registerAsProperty(LimitSwitch.locked, locked)
+
+    public companion object : DeviceSpec<LimitSwitch>() {
+        public val locked: DevicePropertySpec<LimitSwitch, Boolean> by booleanProperty { locked.value }
+    }
+}
+
+public fun <U : UnitsOfMeasurement, T : NumericalValue<U>> LimitSwitch(
+    context: Context,
+    limit: T,
+    boundary: Direction,
+    position: DeviceState<T>,
+): LimitSwitch = LimitSwitch(
+    context,
+    DeviceState.map(position) {
+        when (boundary) {
+            Direction.UP -> it >= limit
+            Direction.DOWN -> it <= limit
+        }
+    }
+)

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/devices/LinearDrive.kt

@@ -0,0 +1,38 @@
+package space.kscience.controls.constructor.devices
+
+import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.models.PidParameters
+import space.kscience.controls.constructor.models.PidRegulator
+import space.kscience.controls.constructor.units.Meters
+import space.kscience.controls.constructor.units.NewtonsMeters
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.numerical
+import space.kscience.dataforge.context.Context
+import space.kscience.dataforge.meta.Meta
+import space.kscience.dataforge.meta.MetaConverter
+
+public class LinearDrive(
+    drive: Drive,
+    start: LimitSwitch,
+    end: LimitSwitch,
+    position: DeviceState<NumericalValue<Meters>>,
+    pidParameters: PidParameters,
+    context: Context = drive.context,
+    meta: Meta = Meta.EMPTY,
+) : DeviceConstructor(context, meta) {
+
+    public val position: DeviceState<NumericalValue<Meters>> by property(MetaConverter.numerical(), position)
+
+    public val drive: Drive by device(drive)
+    public val pid: PidRegulator<Meters, NewtonsMeters>  = model(
+        PidRegulator(
+            context = context,
+            position = position,
+            output = drive.force,
+            pidParameters = pidParameters
+        )
+    )
+
+    public val startLimit: LimitSwitch by device(start)
+    public val endLimit: LimitSwitch by device(end)
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/devices/StepDrive.kt

@@ -0,0 +1,61 @@
+package space.kscience.controls.constructor.devices
+
+import kotlinx.coroutines.launch
+import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.units.Degrees
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.plus
+import space.kscience.controls.constructor.units.times
+import space.kscience.dataforge.context.Context
+import space.kscience.dataforge.meta.MetaConverter
+import kotlin.math.max
+import kotlin.math.min
+import kotlin.math.roundToInt
+import kotlin.time.DurationUnit
+
+/**
+ * A step drive
+ *
+ * @param speed ticks per second
+ * @param target target ticks state
+ * @param writeTicks a hardware callback
+ */
+public class StepDrive(
+    context: Context,
+    speed: MutableDeviceState<Double>,
+    target: MutableDeviceState<Int> = MutableDeviceState(0),
+    private val writeTicks: suspend (ticks: Int, speed: Double) -> Unit,
+) : DeviceConstructor(context) {
+
+    public val target: MutableDeviceState<Int> by property(MetaConverter.int, target)
+
+    public val speed: MutableDeviceState<Double> by property(MetaConverter.double, speed)
+
+    private val positionState = stateOf(target.value)
+
+    public val position: DeviceState<Int> by property(MetaConverter.int, positionState)
+
+    private val ticker = onTimer { prev, next ->
+        val tickSpeed = speed.value
+        val timeDelta = (next - prev).toDouble(DurationUnit.SECONDS)
+        val ticksDelta: Int = target.value - position.value
+        val steps: Int = when {
+            ticksDelta > 0 -> min(ticksDelta, (timeDelta * tickSpeed).roundToInt())
+            ticksDelta < 0 -> max(ticksDelta, (timeDelta * tickSpeed).roundToInt())
+            else -> return@onTimer
+        }
+        launch {
+            writeTicks(steps, tickSpeed)
+            positionState.value += steps
+        }
+    }
+}
+
+/**
+ * Compute a state using given tick-to-angle transformation
+ */
+public fun StepDrive.angle(
+    zero: NumericalValue<Degrees>,
+    step: NumericalValue<Degrees>,
+): DeviceState<NumericalValue<Degrees>> = position.map { zero + it * step }
+

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/exoticState.kt

@@ -1,57 +0,0 @@
-package space.kscience.controls.constructor
-
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.StateFlow
-
-
-/**
- *  A state describing a [Double] value in the [range]
- */
-public class DoubleInRangeState(
-    initialValue: Double,
-    public val range: ClosedFloatingPointRange<Double>,
-) : MutableDeviceState<Double> {
-
-    init {
-        require(initialValue in range) { "Initial value should be in range" }
-    }
-
-
-    private val _valueFlow = MutableStateFlow(initialValue)
-
-    override var value: Double
-        get() = _valueFlow.value
-        set(newValue) {
-            _valueFlow.value = newValue.coerceIn(range)
-        }
-
-    override val valueFlow: StateFlow<Double> get() = _valueFlow
-
-    /**
-     * A state showing that the range is on its lower boundary
-     */
-    public val atStart: DeviceState<Boolean> = DeviceState.map(this) {
-        it <= range.start
-    }
-
-    /**
-     * A state showing that the range is on its higher boundary
-     */
-    public val atEnd: DeviceState<Boolean> = DeviceState.map(this) {
-        it >= range.endInclusive
-    }
-
-    override fun toString(): String = "DoubleRangeState(range=$range)"
-
-
-}
-
-/**
- * Create and register a [DoubleInRangeState]
- */
-public fun StateContainer.doubleInRangeState(
-    initialValue: Double,
-    range: ClosedFloatingPointRange<Double>,
-): DoubleInRangeState = DoubleInRangeState(initialValue, range).also {
-    registerElement(StateConstructorElement(it))
-}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/internalState.kt

@@ -2,6 +2,7 @@ package space.kscience.controls.constructor
 
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.emptyFlow
 
 /**
  * A [MutableDeviceState] that does not correspond to a physical state
@@ -35,3 +36,18 @@ public fun <T> MutableDeviceState(
     initialValue: T,
     callback: (T) -> Unit = {},
 ): MutableDeviceState<T> = VirtualDeviceState(initialValue, callback)
+
+
+/**
+ * Create a [DeviceState] with constant value
+ */
+public fun <T> DeviceState(
+    value: T
+): DeviceState<T> = object : DeviceState<T> {
+    override val value: T get() = value
+    override val valueFlow: Flow<T>
+        get() = emptyFlow()
+
+    override fun toString(): String = "ConstDeviceState($value)"
+
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/library/Converter.kt

@@ -1,20 +0,0 @@
-package space.kscience.controls.constructor.library
-
-import kotlinx.coroutines.flow.FlowCollector
-import space.kscience.controls.constructor.DeviceConstructor
-import space.kscience.controls.constructor.DeviceState
-import space.kscience.controls.constructor.DeviceStateWithDependencies
-import space.kscience.controls.constructor.flowState
-import space.kscience.dataforge.context.Context
-
-/**
- * A device that converts one type of physical quantity to another type
- */
-public class Converter<T, R>(
-    context: Context,
-    input: DeviceState<T>,
-    initialValue: R,
-    transform: suspend FlowCollector<R>.(T) -> Unit,
-) : DeviceConstructor(context) {
-    public val output: DeviceStateWithDependencies<R> = flowState(input, initialValue, transform)
-}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/library/Drive.kt

@@ -1,101 +0,0 @@
-package space.kscience.controls.constructor.library
-
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.delay
-import kotlinx.coroutines.isActive
-import kotlinx.coroutines.launch
-import space.kscience.controls.api.Device
-import space.kscience.controls.constructor.MutableDeviceState
-import space.kscience.controls.constructor.propertyAsState
-import space.kscience.controls.manager.clock
-import space.kscience.controls.spec.*
-import space.kscience.dataforge.context.Context
-import space.kscience.dataforge.context.Factory
-import space.kscience.dataforge.meta.MetaConverter
-import space.kscience.dataforge.meta.double
-import space.kscience.dataforge.meta.get
-import kotlin.math.pow
-import kotlin.time.Duration.Companion.milliseconds
-import kotlin.time.DurationUnit
-
-/**
- * A classic drive regulated by force with encoder
- */
-public interface Drive : Device {
-    /**
-     * Get or set drive force or momentum
-     */
-    public var force: Double
-
-    /**
-     * Current position value
-     */
-    public val position: Double
-
-    public companion object : DeviceSpec<Drive>() {
-        public val force: MutableDevicePropertySpec<Drive, Double> by Drive.mutableProperty(
-            MetaConverter.double,
-            Drive::force
-        )
-
-        public val position: DevicePropertySpec<Drive, Double> by doubleProperty { position }
-    }
-}
-
-/**
- * A virtual drive
- */
-public class VirtualDrive(
-    context: Context,
-    private val mass: Double,
-    public val positionState: MutableDeviceState<Double>,
-) : Drive, DeviceBySpec<Drive>(Drive, context) {
-
-    private val dt = meta["time.step"].double?.milliseconds ?: 5.milliseconds
-    private val clock = context.clock
-
-    override var force: Double = 0.0
-
-    override val position: Double get() = positionState.value
-
-    public var velocity: Double = 0.0
-        private set
-
-    private var updateJob: Job? = null
-
-    override suspend fun onStart() {
-        updateJob = launch {
-            var lastTime = clock.now()
-            while (isActive) {
-                delay(dt)
-                val realTime = clock.now()
-                val dtSeconds = (realTime - lastTime).toDouble(DurationUnit.SECONDS)
-
-                //set last time and value to new values
-                lastTime = realTime
-
-                // compute new value based on velocity and acceleration from the previous step
-                positionState.value += velocity * dtSeconds + force / mass * dtSeconds.pow(2) / 2
-                propertyChanged(Drive.position, positionState.value)
-
-                // compute new velocity based on acceleration on the previous step
-                velocity += force / mass * dtSeconds
-            }
-        }
-    }
-
-    override suspend fun onStop() {
-        updateJob?.cancel()
-    }
-
-    public companion object {
-        public fun factory(
-            mass: Double,
-            positionState: MutableDeviceState<Double>,
-        ): Factory<Drive> = Factory { context, _ ->
-            VirtualDrive(context, mass, positionState)
-        }
-    }
-}
-
-public suspend fun Drive.stateOfForce(): MutableDeviceState<Double> = propertyAsState(Drive.force)

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/library/LimitSwitch.kt

@@ -1,37 +0,0 @@
-package space.kscience.controls.constructor.library
-
-import space.kscience.controls.api.Device
-import space.kscience.controls.constructor.DeviceConstructor
-import space.kscience.controls.constructor.DeviceState
-import space.kscience.controls.constructor.property
-import space.kscience.controls.spec.DevicePropertySpec
-import space.kscience.controls.spec.DeviceSpec
-import space.kscience.controls.spec.booleanProperty
-import space.kscience.dataforge.context.Context
-import space.kscience.dataforge.meta.MetaConverter
-
-
-/**
- * A limit switch device
- */
-public interface LimitSwitch : Device {
-
-    public fun isLocked(): Boolean
-
-    public companion object : DeviceSpec<LimitSwitch>() {
-        public val locked: DevicePropertySpec<LimitSwitch, Boolean> by booleanProperty { isLocked() }
-    }
-}
-
-/**
- * Virtual [LimitSwitch]
- */
-public class VirtualLimitSwitch(
-    context: Context,
-    locked: DeviceState<Boolean>,
-) : DeviceConstructor(context), LimitSwitch {
-
-    public val locked: DeviceState<Boolean> by property(MetaConverter.boolean, locked)
-
-    override fun isLocked(): Boolean = locked.value
-}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/library/PidRegulator.kt

@@ -1,87 +0,0 @@
-package space.kscience.controls.constructor.library
-
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.delay
-import kotlinx.coroutines.isActive
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.sync.Mutex
-import kotlinx.coroutines.sync.withLock
-import kotlinx.datetime.Instant
-import space.kscience.controls.constructor.DeviceGroup
-import space.kscience.controls.manager.clock
-import space.kscience.controls.spec.DeviceBySpec
-import space.kscience.controls.spec.write
-import space.kscience.dataforge.names.parseAsName
-import kotlin.time.Duration
-import kotlin.time.Duration.Companion.milliseconds
-import kotlin.time.DurationUnit
-
-
-/**
- * Pid regulator parameters
- */
-public data class PidParameters(
-    val kp: Double,
-    val ki: Double,
-    val kd: Double,
-    val timeStep: Duration  = 1.milliseconds,
-)
-/**
- * A drive with PID regulator
- */
-public class PidRegulator(
-    public val drive: Drive,
-    public var pidParameters: PidParameters, // TODO expose as property
-) : DeviceBySpec<Regulator>(Regulator, drive.context), Regulator {
-
-    private val clock = drive.context.clock
-
-    override var target: Double = drive.position
-
-    private var lastTime: Instant = clock.now()
-    private var lastPosition: Double = target
-
-    private var integral: Double = 0.0
-
-
-    private var updateJob: Job? = null
-    private val mutex = Mutex()
-
-
-    override suspend fun onStart() {
-        drive.start()
-        updateJob = launch {
-            while (isActive) {
-                delay(pidParameters.timeStep)
-                mutex.withLock {
-                    val realTime = clock.now()
-                    val delta = target - getPosition()
-                    val dtSeconds = (realTime - lastTime).toDouble(DurationUnit.SECONDS)
-                    integral += delta * dtSeconds
-                    val derivative = (drive.position - lastPosition) / dtSeconds
-
-                    //set last time and value to new values
-                    lastTime = realTime
-                    lastPosition = drive.position
-
-                    drive.write(Drive.force,pidParameters.kp * delta + pidParameters.ki * integral + pidParameters.kd * derivative)
-                    //drive.force = pidParameters.kp * delta + pidParameters.ki * integral + pidParameters.kd * derivative
-                    propertyChanged(Regulator.position, drive.position)
-                }
-            }
-        }
-    }
-
-    override suspend fun onStop() {
-        updateJob?.cancel()
-        drive.stop()
-    }
-
-    override suspend fun getPosition(): Double = drive.position
-}
-
-public fun DeviceGroup.pid(
-    name: String,
-    drive: Drive,
-    pidParameters: PidParameters,
-): PidRegulator = install(name.parseAsName(), PidRegulator(drive, pidParameters))

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/library/Regulator.kt

@@ -1,27 +0,0 @@
-package space.kscience.controls.constructor.library
-
-import space.kscience.controls.api.Device
-import space.kscience.controls.spec.*
-import space.kscience.dataforge.meta.MetaConverter
-
-
-/**
- * A regulator with target value and current position
- */
-public interface Regulator : Device {
-    /**
-     * Get or set target value
-     */
-    public var target: Double
-
-    /**
-     * Current position value
-     */
-    public suspend fun getPosition(): Double
-
-    public companion object : DeviceSpec<Regulator>() {
-        public val target: MutableDevicePropertySpec<Regulator, Double> by mutableProperty(MetaConverter.double, Regulator::target)
-
-        public val position: DevicePropertySpec<Regulator, Double> by doubleProperty { getPosition() }
-    }
-}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/models/Inertia.kt

@@ -0,0 +1,104 @@
+package space.kscience.controls.constructor.models
+
+import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.units.*
+import space.kscience.dataforge.context.Context
+import kotlin.math.pow
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.DurationUnit
+
+/**
+ * A model for inertial movement. Both linear and angular
+ */
+public class Inertia<U : UnitsOfMeasurement, V : UnitsOfMeasurement>(
+    context: Context,
+    force: DeviceState<Double>, //TODO add system unit sets
+    inertia: Double,
+    public val position: MutableDeviceState<NumericalValue<U>>,
+    public val velocity: MutableDeviceState<NumericalValue<V>>,
+    timerPrecision: Duration = 10.milliseconds,
+) : ModelConstructor(context) {
+
+    init {
+        registerState(position)
+        registerState(velocity)
+    }
+
+    private val movementTimer = timer(timerPrecision)
+
+    private var currentForce = force.value
+
+    private val movement = movementTimer.onChange { prev, next ->
+        val dtSeconds = (next - prev).toDouble(DurationUnit.SECONDS)
+
+        // compute new value based on velocity and acceleration from the previous step
+        position.value += NumericalValue(velocity.value.value * dtSeconds + currentForce / inertia * dtSeconds.pow(2) / 2)
+
+        // compute new velocity based on acceleration on the previous step
+        velocity.value += NumericalValue(currentForce / inertia * dtSeconds)
+        currentForce = force.value
+    }
+
+    public companion object {
+        /**
+         * Linear inertial model with [force] in newtons and [mass] in kilograms
+         */
+        public fun linear(
+            context: Context,
+            force: DeviceState<NumericalValue<Newtons>>,
+            mass: NumericalValue<Kilograms>,
+            position: MutableDeviceState<NumericalValue<Meters>>,
+            velocity: MutableDeviceState<NumericalValue<MetersPerSecond>> = MutableDeviceState(NumericalValue(0.0)),
+        ): Inertia<Meters, MetersPerSecond> = Inertia(
+            context = context,
+            force = force.values(),
+            inertia = mass.value,
+            position = position,
+            velocity = velocity
+        )
+//
+//
+//        public fun linear(
+//            context: Context,
+//            force: DeviceState<NumericalValue<Newtons>>,
+//            mass: NumericalValue<Kilograms>,
+//            initialPosition: NumericalValue<Meters>,
+//            initialVelocity: NumericalValue<MetersPerSecond> = NumericalValue(0),
+//        ): Inertia<Meters, MetersPerSecond> = Inertia(
+//            context = context,
+//            force = force.values(),
+//            inertia = mass.value,
+//            position = MutableDeviceState(initialPosition),
+//            velocity = MutableDeviceState(initialVelocity)
+//        )
+
+        public fun circular(
+            context: Context,
+            force: DeviceState<NumericalValue<NewtonsMeters>>,
+            momentOfInertia: NumericalValue<KgM2>,
+            position: MutableDeviceState<NumericalValue<Degrees>>,
+            velocity: MutableDeviceState<NumericalValue<DegreesPerSecond>> = MutableDeviceState(NumericalValue(0.0)),
+        ): Inertia<Degrees, DegreesPerSecond> = Inertia(
+            context = context,
+            force = force.values(),
+            inertia = momentOfInertia.value,
+            position = position,
+            velocity = velocity
+        )
+//
+//        public fun circular(
+//            context: Context,
+//            force: DeviceState<NumericalValue<NewtonsMeters>>,
+//            momentOfInertia: NumericalValue<KgM2>,
+//            initialPosition: NumericalValue<Degrees>,
+//            initialVelocity: NumericalValue<DegreesPerSecond> = NumericalValue(0),
+//        ): Inertia<Degrees, DegreesPerSecond> = Inertia(
+//            context = context,
+//            force = force.values(),
+//            inertia = momentOfInertia.value,
+//            position = MutableDeviceState(initialPosition),
+//            velocity = MutableDeviceState(initialVelocity)
+//        )
+    }
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/models/PidRegulator.kt

@@ -0,0 +1,73 @@
+package space.kscience.controls.constructor.models
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.units.*
+import space.kscience.controls.manager.clock
+import space.kscience.dataforge.context.Context
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.DurationUnit
+
+
+/**
+ * Pid regulator parameters
+ */
+public data class PidParameters(
+    val kp: Double,
+    val ki: Double,
+    val kd: Double,
+    val timeStep: Duration = 10.milliseconds,
+)
+
+/**
+ * A PID regulator
+ *
+ * @param P units of position values
+ * @param O units of output values
+ */
+public class PidRegulator<P : UnitsOfMeasurement, O : UnitsOfMeasurement>(
+    context: Context,
+    private val position: DeviceState<NumericalValue<P>>,
+    public var pidParameters: PidParameters, // TODO expose as property
+    output: MutableDeviceState<NumericalValue<O>> = MutableDeviceState(NumericalValue(0.0)),
+    private val convertOutput: (NumericalValue<P>) -> NumericalValue<O> = { NumericalValue(it.value) },
+) : ModelConstructor(context) {
+
+    public val target: MutableDeviceState<NumericalValue<P>> = stateOf(NumericalValue(0.0))
+    public val output: MutableDeviceState<NumericalValue<O>> = registerState(output)
+
+    private val updateJob = launch {
+        var lastPosition: NumericalValue<P> = target.value
+
+        var integral: NumericalValue<P> = NumericalValue(0.0)
+
+        val mutex = Mutex()
+
+        val clock = context.clock
+
+        var lastTime = clock.now()
+
+        while (isActive) {
+            delay(pidParameters.timeStep)
+            mutex.withLock {
+                val realTime = clock.now()
+                val delta: NumericalValue<P> = target.value - position.value
+                val dtSeconds = (realTime - lastTime).toDouble(DurationUnit.SECONDS)
+                integral += delta * dtSeconds
+                val derivative = (position.value - lastPosition) / dtSeconds
+
+                //set last time and value to new values
+                lastTime = realTime
+                lastPosition = position.value
+
+                output.value =
+                    convertOutput(pidParameters.kp * delta + pidParameters.ki * integral + pidParameters.kd * derivative)
+            }
+        }
+    }
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/models/RangeState.kt

@@ -0,0 +1,68 @@
+package space.kscience.controls.constructor.models
+
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
+import space.kscience.controls.constructor.DeviceState
+import space.kscience.controls.constructor.MutableDeviceState
+import space.kscience.controls.constructor.map
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.UnitsOfMeasurement
+
+/**
+ *  A state describing a [T] value in the [range]
+ */
+public open class RangeState<T : Comparable<T>>(
+    private val input: DeviceState<T>,
+    public val range: ClosedRange<T>,
+) : DeviceState<T> {
+
+    override val valueFlow: Flow<T> get() = input.valueFlow.map { it.coerceIn(range) }
+
+    override val value: T get() = input.value.coerceIn(range)
+
+    /**
+     * A state showing that the range is on its lower boundary
+     */
+    public val atStart: DeviceState<Boolean> = input.map { it <= range.start }
+
+    /**
+     * A state showing that the range is on its higher boundary
+     */
+    public val atEnd: DeviceState<Boolean> = input.map { it >= range.endInclusive }
+
+    override fun toString(): String = "DoubleRangeState(value=${value},range=$range)"
+}
+
+public class MutableRangeState<T : Comparable<T>>(
+    private val mutableInput: MutableDeviceState<T>,
+    range: ClosedRange<T>,
+) : RangeState<T>(mutableInput, range), MutableDeviceState<T> {
+    override var value: T
+        get() = super.value
+        set(value) {
+            mutableInput.value = value.coerceIn(range)
+        }
+}
+
+public fun <T : Comparable<T>> MutableRangeState(
+    initialValue: T,
+    range: ClosedRange<T>,
+): MutableRangeState<T> = MutableRangeState<T>(MutableDeviceState(initialValue), range)
+
+public fun <U : UnitsOfMeasurement> MutableRangeState(
+    initialValue: Double,
+    range: ClosedRange<Double>,
+): MutableRangeState<NumericalValue<U>> = MutableRangeState(
+    initialValue = NumericalValue(initialValue),
+    range = NumericalValue<U>(range.start)..NumericalValue<U>(range.endInclusive)
+)
+
+
+public fun <T : Comparable<T>> DeviceState<T>.coerceIn(
+    range: ClosedFloatingPointRange<T>,
+): RangeState<T> = RangeState(this, range)
+
+
+public fun <T : Comparable<T>> MutableDeviceState<T>.coerceIn(
+    range: ClosedFloatingPointRange<T>,
+): MutableRangeState<T> = MutableRangeState(this, range)

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/models/Reducer.kt

@@ -0,0 +1,25 @@
+package space.kscience.controls.constructor.models
+
+import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.units.Degrees
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.units.times
+import space.kscience.dataforge.context.Context
+
+/**
+ * A reducer device used for simulations only (no public properties)
+ */
+public class Reducer(
+    context: Context,
+    public val ratio: Double,
+    public val input: DeviceState<NumericalValue<Degrees>>,
+    public val output: MutableDeviceState<NumericalValue<Degrees>>,
+) : ModelConstructor(context) {
+    init {
+        registerState(input)
+        registerState(output)
+        transformTo(input, output) {
+            it * ratio
+        }
+    }
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/models/ScrewDrive.kt

@@ -0,0 +1,22 @@
+package space.kscience.controls.constructor.models
+
+import space.kscience.controls.constructor.DeviceState
+import space.kscience.controls.constructor.ModelConstructor
+import space.kscience.controls.constructor.map
+import space.kscience.controls.constructor.units.Meters
+import space.kscience.controls.constructor.units.Newtons
+import space.kscience.controls.constructor.units.NewtonsMeters
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.dataforge.context.Context
+
+public class ScrewDrive(
+    context: Context,
+    public val leverage: NumericalValue<Meters>,
+) : ModelConstructor(context) {
+    public fun transformForce(
+        stateOfForce: DeviceState<NumericalValue<NewtonsMeters>>,
+    ): DeviceState<NumericalValue<Newtons>> = DeviceState.map(stateOfForce) {
+        NumericalValue(it.value * leverage.value)
+    }
+
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/units/Direction.kt

@@ -0,0 +1,6 @@
+package space.kscience.controls.constructor.units
+
+public enum class Direction(public val coef: Int) {
+    UP(1),
+    DOWN(-1)
+}

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/units/NumericalValue.kt

@@ -1,5 +1,8 @@
 package space.kscience.controls.constructor.units
 
+import space.kscience.dataforge.meta.Meta
+import space.kscience.dataforge.meta.MetaConverter
+import space.kscience.dataforge.meta.double
 import kotlin.jvm.JvmInline
 
 
@@ -7,4 +10,46 @@ import kotlin.jvm.JvmInline
  * A value without identity coupled to units of measurements.
  */
 @JvmInline
-public value class NumericalValue<T: UnitsOfMeasurement>(public val value: Double)
+public value class NumericalValue<U : UnitsOfMeasurement>(public val value: Double): Comparable<NumericalValue<U>> {
+    override fun compareTo(other: NumericalValue<U>): Int = value.compareTo(other.value)
+
+}
+
+public fun <U : UnitsOfMeasurement> NumericalValue(
+    number: Number,
+): NumericalValue<U> = NumericalValue(number.toDouble())
+
+public operator fun <U : UnitsOfMeasurement> NumericalValue<U>.plus(
+    other: NumericalValue<U>,
+): NumericalValue<U> = NumericalValue(this.value + other.value)
+
+public operator fun <U : UnitsOfMeasurement> NumericalValue<U>.minus(
+    other: NumericalValue<U>,
+): NumericalValue<U> = NumericalValue(this.value - other.value)
+
+public operator fun <U : UnitsOfMeasurement> NumericalValue<U>.times(
+    c: Number,
+): NumericalValue<U> = NumericalValue(this.value * c.toDouble())
+
+public operator fun <U : UnitsOfMeasurement> Number.times(
+    numericalValue: NumericalValue<U>,
+): NumericalValue<U> = NumericalValue(numericalValue.value * toDouble())
+
+public operator fun <U : UnitsOfMeasurement> NumericalValue<U>.times(
+    c: Double,
+): NumericalValue<U> = NumericalValue(this.value * c)
+
+public operator fun <U : UnitsOfMeasurement> NumericalValue<U>.div(
+    c: Number,
+): NumericalValue<U> = NumericalValue(this.value / c.toDouble())
+
+
+private object NumericalValueMetaConverter : MetaConverter<NumericalValue<*>> {
+    override fun convert(obj: NumericalValue<*>): Meta = Meta(obj.value)
+
+    override fun readOrNull(source: Meta): NumericalValue<*>? = source.double?.let { NumericalValue<Nothing>(it) }
+}
+
+@Suppress("UNCHECKED_CAST")
+public fun <U : UnitsOfMeasurement> MetaConverter.Companion.numerical(): MetaConverter<NumericalValue<U>> =
+    NumericalValueMetaConverter as MetaConverter<NumericalValue<U>>

controls-constructor/src/commonMain/kotlin/space/kscience/controls/constructor/units/UnitsOfMeasurement.kt

@@ -7,24 +7,54 @@ public interface UnitsOfMeasurement
 
 public interface UnitsOfLength : UnitsOfMeasurement
 
-public data object Meters: UnitsOfLength
+public data object Meters : UnitsOfLength
 
 /**/
 
-public interface UnitsOfTime: UnitsOfMeasurement
+public interface UnitsOfTime : UnitsOfMeasurement
 
-public data object Seconds: UnitsOfTime
+public data object Seconds : UnitsOfTime
 
 /**/
 
-public interface UnitsOfVelocity: UnitsOfMeasurement
+public interface UnitsOfVelocity : UnitsOfMeasurement
 
-public data object MetersPerSecond: UnitsOfVelocity
+public data object MetersPerSecond : UnitsOfVelocity
 
 /**/
 
-public interface UnitsAngularOfVelocity: UnitsOfMeasurement
+public sealed interface UnitsOfAngles : UnitsOfMeasurement
 
-public data object RadiansPerSecond: UnitsAngularOfVelocity
+public data object Radians : UnitsOfAngles
+public data object Degrees : UnitsOfAngles
 
-public data object DegreesPerSecond: UnitsAngularOfVelocity
+/**/
+
+public sealed interface UnitsAngularOfVelocity : UnitsOfMeasurement
+
+public data object RadiansPerSecond : UnitsAngularOfVelocity
+
+public data object DegreesPerSecond : UnitsAngularOfVelocity
+
+/**/
+public interface UnitsOfForce: UnitsOfMeasurement
+
+public data object Newtons: UnitsOfForce
+
+/**/
+
+public interface UnitsOfTorque: UnitsOfMeasurement
+
+public data object NewtonsMeters: UnitsOfTorque
+
+/**/
+
+public interface UnitsOfMass: UnitsOfMeasurement
+
+public data object Kilograms : UnitsOfMass
+
+/**/
+
+public interface UnitsOfMomentOfInertia: UnitsOfMeasurement
+
+public data object KgM2: UnitsOfMomentOfInertia

controls-constructor/src/commonTest/kotlin/space/kscience/controls/constructor/TimerTest.kt

@@ -15,8 +15,9 @@ class TimerTest {
     @Test
     fun timer() = runTest {
         val timer = TimerState(Global.request(ClockManager), 10.milliseconds)
-        timer.valueFlow.take(10).onEach {
+        timer.valueFlow.take(100).onEach {
             println(it)
         }.collect()
+
     }
 }

controls-core/src/commonMain/kotlin/space/kscience/controls/manager/ClockManager.kt

@@ -9,6 +9,7 @@ import space.kscience.dataforge.meta.Meta
 import space.kscience.dataforge.meta.double
 import kotlin.coroutines.CoroutineContext
 import kotlin.math.roundToLong
+import kotlin.time.Duration
 
 @OptIn(InternalCoroutinesApi::class)
 private class CompressedTimeDispatcher(
@@ -78,6 +79,14 @@ public class ClockManager : AbstractPlugin() {
         CompressedTimeDispatcher(this, dispatcher, timeCompression)
     }
 
+    public fun scheduleWithFixedDelay(tick: Duration, block: suspend () -> Unit): Job = context.launch(asDispatcher()) {
+        while (isActive) {
+            delay(tick)
+            block()
+        }
+    }
+
+
     public companion object : PluginFactory<ClockManager> {
         override val tag: PluginTag = PluginTag("clock", group = PluginTag.DATAFORGE_GROUP)
 

controls-visualisation-compose/src/commonMain/kotlin/NumberTextField.kt

@@ -0,0 +1,59 @@
+package space.kscience.controls.compose
+
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.KeyboardArrowLeft
+import androidx.compose.material.icons.filled.KeyboardArrowRight
+import androidx.compose.material3.*
+import androidx.compose.runtime.*
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Shape
+import androidx.compose.ui.text.TextStyle
+
+@Composable
+public fun NumberTextField(
+    value: Number,
+    onValueChange: (Number) -> Unit,
+    step: Double = 0.0,
+    formatter: (Number) -> String = { it.toString() },
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    textStyle: TextStyle = LocalTextStyle.current,
+    label: @Composable (() -> Unit)? = null,
+    supportingText: @Composable (() -> Unit)? = null,
+    shape: Shape = TextFieldDefaults.shape,
+    colors: TextFieldColors = TextFieldDefaults.colors(),
+) {
+    var isError by remember { mutableStateOf(false) }
+
+    Row (verticalAlignment = Alignment.CenterVertically, modifier = modifier) {
+        step.takeIf { it > 0.0 }?.let {
+            IconButton({ onValueChange(value.toDouble() - step) }, enabled = enabled) {
+                Icon(Icons.Default.KeyboardArrowLeft, "decrease value")
+            }
+        }
+        TextField(
+            value = formatter(value),
+            onValueChange = { stringValue: String ->
+                val number = stringValue.toDoubleOrNull()
+                number?.let { onValueChange(number) }
+                isError = number == null
+            },
+            isError = isError,
+            enabled = enabled,
+            textStyle = textStyle,
+            label = label,
+            supportingText = supportingText,
+            singleLine = true,
+            shape = shape,
+            colors = colors,
+            modifier = Modifier.weight(1f)
+        )
+        step.takeIf { it > 0.0 }?.let {
+            IconButton({ onValueChange(value.toDouble() + step) }, enabled = enabled) {
+                Icon(Icons.Default.KeyboardArrowRight, "increase value")
+            }
+        }
+    }
+}

controls-visualisation-compose/src/commonMain/kotlin/TimeAxisModel.kt

@@ -19,15 +19,12 @@ public class TimeAxisModel(
         val currentRange = rangeProvider()
         val rangeLength = currentRange.endInclusive - currentRange.start
         val numTicks = floor(axisLength / minimumMajorTickSpacing).toInt()
-        val numMinorTicks = numTicks * 2
         return object : TickValues<Instant> {
             override val majorTickValues: List<Instant> = List(numTicks) {
                 currentRange.start + it.toDouble() / (numTicks - 1) * rangeLength
             }
 
-            override val minorTickValues: List<Instant> = List(numMinorTicks) {
+            override val minorTickValues: List<Instant> = emptyList()
-                currentRange.start + it.toDouble() / (numMinorTicks - 1) * rangeLength
-            }
         }
     }
 

controls-visualisation-compose/src/commonMain/kotlin/koalaPlots.kt

@@ -17,6 +17,8 @@ import space.kscience.controls.api.Device
 import space.kscience.controls.api.PropertyChangedMessage
 import space.kscience.controls.api.propertyMessageFlow
 import space.kscience.controls.constructor.DeviceState
+import space.kscience.controls.constructor.units.NumericalValue
+import space.kscience.controls.constructor.values
 import space.kscience.controls.manager.clock
 import space.kscience.controls.misc.ValueWithTime
 import space.kscience.controls.spec.DevicePropertySpec
@@ -139,7 +141,7 @@ public fun XYGraphScope<Instant, Double>.PlotDeviceProperty(
 @Composable
 public fun XYGraphScope<Instant, Double>.PlotNumberState(
     context: Context,
-    state: DeviceState<out Number>,
+    state: DeviceState<Number>,
     maxAge: Duration = defaultMaxAge,
     maxPoints: Int = defaultMaxPoints,
     minPoints: Int = defaultMinPoints,
@@ -163,6 +165,19 @@ public fun XYGraphScope<Instant, Double>.PlotNumberState(
     PlotTimeSeries(points, lineStyle)
 }
 
+@Composable
+public fun XYGraphScope<Instant, Double>.PlotNumericState(
+    context: Context,
+    state: DeviceState<NumericalValue<*>>,
+    maxAge: Duration = defaultMaxAge,
+    maxPoints: Int = defaultMaxPoints,
+    minPoints: Int = defaultMinPoints,
+    sampling: Duration = defaultSampling,
+    lineStyle: LineStyle = defaultLineStyle,
+): Unit {
+    PlotNumberState(context, state.values(), maxAge, maxPoints, minPoints, sampling, lineStyle)
+}
+
 
 private fun List<Instant>.averageTime(): Instant {
     val min = min()

demo/constructor/src/jvmMain/kotlin/BodyOnSprings.kt

@@ -41,7 +41,7 @@ class Spring(
     val l0: Double,
     val begin: DeviceState<XY>,
     val end: DeviceState<XY>,
-) : ConstructorModel(context) {
+) : ModelConstructor(context) {
 
     /**
      * vector from start to end
@@ -76,7 +76,7 @@ class MaterialPoint(
     val force: DeviceState<XY>,
     val position: MutableDeviceState<XY>,
     val velocity: MutableDeviceState<XY> = MutableDeviceState(XY.ZERO),
-) : ConstructorModel(context, force, position, velocity) {
+) : ModelConstructor(context, force, position, velocity) {
 
     private val timer: TimerState = timer(2.milliseconds)
 

demo/constructor/src/jvmMain/kotlin/PidDemo.kt

@@ -23,17 +23,27 @@ import kotlinx.coroutines.flow.onEach
 import kotlinx.datetime.Instant
 import org.jetbrains.compose.splitpane.ExperimentalSplitPaneApi
 import org.jetbrains.compose.splitpane.HorizontalSplitPane
-import space.kscience.controls.compose.PlotDeviceProperty
+import space.kscience.controls.compose.NumberTextField
-import space.kscience.controls.compose.PlotNumberState
+import space.kscience.controls.compose.PlotNumericState
 import space.kscience.controls.compose.TimeAxisModel
-import space.kscience.controls.constructor.*
+import space.kscience.controls.constructor.DeviceConstructor
-import space.kscience.controls.constructor.library.*
+import space.kscience.controls.constructor.MutableDeviceState
+import space.kscience.controls.constructor.devices.Drive
+import space.kscience.controls.constructor.devices.LimitSwitch
+import space.kscience.controls.constructor.devices.LinearDrive
+import space.kscience.controls.constructor.models.Inertia
+import space.kscience.controls.constructor.models.MutableRangeState
+import space.kscience.controls.constructor.models.PidParameters
+import space.kscience.controls.constructor.models.ScrewDrive
+import space.kscience.controls.constructor.timer
+import space.kscience.controls.constructor.units.Kilograms
+import space.kscience.controls.constructor.units.Meters
+import space.kscience.controls.constructor.units.NumericalValue
 import space.kscience.controls.manager.ClockManager
 import space.kscience.controls.manager.DeviceManager
 import space.kscience.controls.manager.clock
 import space.kscience.controls.manager.install
 import space.kscience.dataforge.context.Context
-import space.kscience.dataforge.meta.Meta
 import java.awt.Dimension
 import kotlin.math.PI
 import kotlin.math.sin
@@ -43,63 +53,79 @@ import kotlin.time.Duration.Companion.seconds
 import kotlin.time.DurationUnit
 
 
-class LinearDrive(
-    drive: Drive,
-    start: LimitSwitch,
-    end: LimitSwitch,
-    pidParameters: PidParameters,
-    meta: Meta = Meta.EMPTY,
-) : DeviceConstructor(drive.context, meta) {
-
-    val drive by device(drive)
-    val pid by device(PidRegulator(drive, pidParameters))
-
-    val start by device(start)
-    val end by device(end)
-
-    val position = drive.propertyAsState(Drive.position, Double.NaN)
-
-    val target = pid.propertyAsState(Regulator.target, 0.0)
-}
-
-/**
- * A shortcut to create a virtual [LimitSwitch] from [DoubleInRangeState]
- */
-fun LinearDrive(
-    context: Context,
-    positionState: DoubleInRangeState,
-    mass: Double,
-    pidParameters: PidParameters,
-    meta: Meta = Meta.EMPTY,
-): LinearDrive = LinearDrive(
-    drive = VirtualDrive(context, mass, positionState),
-    start = VirtualLimitSwitch(context, positionState.atStart),
-    end = VirtualLimitSwitch(context, positionState.atEnd),
-    pidParameters = pidParameters,
-    meta = meta
-)
-
 class Modulator(
     context: Context,
-    target: MutableDeviceState<Double>,
+    target: MutableDeviceState<NumericalValue<Meters>>,
     var freq: Double = 0.1,
     var timeStep: Duration = 5.milliseconds,
 ) : DeviceConstructor(context) {
     private val clockStart = clock.now()
 
-    val timer = timer(10.milliseconds)
+    private val modulation = timer(10.milliseconds).onNext {
-
-    private val modulation = timer.onNext {
         val timeFromStart = clock.now() - clockStart
         val t = timeFromStart.toDouble(DurationUnit.SECONDS)
-        target.value = 5 * sin(2.0 * PI * freq * t) +
+        target.value = NumericalValue(
+            5 * sin(2.0 * PI * freq * t) +
                     sin(2 * PI * 21 * freq * t + 0.02 * (timeFromStart / timeStep))
+        )
     }
 }
 
 
+private val inertia = NumericalValue<Kilograms>(0.1)
+
+private val leverage = NumericalValue<Meters>(0.05)
+
 private val maxAge = 10.seconds
 
+private val range = -6.0..6.0
+
+/**
+ * The whole physical model is here
+ */
+private fun createLinearDriveModel(context: Context, pidParameters: PidParameters): LinearDrive {
+
+    //create a drive model with zero starting force
+    val drive = Drive(context)
+
+    //a screw drive to converse a rotational moment into a linear one
+    val screwDrive = ScrewDrive(context, leverage)
+
+    // Create a physical position coerced in a given range
+    val position = MutableRangeState<Meters>(0.0, range)
+
+    /**
+     * Create an inertia model.
+     * The inertia uses drive force as input. Position is used as both input and output
+     *
+     * Force is the input parameter, position is output parameter
+     *
+     */
+    val inertia = Inertia.linear(
+        context = context,
+        force = screwDrive.transformForce(drive.force),
+        mass = inertia,
+        position = position
+    )
+
+    /**
+     * Create a limit switches from physical position
+     */
+    val startLimitSwitch = LimitSwitch(context, position.atStart)
+    val endLimitSwitch = LimitSwitch(context, position.atEnd)
+
+    return context.install(
+        "linearDrive",
+        LinearDrive(drive, startLimitSwitch, endLimitSwitch, position, pidParameters)
+    )
+}
+
+
+private fun createModulator(linearDrive: LinearDrive): Modulator = linearDrive.context.install(
+    "modulator",
+    Modulator(linearDrive.context, linearDrive.pid.target)
+)
+
 @OptIn(ExperimentalSplitPaneApi::class, ExperimentalKoalaPlotApi::class)
 fun main() = application {
     val context = remember {
@@ -109,27 +135,16 @@ fun main() = application {
         }
     }
 
-    val clock = remember { context.clock }
-
-
     var pidParameters by remember {
-        mutableStateOf(PidParameters(kp = 2.5, ki = 0.0, kd = -0.1, timeStep = 0.005.seconds))
+        mutableStateOf(PidParameters(kp = 900.0, ki = 20.0, kd = -50.0, timeStep = 0.005.seconds))
     }
 
-    val state = remember { DoubleInRangeState(0.0, -6.0..6.0) }
+    val linearDrive: LinearDrive = remember {
-
+        createLinearDriveModel(context, pidParameters)
-    val linearDrive = remember {
-        context.install(
-            "linearDrive",
-            LinearDrive(context, state, 0.05, pidParameters)
-        )
     }
 
     val modulator = remember {
-        context.install(
+        createModulator(linearDrive)
-            "modulator",
-            Modulator(context, linearDrive.target)
-        )
     }
 
     //bind pid parameters
@@ -141,6 +156,8 @@ fun main() = application {
         }.collect()
     }
 
+    val clock = remember { context.clock }
+
     Window(title = "Pid regulator simulator", onCloseRequest = ::exitApplication) {
         window.minimumSize = Dimension(800, 400)
         MaterialTheme {
@@ -149,48 +166,51 @@ fun main() = application {
                     Column(modifier = Modifier.background(color = Color.LightGray).fillMaxHeight()) {
                         Row {
                             Text("kp:", Modifier.align(Alignment.CenterVertically).width(50.dp).padding(5.dp))
-                            TextField(
+                            NumberTextField(
-                                String.format("%.2f", pidParameters.kp),
+                                value = pidParameters.kp,
-                                { pidParameters = pidParameters.copy(kp = it.toDouble()) },
+                                onValueChange = { pidParameters = pidParameters.copy(kp = it.toDouble()) },
-                                Modifier.width(100.dp),
+                                formatter = { String.format("%.2f", it.toDouble()) },
-                                enabled = false
+                                step = 1.0,
+                                modifier = Modifier.width(200.dp),
                             )
                             Slider(
                                 pidParameters.kp.toFloat(),
                                 { pidParameters = pidParameters.copy(kp = it.toDouble()) },
-                                valueRange = 0f..20f,
+                                valueRange = 0f..1000f,
                                 steps = 100
                             )
                         }
                         Row {
                             Text("ki:", Modifier.align(Alignment.CenterVertically).width(50.dp).padding(5.dp))
-                            TextField(
+                            NumberTextField(
-                                String.format("%.2f", pidParameters.ki),
+                                value = pidParameters.ki,
-                                { pidParameters = pidParameters.copy(ki = it.toDouble()) },
+                                onValueChange = { pidParameters = pidParameters.copy(ki = it.toDouble()) },
-                                Modifier.width(100.dp),
+                                formatter = { String.format("%.2f", it.toDouble()) },
-                                enabled = false
+                                step = 0.1,
+                                modifier = Modifier.width(200.dp),
                             )
 
                             Slider(
                                 pidParameters.ki.toFloat(),
                                 { pidParameters = pidParameters.copy(ki = it.toDouble()) },
-                                valueRange = -10f..10f,
+                                valueRange = -100f..100f,
                                 steps = 100
                             )
                         }
                         Row {
                             Text("kd:", Modifier.align(Alignment.CenterVertically).width(50.dp).padding(5.dp))
-                            TextField(
+                            NumberTextField(
-                                String.format("%.2f", pidParameters.kd),
+                                value = pidParameters.kd,
-                                { pidParameters = pidParameters.copy(kd = it.toDouble()) },
+                                onValueChange = { pidParameters = pidParameters.copy(kd = it.toDouble()) },
-                                Modifier.width(100.dp),
+                                formatter = { String.format("%.2f", it.toDouble()) },
-                                enabled = false
+                                step = 0.1,
+                                modifier = Modifier.width(200.dp),
                             )
 
                             Slider(
                                 pidParameters.kd.toFloat(),
                                 { pidParameters = pidParameters.copy(kd = it.toDouble()) },
-                                valueRange = -10f..10f,
+                                valueRange = -100f..100f,
                                 steps = 100
                             )
                         }
@@ -200,14 +220,14 @@ fun main() = application {
                             TextField(
                                 pidParameters.timeStep.toString(DurationUnit.MILLISECONDS),
                                 { pidParameters = pidParameters.copy(timeStep = it.toDouble().milliseconds) },
-                                Modifier.width(100.dp),
+                                Modifier.width(200.dp),
                                 enabled = false
                             )
 
                             Slider(
                                 pidParameters.timeStep.toDouble(DurationUnit.MILLISECONDS).toFloat(),
                                 { pidParameters = pidParameters.copy(timeStep = it.toDouble().milliseconds) },
-                                valueRange = 0f..100f,
+                                valueRange = 1f..100f,
                                 steps = 100
                             )
                         }
@@ -229,7 +249,7 @@ fun main() = application {
                     ChartLayout {
                         XYGraph<Instant, Double>(
                             xAxisModel = remember { TimeAxisModel.recent(maxAge, clock) },
-                            yAxisModel = rememberDoubleLinearAxisModel(state.range),
+                            yAxisModel = rememberDoubleLinearAxisModel((range.start - 1.0)..(range.endInclusive + 1.0)),
                             xAxisTitle = { Text("Time in seconds relative to current") },
                             xAxisLabels = { it: Instant ->
                                 androidx.compose.material3.Text(
@@ -240,22 +260,16 @@ fun main() = application {
                             },
                             yAxisLabels = { it: Double -> Text(it.toString(2)) }
                         ) {
-                            PlotNumberState(
+                            PlotNumericState(
                                 context = context,
-                                state = state,
+                                state = linearDrive.position,
                                 maxAge = maxAge,
                                 sampling = 50.milliseconds,
                                 lineStyle = LineStyle(SolidColor(Color.Blue))
                             )
-                            PlotDeviceProperty(
+                            PlotNumericState(
-                                linearDrive.pid,
+                                context = context,
-                                Regulator.position,
+                                state = linearDrive.pid.target,
-                                maxAge = maxAge,
-                                sampling = 50.milliseconds,
-                            )
-                            PlotDeviceProperty(
-                                linearDrive.pid,
-                                Regulator.target,
                                 maxAge = maxAge,
                                 sampling = 50.milliseconds,
                                 lineStyle = LineStyle(SolidColor(Color.Red))
@@ -269,10 +283,6 @@ fun main() = application {
                                     }
 
                                     1 -> {
-                                        Text("Regulator position", color = Color.Black)
-                                    }
-
-                                    2 -> {
                                         Text("Regulator target", color = Color.Red)
                                     }
                                 }