Dubins factory functions

This commit is contained in:
Erik Schouten 2022-07-17 14:56:21 +02:00
parent 3260c3d171
commit 8faa312424
4 changed files with 175 additions and 171 deletions

View File

@ -5,8 +5,16 @@
package space.kscience.kmath.trajectory.dubins
import space.kscience.kmath.geometry.Euclidean2DSpace.distanceTo
import space.kscience.kmath.geometry.Vector2D
import space.kscience.kmath.trajectory.segments.Arc
import space.kscience.kmath.trajectory.segments.Segment
import space.kscience.kmath.trajectory.segments.Straight
import space.kscience.kmath.trajectory.segments.components.Circle
import space.kscience.kmath.trajectory.segments.components.Pose2D
import kotlin.math.acos
import kotlin.math.cos
import kotlin.math.sin
public class DubinsPath(
public val a: Arc,
@ -27,4 +35,102 @@ public class DubinsPath(
public enum class TYPE {
RLR, LRL, RSR, LSL, RSL, LSR
}
public companion object {
public fun all(start: Pose2D, end: Pose2D, turningRadius: Double): List<DubinsPath> =
listOfNotNull(
rlr(start, end, turningRadius),
lrl(start, end, turningRadius),
rsr(start, end, turningRadius),
lsl(start, end, turningRadius),
rsl(start, end, turningRadius),
lsr(start, end, turningRadius)
)
public fun shortest(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath =
all(start, end, turningRadius).minByOrNull { it.length }!!
public fun rlr(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath? {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val centers = Straight(c1.center, c2.center)
if (centers.length > turningRadius * 4) return null
var theta = theta(centers.theta - acos(centers.length / (turningRadius * 4)))
var dX = turningRadius * sin(theta)
var dY = turningRadius * cos(theta)
val p = Vector2D(c1.center.x + dX * 2, c1.center.y + dY * 2)
val e = Circle(p, turningRadius)
val p1 = Vector2D(c1.center.x + dX, c1.center.y + dY)
theta = theta(centers.theta + acos(centers.length / (turningRadius * 4)))
dX = turningRadius * sin(theta)
dY = turningRadius * cos(theta)
val p2 = Vector2D(e.center.x + dX, e.center.y + dY)
val a1 = Arc(c1.center, start, p1, Arc.Direction.RIGHT)
val a2 = Arc(e.center, p1, p2, Arc.Direction.LEFT)
val a3 = Arc(c2.center, p2, end, Arc.Direction.RIGHT)
return DubinsPath(a1, a2, a3)
}
public fun lrl(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath? {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val centers = Straight(c1.center, c2.center)
if (centers.length > turningRadius * 4) return null
var theta = theta(centers.theta + acos(centers.length / (turningRadius * 4)))
var dX = turningRadius * sin(theta)
var dY = turningRadius * cos(theta)
val p = Vector2D(c1.center.x + dX * 2, c1.center.y + dY * 2)
val e = Circle(p, turningRadius)
val p1 = Vector2D(c1.center.x + dX, c1.center.y + dY)
theta = theta(centers.theta - acos(centers.length / (turningRadius * 4)))
dX = turningRadius * sin(theta)
dY = turningRadius * cos(theta)
val p2 = Vector2D(e.center.x + dX, e.center.y + dY)
val a1 = Arc(c1.center, start, p1, Arc.Direction.LEFT)
val a2 = Arc(e.center, p1, p2, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, p2, end, Arc.Direction.LEFT)
return DubinsPath(a1, a2, a3)
}
public fun rsr(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val s = leftOuterTangent(c1, c2)
val a1 = Arc(c1.center, start, s.start, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.RIGHT)
return DubinsPath(a1, s, a3)
}
public fun lsl(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val s = rightOuterTangent(c1, c2)
val a1 = Arc(c1.center, start, s.start, Arc.Direction.LEFT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.LEFT)
return DubinsPath(a1, s, a3)
}
public fun rsl(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath? {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val s = rightInnerTangent(c1, c2)
if (c1.center.distanceTo(c2.center) < turningRadius * 2 || s == null) return null
val a1 = Arc(c1.center, start, s.start, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.LEFT)
return DubinsPath(a1, s, a3)
}
public fun lsr(start: Pose2D, end: Pose2D, turningRadius: Double): DubinsPath? {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val s = leftInnerTangent(c1, c2)
if (c1.center.distanceTo(c2.center) < turningRadius * 2 || s == null) return null
val a1 = Arc(c1.center, start, s.start, Arc.Direction.LEFT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.RIGHT)
return DubinsPath(a1, s, a3)
}
}
}

View File

@ -1,169 +0,0 @@
/*
* Copyright 2018-2021 KMath contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package space.kscience.kmath.trajectory.dubins
import space.kscience.kmath.geometry.Euclidean2DSpace.distanceTo
import space.kscience.kmath.geometry.Vector2D
import space.kscience.kmath.trajectory.segments.*
import space.kscience.kmath.trajectory.segments.components.Circle
import space.kscience.kmath.trajectory.segments.components.Pose2D
import kotlin.math.PI
import kotlin.math.acos
import kotlin.math.cos
import kotlin.math.sin
public class DubinsPathFactory(
private val start: Pose2D,
private val end: Pose2D,
private val turningRadius: Double
) {
public val all: List<DubinsPath> get() = listOfNotNull(rlr, lrl, rsr, lsl, rsl, lsr)
public val shortest: DubinsPath get() = all.minByOrNull { it.length }!!
public operator fun get(type: DubinsPath.TYPE): DubinsPath? = all.find { it.type == type }
public val rlr: DubinsPath?
get() {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val centers = Straight(c1.center, c2.center)
if (centers.length > turningRadius * 4) return null
var theta = theta(centers.theta - acos(centers.length / (turningRadius * 4)))
var dX = turningRadius * sin(theta)
var dY = turningRadius * cos(theta)
val p = Vector2D(c1.center.x + dX * 2, c1.center.y + dY * 2)
val e = Circle(p, turningRadius)
val p1 = Vector2D(c1.center.x + dX, c1.center.y + dY)
theta = theta(centers.theta + acos(centers.length / (turningRadius * 4)))
dX = turningRadius * sin(theta)
dY = turningRadius * cos(theta)
val p2 = Vector2D(e.center.x + dX, e.center.y + dY)
val a1 = Arc(c1.center, start, p1, Arc.Direction.RIGHT)
val a2 = Arc(e.center, p1, p2, Arc.Direction.LEFT)
val a3 = Arc(c2.center, p2, end, Arc.Direction.RIGHT)
return DubinsPath(a1, a2, a3)
}
private val lrl: DubinsPath?
get() {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val centers = Straight(c1.center, c2.center)
if (centers.length > turningRadius * 4) return null
var theta = theta(centers.theta + acos(centers.length / (turningRadius * 4)))
var dX = turningRadius * sin(theta)
var dY = turningRadius * cos(theta)
val p = Vector2D(c1.center.x + dX * 2, c1.center.y + dY * 2)
val e = Circle(p, turningRadius)
val p1 = Vector2D(c1.center.x + dX, c1.center.y + dY)
theta = theta(centers.theta - acos(centers.length / (turningRadius * 4)))
dX = turningRadius * sin(theta)
dY = turningRadius * cos(theta)
val p2 = Vector2D(e.center.x + dX, e.center.y + dY)
val a1 = Arc(c1.center, start, p1, Arc.Direction.LEFT)
val a2 = Arc(e.center, p1, p2, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, p2, end, Arc.Direction.LEFT)
return DubinsPath(a1, a2, a3)
}
public val rsr: DubinsPath
get() {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val s = leftOuterTangent(c1, c2)
val a1 = Arc(c1.center, start, s.start, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.RIGHT)
return DubinsPath(a1, s, a3)
}
public val lsl: DubinsPath
get() {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val s = rightOuterTangent(c1, c2)
val a1 = Arc(c1.center, start, s.start, Arc.Direction.LEFT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.LEFT)
return DubinsPath(a1, s, a3)
}
public val rsl: DubinsPath?
get() {
val c1 = start.getRightCircle(turningRadius)
val c2 = end.getLeftCircle(turningRadius)
val s = rightInnerTangent(c1, c2)
if (c1.center.distanceTo(c2.center) < turningRadius * 2 || s == null) return null
val a1 = Arc(c1.center, start, s.start, Arc.Direction.RIGHT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.LEFT)
return DubinsPath(a1, s, a3)
}
public val lsr: DubinsPath?
get() {
val c1 = start.getLeftCircle(turningRadius)
val c2 = end.getRightCircle(turningRadius)
val s = leftInnerTangent(c1, c2)
if (c1.center.distanceTo(c2.center) < turningRadius * 2 || s == null) return null
val a1 = Arc(c1.center, start, s.start, Arc.Direction.LEFT)
val a3 = Arc(c2.center, s.end, end, Arc.Direction.RIGHT)
return DubinsPath(a1, s, a3)
}
}
private enum class SIDE {
LEFT, RIGHT
}
private fun Pose2D.getLeftCircle(radius: Double): Circle = getTangentCircles(radius).first
private fun Pose2D.getRightCircle(radius: Double): Circle = getTangentCircles(radius).second
private fun Pose2D.getTangentCircles(radius: Double): Pair<Circle, Circle> {
val dX = radius * cos(theta)
val dY = radius * sin(theta)
return Circle(Vector2D(x - dX, y + dY), radius) to Circle(Vector2D(x + dX, y - dY), radius)
}
private fun leftOuterTangent(a: Circle, b: Circle) = outerTangent(a, b, SIDE.LEFT)
private fun rightOuterTangent(a: Circle, b: Circle) = outerTangent(a, b, SIDE.RIGHT)
private fun outerTangent(a: Circle, b: Circle, side: SIDE): Straight {
val centers = Straight(a.center, b.center)
val p1 = when (side) {
SIDE.LEFT -> Vector2D(
a.center.x - a.radius * cos(centers.theta),
a.center.y + a.radius * sin(centers.theta)
)
SIDE.RIGHT -> Vector2D(
a.center.x + a.radius * cos(centers.theta),
a.center.y - a.radius * sin(centers.theta)
)
}
return Straight(
p1,
Vector2D(p1.x + (centers.end.x - centers.start.x), p1.y + (centers.end.y - centers.start.y))
)
}
private fun leftInnerTangent(base: Circle, direction: Circle) = innerTangent(base, direction, SIDE.LEFT)
private fun rightInnerTangent(base: Circle, direction: Circle) = innerTangent(base, direction, SIDE.RIGHT)
private fun innerTangent(base: Circle, direction: Circle, side: SIDE): Straight? {
val centers = Straight(base.center, direction.center)
if (centers.length < base.radius * 2) return null
val angle = theta(
when (side) {
SIDE.LEFT -> centers.theta + acos(base.radius * 2 / centers.length)
SIDE.RIGHT -> centers.theta - acos(base.radius * 2 / centers.length)
}
)
val dX = base.radius * sin(angle)
val dY = base.radius * cos(angle)
val p1 = Vector2D(base.center.x + dX, base.center.y + dY)
val p2 = Vector2D(direction.center.x - dX, direction.center.y - dY)
return Straight(p1, p2)
}
internal fun theta(theta: Double) = (theta + (2 * PI)) % (2 * PI)

View File

@ -0,0 +1,67 @@
/*
* Copyright 2018-2021 KMath contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package space.kscience.kmath.trajectory.dubins
import space.kscience.kmath.geometry.Vector2D
import space.kscience.kmath.trajectory.segments.Straight
import space.kscience.kmath.trajectory.segments.components.Circle
import space.kscience.kmath.trajectory.segments.components.Pose2D
import kotlin.math.PI
import kotlin.math.acos
import kotlin.math.cos
import kotlin.math.sin
private enum class SIDE {
LEFT, RIGHT
}
internal fun Pose2D.getLeftCircle(radius: Double): Circle = getTangentCircles(radius).first
internal fun Pose2D.getRightCircle(radius: Double): Circle = getTangentCircles(radius).second
internal fun Pose2D.getTangentCircles(radius: Double): Pair<Circle, Circle> {
val dX = radius * cos(theta)
val dY = radius * sin(theta)
return Circle(Vector2D(x - dX, y + dY), radius) to Circle(Vector2D(x + dX, y - dY), radius)
}
internal fun leftOuterTangent(a: Circle, b: Circle) = outerTangent(a, b, SIDE.LEFT)
internal fun rightOuterTangent(a: Circle, b: Circle) = outerTangent(a, b, SIDE.RIGHT)
private fun outerTangent(a: Circle, b: Circle, side: SIDE): Straight {
val centers = Straight(a.center, b.center)
val p1 = when (side) {
SIDE.LEFT -> Vector2D(
a.center.x - a.radius * cos(centers.theta),
a.center.y + a.radius * sin(centers.theta)
)
SIDE.RIGHT -> Vector2D(
a.center.x + a.radius * cos(centers.theta),
a.center.y - a.radius * sin(centers.theta)
)
}
return Straight(
p1,
Vector2D(p1.x + (centers.end.x - centers.start.x), p1.y + (centers.end.y - centers.start.y))
)
}
internal fun leftInnerTangent(base: Circle, direction: Circle) = innerTangent(base, direction, SIDE.LEFT)
internal fun rightInnerTangent(base: Circle, direction: Circle) = innerTangent(base, direction, SIDE.RIGHT)
private fun innerTangent(base: Circle, direction: Circle, side: SIDE): Straight? {
val centers = Straight(base.center, direction.center)
if (centers.length < base.radius * 2) return null
val angle = theta(
when (side) {
SIDE.LEFT -> centers.theta + acos(base.radius * 2 / centers.length)
SIDE.RIGHT -> centers.theta - acos(base.radius * 2 / centers.length)
}
)
val dX = base.radius * sin(angle)
val dY = base.radius * cos(angle)
val p1 = Vector2D(base.center.x + dX, base.center.y + dY)
val p2 = Vector2D(direction.center.x - dX, direction.center.y - dY)
return Straight(p1, p2)
}
internal fun theta(theta: Double) = (theta + (2 * PI)) % (2 * PI)

View File

@ -29,7 +29,7 @@ class DubinsTests {
val start = Pose2D.of(straight.end, straight.theta)
val end = Pose2D.of(lineP1.start, lineP1.theta)
val radius = 2.0
val dubins = DubinsPathFactory(start, end, radius)
val dubins = DubinsPath.all(start, end, radius)
val absoluteDistance = start.distanceTo(end)
println("Absolute distance: $absoluteDistance")
@ -43,7 +43,7 @@ class DubinsTests {
)
expectedLengths.forEach {
val path = dubins[it.key]
val path = dubins.find { p -> p.type === it.key }
assertNotNull(path, "Path ${it.key} not found")
println("${it.key}: ${path.length}")
assertTrue(it.value.equalFloat(path.length))