Files
bullet3/examples/pybullet/examples/pdControllerStable.py
Erwin Coumans ef9570c315 add yapf style and apply yapf to format all Python files
This recreates pull request #2192
2019-04-27 07:31:15 -07:00

149 lines
4.4 KiB
Python

import numpy as np
class PDControllerStableMultiDof(object):
def __init__(self, pb):
self._pb = pb
def computePD(self, bodyUniqueId, jointIndices, desiredPositions, desiredVelocities, kps, kds,
maxForces, timeStep):
numJoints = len(jointIndices) #self._pb.getNumJoints(bodyUniqueId)
curPos, curOrn = self._pb.getBasePositionAndOrientation(bodyUniqueId)
#q1 = [desiredPositions[0],desiredPositions[1],desiredPositions[2],desiredPositions[3],desiredPositions[4],desiredPositions[5],desiredPositions[6]]
q1 = [curPos[0], curPos[1], curPos[2], curOrn[0], curOrn[1], curOrn[2], curOrn[3]]
#qdot1 = [0,0,0, 0,0,0,0]
baseLinVel, baseAngVel = self._pb.getBaseVelocity(bodyUniqueId)
qdot1 = [
baseLinVel[0], baseLinVel[1], baseLinVel[2], baseAngVel[0], baseAngVel[1], baseAngVel[2], 0
]
qError = [0, 0, 0, 0, 0, 0, 0]
qIndex = 7
qdotIndex = 7
zeroAccelerations = [0, 0, 0, 0, 0, 0, 0]
for i in range(numJoints):
js = self._pb.getJointStateMultiDof(bodyUniqueId, jointIndices[i])
jointPos = js[0]
jointVel = js[1]
q1 += jointPos
if len(js[0]) == 1:
desiredPos = desiredPositions[qIndex]
qdiff = desiredPos - jointPos[0]
qError.append(qdiff)
zeroAccelerations.append(0.)
qdot1 += jointVel
qIndex += 1
qdotIndex += 1
if len(js[0]) == 4:
desiredPos = [
desiredPositions[qIndex], desiredPositions[qIndex + 1], desiredPositions[qIndex + 2],
desiredPositions[qIndex + 3]
]
axis = self._pb.getAxisDifferenceQuaternion(desiredPos, jointPos)
jointVelNew = [jointVel[0], jointVel[1], jointVel[2], 0]
qdot1 += jointVelNew
qError.append(axis[0])
qError.append(axis[1])
qError.append(axis[2])
qError.append(0)
desiredVel = [
desiredVelocities[qdotIndex], desiredVelocities[qdotIndex + 1],
desiredVelocities[qdotIndex + 2]
]
zeroAccelerations += [0., 0., 0., 0.]
qIndex += 4
qdotIndex += 4
q = np.array(q1)
qdot = np.array(qdot1)
qdotdesired = np.array(desiredVelocities)
qdoterr = qdotdesired - qdot
Kp = np.diagflat(kps)
Kd = np.diagflat(kds)
p = Kp.dot(qError)
#np.savetxt("pb_qError.csv", qError, delimiter=",")
#np.savetxt("pb_p.csv", p, delimiter=",")
d = Kd.dot(qdoterr)
#np.savetxt("pb_d.csv", d, delimiter=",")
#np.savetxt("pbqdoterr.csv", qdoterr, delimiter=",")
M1 = self._pb.calculateMassMatrix(bodyUniqueId, q1, flags=1)
M2 = np.array(M1)
#np.savetxt("M2.csv", M2, delimiter=",")
M = (M2 + Kd * timeStep)
#np.savetxt("pbM_tKd.csv",M, delimiter=",")
c1 = self._pb.calculateInverseDynamics(bodyUniqueId, q1, qdot1, zeroAccelerations, flags=1)
c = np.array(c1)
#np.savetxt("pbC.csv",c, delimiter=",")
A = M
#p = [0]*43
b = p + d - c
#np.savetxt("pb_acc.csv",b, delimiter=",")
qddot = np.linalg.solve(A, b)
tau = p + d - Kd.dot(qddot) * timeStep
#print("len(tau)=",len(tau))
maxF = np.array(maxForces)
forces = np.clip(tau, -maxF, maxF)
return forces
class PDControllerStable(object):
def __init__(self, pb):
self._pb = pb
def computePD(self, bodyUniqueId, jointIndices, desiredPositions, desiredVelocities, kps, kds,
maxForces, timeStep):
numJoints = self._pb.getNumJoints(bodyUniqueId)
jointStates = self._pb.getJointStates(bodyUniqueId, jointIndices)
q1 = []
qdot1 = []
zeroAccelerations = []
for i in range(numJoints):
q1.append(jointStates[i][0])
qdot1.append(jointStates[i][1])
zeroAccelerations.append(0)
q = np.array(q1)
qdot = np.array(qdot1)
qdes = np.array(desiredPositions)
qdotdes = np.array(desiredVelocities)
qError = qdes - q
qdotError = qdotdes - qdot
Kp = np.diagflat(kps)
Kd = np.diagflat(kds)
p = Kp.dot(qError)
d = Kd.dot(qdotError)
forces = p + d
M1 = self._pb.calculateMassMatrix(bodyUniqueId, q1)
M2 = np.array(M1)
M = (M2 + Kd * timeStep)
c1 = self._pb.calculateInverseDynamics(bodyUniqueId, q1, qdot1, zeroAccelerations)
c = np.array(c1)
A = M
b = -c + p + d
qddot = np.linalg.solve(A, b)
tau = p + d - Kd.dot(qddot) * timeStep
maxF = np.array(maxForces)
forces = np.clip(tau, -maxF, maxF)
#print("c=",c)
return tau