bullet3/examples/pybullet/gym/pybullet_envs/bullet/kuka.py

import os,  inspect
currentdir = os.path.dirname(os.path.abspath(inspect.getfile(inspect.currentframe())))
parentdir = os.path.dirname(os.path.dirname(currentdir))
os.sys.path.insert(0,parentdir)

import pybullet as p
import numpy as np
import copy
import math
import pybullet_data


class Kuka:

  def __init__(self, urdfRootPath=pybullet_data.getDataPath(), timeStep=0.01):
    self.urdfRootPath = urdfRootPath
    self.timeStep = timeStep
    self.maxVelocity = .35
    self.maxForce = 200.
    self.fingerAForce = 2 
    self.fingerBForce = 2.5
    self.fingerTipForce = 2
    self.useInverseKinematics = 1
    self.useSimulation = 1
    self.useNullSpace =21
    self.useOrientation = 1
    self.kukaEndEffectorIndex = 6
    self.kukaGripperIndex = 7
    #lower limits for null space
    self.ll=[-.967,-2 ,-2.96,0.19,-2.96,-2.09,-3.05]
    #upper limits for null space
    self.ul=[.967,2 ,2.96,2.29,2.96,2.09,3.05]
    #joint ranges for null space
    self.jr=[5.8,4,5.8,4,5.8,4,6]
    #restposes for null space
    self.rp=[0,0,0,0.5*math.pi,0,-math.pi*0.5*0.66,0]
    #joint damping coefficents
    self.jd=[0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001,0.00001]
    self.reset()
    
  def reset(self):
    objects = p.loadSDF(os.path.join(self.urdfRootPath,"kuka_iiwa/kuka_with_gripper2.sdf"))
    self.kukaUid = objects[0]
    #for i in range (p.getNumJoints(self.kukaUid)):
    #  print(p.getJointInfo(self.kukaUid,i))
    p.resetBasePositionAndOrientation(self.kukaUid,[-0.100000,0.000000,0.070000],[0.000000,0.000000,0.000000,1.000000])
    self.jointPositions=[ 0.006418, 0.413184, -0.011401, -1.589317, 0.005379, 1.137684, -0.006539, 0.000048, -0.299912, 0.000000, -0.000043, 0.299960, 0.000000, -0.000200 ]
    self.numJoints = p.getNumJoints(self.kukaUid)
    for jointIndex in range (self.numJoints):
      p.resetJointState(self.kukaUid,jointIndex,self.jointPositions[jointIndex])
      p.setJointMotorControl2(self.kukaUid,jointIndex,p.POSITION_CONTROL,targetPosition=self.jointPositions[jointIndex],force=self.maxForce)
    
    self.trayUid = p.loadURDF(os.path.join(self.urdfRootPath,"tray/tray.urdf"), 0.640000,0.075000,-0.190000,0.000000,0.000000,1.000000,0.000000)
    self.endEffectorPos = [0.537,0.0,0.5]
    self.endEffectorAngle = 0
    
    
    self.motorNames = []
    self.motorIndices = []
    
    for i in range (self.numJoints):
      jointInfo = p.getJointInfo(self.kukaUid,i)
      qIndex = jointInfo[3]
      if qIndex > -1:
        #print("motorname")
        #print(jointInfo[1])
        self.motorNames.append(str(jointInfo[1]))
        self.motorIndices.append(i)

  def getActionDimension(self):
    if (self.useInverseKinematics):
      return len(self.motorIndices)
    return 6 #position x,y,z and roll/pitch/yaw euler angles of end effector

  def getObservationDimension(self):
    return len(self.getObservation())

  def getObservation(self):
    observation = []
    state = p.getLinkState(self.kukaUid,self.kukaGripperIndex)
    pos = state[0]
    orn = state[1]
    euler = p.getEulerFromQuaternion(orn)
        
    observation.extend(list(pos))
    observation.extend(list(euler))
    
    return observation

  def applyAction(self, motorCommands):
    
    #print ("self.numJoints")
    #print (self.numJoints)
    if (self.useInverseKinematics):
      
      dx = motorCommands[0]
      dy = motorCommands[1]
      dz = motorCommands[2]
      da = motorCommands[3]
      fingerAngle = motorCommands[4]
      
      state = p.getLinkState(self.kukaUid,self.kukaEndEffectorIndex)
      actualEndEffectorPos = state[0]
      #print("pos[2] (getLinkState(kukaEndEffectorIndex)")
      #print(actualEndEffectorPos[2])
      
    
      
      self.endEffectorPos[0] = self.endEffectorPos[0]+dx
      if (self.endEffectorPos[0]>0.65):
        self.endEffectorPos[0]=0.65
      if (self.endEffectorPos[0]<0.50):
        self.endEffectorPos[0]=0.50
      self.endEffectorPos[1] = self.endEffectorPos[1]+dy
      if (self.endEffectorPos[1]<-0.17):
        self.endEffectorPos[1]=-0.17
      if (self.endEffectorPos[1]>0.22):
        self.endEffectorPos[1]=0.22
      
      #print ("self.endEffectorPos[2]")
      #print (self.endEffectorPos[2])
      #print("actualEndEffectorPos[2]")
      #print(actualEndEffectorPos[2])
      #if (dz<0 or actualEndEffectorPos[2]<0.5):
      self.endEffectorPos[2] = self.endEffectorPos[2]+dz
    
     
      self.endEffectorAngle = self.endEffectorAngle + da
      pos = self.endEffectorPos
      orn = p.getQuaternionFromEuler([0,-math.pi,0]) # -math.pi,yaw])
      if (self.useNullSpace==1):
        if (self.useOrientation==1):
          jointPoses = p.calculateInverseKinematics(self.kukaUid,self.kukaEndEffectorIndex,pos,orn,self.ll,self.ul,self.jr,self.rp)
        else:
          jointPoses = p.calculateInverseKinematics(self.kukaUid,self.kukaEndEffectorIndex,pos,lowerLimits=self.ll, upperLimits=self.ul, jointRanges=self.jr, restPoses=self.rp)
      else:
        if (self.useOrientation==1):
          jointPoses = p.calculateInverseKinematics(self.kukaUid,self.kukaEndEffectorIndex,pos,orn,jointDamping=self.jd)
        else:
          jointPoses = p.calculateInverseKinematics(self.kukaUid,self.kukaEndEffectorIndex,pos)
    
      #print("jointPoses")
      #print(jointPoses)
      #print("self.kukaEndEffectorIndex")
      #print(self.kukaEndEffectorIndex)
      if (self.useSimulation):
        for i in range (self.kukaEndEffectorIndex+1):
          #print(i)
          p.setJointMotorControl2(bodyUniqueId=self.kukaUid,jointIndex=i,controlMode=p.POSITION_CONTROL,targetPosition=jointPoses[i],targetVelocity=0,force=self.maxForce,maxVelocity=self.maxVelocity, positionGain=0.3,velocityGain=1)
      else:
        #reset the joint state (ignoring all dynamics, not recommended to use during simulation)
        for i in range (self.numJoints):
          p.resetJointState(self.kukaUid,i,jointPoses[i])
      #fingers
      p.setJointMotorControl2(self.kukaUid,7,p.POSITION_CONTROL,targetPosition=self.endEffectorAngle,force=self.maxForce)
      p.setJointMotorControl2(self.kukaUid,8,p.POSITION_CONTROL,targetPosition=-fingerAngle,force=self.fingerAForce)
      p.setJointMotorControl2(self.kukaUid,11,p.POSITION_CONTROL,targetPosition=fingerAngle,force=self.fingerBForce)
      
      p.setJointMotorControl2(self.kukaUid,10,p.POSITION_CONTROL,targetPosition=0,force=self.fingerTipForce)
      p.setJointMotorControl2(self.kukaUid,13,p.POSITION_CONTROL,targetPosition=0,force=self.fingerTipForce)
      
      
    else:
      for action in range (len(motorCommands)):
        motor = self.motorIndices[action]
        p.setJointMotorControl2(self.kukaUid,motor,p.POSITION_CONTROL,targetPosition=motorCommands[action],force=self.maxForce)