Real-Time Physics Simulation Forum 2022-05-31T02:13:03+00:00 https://pybullet.org/Bullet/phpBB3/app.php/feed/topic/12974 2022-05-31T02:13:03+00:00 2022-05-31T02:13:03+00:00 https://pybullet.org/Bullet/phpBB3/viewtopic.php?p=44028#p44028 <![CDATA[Re: Applying torque control makes object fly away from the secene]]> Statistics: Posted by orange_juice — Tue May 31, 2022 2:13 am

]]> 2020-05-23T01:21:35+00:00 2020-05-23T01:21:35+00:00 https://pybullet.org/Bullet/phpBB3/viewtopic.php?p=42872#p42872 <![CDATA[Applying torque control makes object fly away from the secene]]> https://github.com/bulletphysics/pybullet_robots
I modified laikago.py example to the following, I'm only controlling one joint using torque
Strangely enough poor robot flies away from the scene!
There are two ways to fix it: either decrease simulation time step (line 10) or change torque value to 60 (line 33).
Any ideas what am I doing wrong?

Image

Code: 

import pybullet as pimport timeimport osos.chdir(os.path.dirname(os.path.abspath(__file__)))p.connect(p.GUI)plane = p.loadURDF("data/plane.urdf")p.setGravity(0,0,-9.8)timeStep = 1./300 # HERE!!! changing it to 1./400 fixes the problemp.setTimeStep(timeStep)urdfFlags = p.URDF_USE_SELF_COLLISIONquadruped = p.loadURDF("laikago/laikago_toes.urdf",[0,0,.5],[0,0.5,0.5,0], flags = urdfFlags,useFixedBase=False)#enable collision between lower legs (2,5,8 and 11)lower_legs = [2,5,8,11]for l0 in lower_legs:for l1 in lower_legs:if (l1>l0):p.setCollisionFilterPair(quadruped, quadruped, l0, l1, 1)#set dampingfor j in range (p.getNumJoints(quadruped)):p.changeDynamics(quadruped, j, linearDamping=0, angularDamping=100)p.setJointMotorControl2(quadruped, j, p.VELOCITY_CONTROL, force=0)#run the simulationp.setRealTimeSimulation(0)for i in range (1000):p.setJointMotorControl2(quadruped, 13, p.TORQUE_CONTROL, force=62) # HERE!!! changing it to force=60 fixes the problemp.stepSimulation()time.sleep(timeStep)

Statistics: Posted by m_kramar — Sat May 23, 2020 1:21 am

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