Frameskip doesn't work as expected with Minitaur

[francis-lewis]

When adjusting frameskip for minitaur, any settings besides timestep: 0.001 and frameskip: 1 leads to erratic minitaur leg behavior when running examples/demo/controller_minitaur_nonviz.py.

[francis-lewis]

Is this potentially due to a zero order hold on robot action?

In gibson/env/env_modalities.py, we have:

def _step(self, a):
  self.nframe += 1
  if not self.scene.multiplayer:
    self.robot.apply_action(a)
    self.scene.global_step()
  rendering stuff here...

In gibson/core/physics/scene_abstract.py, we set:

p.setPhysicsEngineParameter(fixedTimeStep=self.timestep*self.frame_skip, numSolverIterations=50, numSubSteps=(self.frame_skip-1))

It seems like this will continue to command the robot action for the total time between frame renderings. Should p.stepSimulation() instead be called in a loop for frame_skip iterations to allow changing robot actions (such as from a low-level controller)?