simbody: Simbody crashing during visualization when running with a fake display server

Hi,

I keep getting this error multiple times when running in visualization mode.

Traceback (most recent call last):
  File "/home/ubuntu/SDF/osim-rl-grader/worker_dir/simulate.py", line 38, in <module>
    env = RunEnv(True)
  File "/home/ubuntu/osim-rl/osim/env/run.py", line 65, in __init__
    manager.integrate(state)
  File "/home/ubuntu/anaconda2/envs/opensim-rl/lib/python2.7/site-packages/opensim/simulation.py", line 38437, in integrate
    return _simulation.Manager_integrate(self, s, dtFirst)
RuntimeError: std::exception in 'bool OpenSim::Manager::integrate(SimTK::State &,double)': SimTK Exception thrown at VisualizerProtocol.cpp:490:
  Error detected by Simbody method VisualizerProtocol: An attempt to write() 11160 bytes to pipe 6 failed with errno=32 (Broken pipe).
  (Required condition 'status!=-1' was not met.)

terminate called after throwing an instance of 'SimTK::Exception::ErrorCheck'
  what():  SimTK Exception thrown at VisualizerProtocol.cpp:372:
  Error detected by Simbody method VisualizerProtocol: An attempt to write() 1 bytes to pipe 6 failed with errno=32 (Broken pipe).
  (Required condition 'status!=-1' was not met.)

Aborted (core dumped)

Anyone familiar with possible reasons why ? I am using a slightly modified version of simbody (https://github.com/spMohanty/simbody) to be able to force generation of frames on every render.

I run it with a xpra fake display server for programmatic generation of the frames on the server. It seems to work completely fine when I test it locally on my laptop.

will really appreciate any insights.

Thanks,