#sdfast -lc -ge -n compass.sd
#need to login to run.graphics.cs.cmu.edu
#
#              y| up
#               |
#               |______ x forward
#              /
#            z/ to side
#
# Reference configuration is as shown.  
#
#                     o  hip	
#                     ||
#                     ||
#                     ||
#                     || legs hang downwards (-y) when angle = 0;
#                        feet move forward (->, positive x) when leg angle
#                        positive     
#
# Note that since we have no body (just 2 legs), one of the legs is special
# and is "connected" to the outside world ($ground), while the other leg
# is connected to the first leg. This means that one state dimension will be an
# absolute leg angle, and another will be a relative leg angle. This asymmetry
# will be eliminated when we add a body later.
#
# This version uses SDFAST constraints to handle ground forces.

gravity = 0.0? -9.81? 0.0?

body = left_leg inb = $ground joint = planar
    mass = 37.527?                        
    inertia = 1.642 0.1 1.642?
    bodytojoint = 0 0.1? 0     
    pin = 1 0 0
    pin = 0 1 0
    pin = 0 0 1

body = right_leg inb = left_leg joint = pin
    mass = 37.527?                        
    inertia = 1.642 0.1 1.642?
    bodytojoint = 0 0.1? 0     
    inbtojoint = 0 0.1? 0
    pin = 0 0 1

constraints=5