The trajectory is defined using the coordinate frame described on the main page of the operating guide, where the z-axis is pointed downward. Also, all units for the trajectory are expressed using inches and seconds.
The trajectory must start at the point where the moving platform comes to rest when each of the legs is held against the hardstop. This is necessary to initialize the encoders. The legs of the manipulator are driven in an open loop fashion so that they engage the hardstops and then the encoders are initialized. The most recent measurement of the hardstops shows that coordinates of the moving platform are (-0.029,0.032,8.669) when all the legs are snug against the hardstops. This should be measured again, and the initialization procedure should be recalibrated if the prototype is used for more experiments.
At this point any set of lines and arcs can be used for the trajectory. For this example, an acceleration of 40 in/sec^2, a maximum velocity of 40 in/sec, and a timestep of .05 seconds is used. The moving platform will follow a straight line path from (-0.029,0.032,8.669) to (0,0,15) in 2 seconds, and will then move along an arc with a radius of 2 inches located in the XZ plane centered about (0,0,17) in 3 seconds, and then come to a stop at (0,0,19).