Simscape Multibody -: Model not assembled. The following violation occurred: Position Violation.

Hello,

I'm currently working on simulating a planar continuous parallel robot using Simscape, specifically the triskele bot. My goal is to modify the angles of either RevoluteJoint 0, 1 or 2 using an input. However, when I attempt this, I encounter the error mentioned below. Strangely, my model works without any errors when I provide torque input instead of motion. Could someone please help me identify where I've gone wrong? Thank you.

Project:

Is attached.

Error message:

Error:An error occurred while running the simulation and the simulation was terminated

Caused by:

['model_beam_1/Solver Configuration']: Model not assembled. The following violation occurred: Position Violation. The failure occurred during the attempt to assemble all joints in the system and satisfy any motion inputs. If an Update Diagram operation completes successfully, the failure is likely caused by motion inputs. Consider adjusting the motion inputs to specify a different starting configuration. Also consider adjusting or adding joint targets to better guide the assembly.