This paper describes a mechatronic (mechanical and electronic) realization of the optimal trajectory planning and guidance algorithms for minimally invasive surgical training. Specifically, the realization implements optimal navigation paths for surgical instruments in laparoscopic exercises. The underlying system platform is the Computer-Aided Surgical Trainer (CAST) that consist of mechanical fixtures equipped with encoders and servo motors. This hardware provides a means to accurately track the tip movements of laparoscopic instruments used in minimally invasive surgery. Furthermore it provides feedback to a PID controller which implements the optimal instrument trajectories. Supporting software provides all calibration procedures necessary to maintain the desired system's accuracy. Details of the mechanical, hardware, and software components are presented, along with their limitations and preliminary results.