ES.293 | Spring 2007 | Undergraduate

Lego Robotics


Project 1: The Claw


Project 1: The Claw, Photos
Project 2: Industrial Salvage, Photos
Project 3: Independent Robotics Projects

Each of you will build a motorized Lego “claw” that can move up and down and grasp and release objects. The tutors have already built a sample claw that can be used as a design, which we recommend if you do not have experience designing and building things with Technic Legos. However, if you wish, you may design your own claw or modify (and improve!) our design.


  • Build a copy of the Lego claw provided in lab (modifying the design if you want to)


  • Construct the claw analog position sensor (attach a position sensor to a Lego brick, attach wires and a plug to the sensor. Ask a tutor for details)
  • Construct the claw all-the-way-open limit switch (digital sensor) (ask a tutor for details)


  • Write a program (a subroutine) that moves the claw to a specified angle. For example, some subroutine ClawGoToAngle so that running ClawGoToAngle(0) moves the claw to 0 degrees (horizontal), and ClawGoToAngle(-20) moves the claw to 20 degrees below the horizontal. This subroutine should also not try to move the claw beyond its limits.
  • Write a subroutine that opens the claw. The routine should open the claw all the way and stop when it is fully open.