Andy 3


Purpose: GLXP Mobility Milestone Prize: Winning Entry

Creator: Carnegie Mellon University

My Role: Protoflight (space-rated) mechanical design: designed suspension, motor sizing calculations



  • Four 30cm wheels
  • Differential drivetrain powered by brushless (BLDC) motors through 761:1 planetary gearboxes (direct drive)
  • 1DOF kinematic suspension

Controls: Hercules

  • Dual-core ARM processor
  • Both cores perform identical operations for error checking


  • Hall effect sensors
  • Absolute magnetic pivot encoder
  • Thermistors


Drive 500m: Large, wide wheels with 1cm grousers allow Andy to traverse the lunar terrain without fear of sinking into the soft regolith.

Climb obstacles: Direct-drive hub motors provide Andy with sufficient torque to overcome any obstacle, even during testing in Earth gravity.

Create panoramas: The two-axis pan/tilt system lets operators drive remotely, generate panorams, and inspect the rover.