I.M.P. Quadrapod


I.M.P. stands for Intelligent Mobile Platform. This was a proof of concept project intended to explore my curiosity. He is a hybrid drive quadrapod. The idea was to see how various forms of locomotion can help a robot function in a household environment.

I took this project on in my first year of engineering studies. In the end I.M.P. was able to hold 150% his own weight and perform some basic gait motions. The driving concept did not function well as the torque placed on the servos was too high and made it impossible to keep the 4 wheels aligned. An initial tail design was abandoned after these major design issues were identified.

In the end this project demonstrated that a multi-locomotion system is possible on a single chassis and can yield advantages for a robot that needs to navigate a broad range of unique terrains. Future designs need to incorporate more features in order to allow for an effective system:

  • Metal-gear Hitec servos should be used instead of cheap Chinese knockoffs which do not meet spec.
  • Springs should be utilized to reduce strain on servos when in a walking stance.
  • A hexapod design would allow for a more stable base when in walking stance.
  • Bearings should be used to allow for smooth leg operation
  • A redesign of the wheel base is necessary. The center of balance was too high and the chassis was not stable. It would be interesting to pursue designs which keep the motors on the main body as opposed to as extensions on the legs.
  • Lithium Polymer batteries must be used instead of the originally designed NiCAD batteries.
  • Motors with an integrated metal gear box would perform better than an external plastic reduction gear.

Build Pictures

Assembly_TotalFront Isometric View

Assembly_Total2Rear Isometric View

BLUEPRINT5Leg in Walking Position

BLUEPRINT6Leg in Driving Position

SDC10992Soaking Pieces to Remove Glued Templates

SDC10994Lexan Pieces After Cut, Polish and Clean

SDC11014Partial Leg Assembly

SDC11016Full Chassis Assembly and Testing Servos


SDC11018Suspended to Test Walking Gates


Weight Test 7.5 pounds

Leave a Reply

Your email address will not be published.