A Passive Hopper With Lossless Collisions

  • C. K. Reddy
  • R. Pratap
Conference paper
Part of the Solid Mechanics and its Applications book series (SMIA, volume 85)


A passive vertical hopping robot is here highly idealised as two vertically arranged masses acted on by gravity and coupled by a linear spring. The lower mass makes dead (e = 0) collisions with the rigid ground. The equations of motion can be reduced to a one dimensional map. Fixed points of the map are found in which case the robot hops incessantly. For these conservative solutions the lower mass collides with the ground with zero impact velocity. The interval of attraction for these conservative fixed points depends on system parameters


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Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • C. K. Reddy
    • 1
  • R. Pratap
    • 1
  1. 1.Department of Mechanical EngineeringIndian Institute of ScienceBangaloreIndia

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