Adding some Matlab files that deal with compliance:

• RemoteCenterOfStiffness.m: Spatial Stiffness Matrix Based on Loncaric
• Stiffness2D.m: Planar stiffness

Some other random stuff about hopping:

-- JonathanKarpick - 01 Sep 2004

• Utility of Leg Compliance
  • Running
    • SLIP
  • Climbing
    • Looking for template...
    • Attachment/Detachment requires stiffness
    • Maintaining contact requires compliance
    • Can think about it in conjunction with trajectory design (compliant mechanism kinematics)
• Tools
  • Arachi - good for forward, iterative simulations (but slow...)
  • Simplified MATLAB model - could be good for quick forward iterative simulations and possible backward analysis.
    • backward = a more analytical look at things - something akin to return maps... A good possibility is some sort of statistical analysis dealing with probabilities of attachment/adhesion, but that would come later...
    • Currently depicts ellipsoids representing compliance or stiffness at contact and resultant stiffness at CG.
    • Major question is how to determine what compliance/stiffness is required. What forces and contact characteristics are needed obviously factors in.
• Alan has a great presentation of his work on SpinyBot - thoughts on axial and normal forces required for climbing given multiple compliant hooks (toes) on a foot.
  • Role of a Stiffening Spring? Actually, role of non-linear springs in general...
    • nice = compliant for attachment, then stiff for climbing.

-- JonathanKarpick - 13 Sep 2004

• ComplianceComparisons10sep04.doc:

• EigenvaluesoftheHopper.doc: