Fig. 3.

Slip ratios, estimated for load forces applied in different directions, were fit with an elliptical model (A) that allowed for different axis lengths (parameters a and b) and an offset in the distal-proximal direction (parameter c). The parameter values and the goodness of fit are illustrated for four subjects inB. The left panels show the experimentally determined and predicted slip ratios as a function of load force direction. The right panels show polar plots conveying the same information.