Sensitivity analysis and experiments of curvature estimation based on rolling contact

Curvature is a useful feature for characterizing arbitrary smooth 3-D surfaces. This paper describes our study of detecting object curvature using tactile sensing. Using the constraints on the relative motion between two bodies in contact, the curvature of an object can be obtained by inducing a relative differential motion and sensing the change in the location of contact. To understand the limitation of the practical application of this approach, sensitivity of the curvature estimate to errors in sensory data is presented. The validity of the theoretical development is examined experimentally using an optical wave-guide based tactile sensor and one finger of a three-finger dextrous hand. A good agreement between the theoretical analysis and the experimental results has been obtained.