Estimation of Lightweight Object's Mass by a Humanoid Robot During a Precision Grip with Soft Tactile Sensors

Abstract

The estimation of the intrinsic properties of an unknown object is a very challenging problem, mainly due the limitations on the tactile technology. In this article we present a method to estimate an object's weight during a precision grip made by a humanoid robot. Tactile sensors on the fingertips provide information on the 3D force vector during a movement of grasping and lifting a cup filled with different masses (30-100g). Using the force measurements across time, we were able to successfully calculate the object weight for 8 different masses, with repeatable measurement and low deviations from the real value, especially for higher object masses.