Design and Characterization of a Six-axis Accelerometer

Abstract

External force at the end-effector is often required for the force control of robotic manipulator. In some cases, the force information measured by wrist force sensor consists of the external force and the undesired inertial force arising from the acceleration of the end-effector. Up to now, it is still difficult to extract the external force exactly for the insufficiency of acceleration information. A novel six-axis accelerometer in the type of dual annular membranes structure is presented in this paper. It can simultaneously measure all three linear acceleration components ax, ay, az and three angular acceleration components αx, αy, αz, which can be used to extract the external forces. The sensor structure and its sensing principle are described. The rated strains and interference strains obtained from Finite Element Method (FEM) simulations indicate that the accelerometer has a low level cross-sensitivity. The characteristic experiments reveal that the experimental sensitivities are in good correspondence with the results of the FEM simulations. It also shows that this accelerometer has a good linearity and minor interference errors as well as principle errors.