High-accuracy tactile pose estimation for electronic connector assembly

A pose controller for controlling a pose of an object to assemble with a mating object by a gripper of a robot arm having actuators controlled by a robot controller, the gripper including two fingers integrating tactile sensors contacting the object, comprising:

• an interface configured to receive tactile signals from the tactile sensors and transmit a control signal to the actuators;
• a processor;
• and
• a memory, in association with the processor, configured to store a precomputed set of tactile depth images and instructions of computer-implemented method, wherein each tactile depth image in the precomputed set corresponds to a simulated tactile depth image generated by a simulator by rendering a virtual depth camera view of a three-dimensional model of the object posed relative to the virtual depth camera, subtracting from each pixel of the rendered virtual depth image a distance value which is a sum of a distance between the virtual depth camera and a tactile sensor surface and penetration depth of the tactile sensors, and flooring positive pixel values to zero, and wherein the instructions of computer-implemented method cause the processor to perform steps of:
• computing measured tactile depth images from the received tactile signals;
• refining the pose of the object by matching between the precomputed set of tactile depth images and the measured tactile depth images by a point-to-plane iterative closest point (ICP) algorithm;
• generating a gripper trajectory command based on the refined pose of the object and a target pose of the object, wherein the target pose is aligned against the mating object with a nominal distance above the mating object;
• and
• controlling the actuators of the robot arm according to a gripper trajectory by transmitting the gripper trajectory command to the robot controller.