Combined Vision/Ultrasonics For Multi-Dimensional Robotic Tracking

Abstract

An intelligent robotic system for multi-sensor based tracking and interception of moving objects which travel at unknown velocities is presented. The capability for multi-sensor assisted object tracking has been achieved through the development of techniques to track in multiple dimensions for both the static and dynamic cases. These methods are realized via the fusion of the best attributes of visual and acoustic sensing into an effective configuration that is ideal for real time tracking purposes. The kinematic information for a moving object is extracted via end effector mounted vision and ultrasonic sensors. A hybrid position/force servo-controlled gripper developed at NCSU has been used for the system implementation. One parallel actuation gripper finger houses a fiber optics based Eye-in-Hand vision sensor, while the other accommodates an ultrasonic range sensor. The primary intent of this work is to develop approaches for performing the tasks of: generalized visual/ultrasonic tracking of known rectangular entities; 3-D tracking of arbitrary pseudo-planar objects that can change orientation about the optical axis; and a real time paradigm for the tracking of motion in 3-D with variable orientation about the optical axis. This discussion includes both a description of the underlying principles and the initial experimental results.