Laser Tracking System for Robot Position Measurement

Today many robots are being applied in areas where accurate positioning and orientation of the robot end-effector is required. A practical approach to achieve accurate positioning of the robot end-effector is through the use of an external measuring system. In 1986, a 3-D and 6-D laser tracking interferometer systems (LTIS) were commercialized and have been used worldwide for robotic applications. However, LTIS has severe limitations such as being too expensive, lacking robustness for some industrial applications and lacking capability for measuring orientations dynamically. This proposal presents a Phase I work plan to develop an innovative, low-cost, robust, next generation laser tracking system (LTS) of robot position and orientation measurement. An innovative absolute laser ranging system based on a technique referred to as "repetitive time-of-flight" measurement will be developed. The system measures the elapsed time for a light pulse to repeatedly travel between an emitter and receiver, and converts the time to precise distance measurement. To measure angles (pitch, yaw and roll) of the robot in rel-time, an advanced optical sensor will be also developed in this program. Successful development of this next generation LTS will have significant impact in industry. In addition, it creates many opportunities for precision engineering and robotic research.