TOF Camera Array for Package Volume Measurement

Package volume is critical for logistics companies to manage transportation cost. A vision system with a 4 by 2 time of flight (TOF) camera array was proposed to measure package volume automatically. Timing control was implemented to avoid interference between different TOF sensors. A splicing algorithm was developed so that low resolution TOF sensors can be used without sacrificing measurement accuracy. The vision system is able to cover 1.6 m by 3.7 m area and to process a video stream with a frame rate greater than 22 fps. The point cloud spacing ranges between 4.1 mm and 5.8 mm. The average measurement error in volume is less than 4.7%.