A Laser Time-of-Flight Range Scanner for Robotic Vision

The requirements of three-dimensional scene analysis in support of vision driven robotic manipulation are such that direct range finding capabilities can greatly reduce the computational burden (time and complexity) for reliable determination of the placement and spatial extent of objects in the scene. This paper describes a laser time-of-flight range scanner capable of acquiring a reasonable rangepic of 64 × 64 spatial resolution in 4 s. However, at the current state of development, 100 samples/point are required to achieve a range accuracy of approxi-mately ±¼ cm, with a scan time of 40 s. Returned signal amplitude de-pendency is also apparent in the range determination, the dynamic range of intensity being considerable. Improved accuracy can be traded for tine. The vision/robotics laboratory environment within which the range scanner operates is briefly touched upon and some preliminary rangepic results presented.