We describe the use of well-known uncalibrated stereo algorithms for detecting planar regions in a scene from the transformation of feature locations between views. Simulations indicate that a typical set-up would have a resolution of the order of one centimetre. A fully operational system is not yet complete, but here we present a number of steps towards achieving this goal. Keywords: uncalibrated stereo vision, segmentation, planar. 1 Introduction We are developing a system which combines stereoscopic vision with a robotic manipulator to enable it to locate, reach and grasp unmodelled objects in an unstructured environment. Part of the system has been built. The algorithm for indicating the object of interest is described in [2] and the algorithm for visually guiding the robot arm to the object is described in [6]. Both these algorithms use uncalibrated stereo vision. The advantages of using uncalibrated stereo are that it is easier to set up, more robust to disturbances of t...

Autonomous vehicles could benefit greatly from visual-motion sensors of sufficiently low cost that 10 or 20 of them could be distributed around the vehicle's periphery. A design is outlined here that builds on well-known schemes using gratings. The grating principle is illustrated by the fact that a man with a torch, walking at night behind a railing, seems to flash. The frequency of flashing is proportional to his velocity. A major drawback is that backward and forward motion are not distinguished. The key development here is the use of commutation as a means of modulating the grating output signal. This is equivalent, in the illustration above, to simulating stroboscopic motion of the railing. Thus, when the man is stationary, there is flashing at a resting frequency. When he moves one way the frequency increases, and for motion the opposite way, frequency decreases. Results from an analogue implementation of the visual motion transducer are presented. The current transducer measures translational motion across the grating. The design is also shown to be capable of extension to direct measurement of the divergence and curl of the flow field.>

A design that builds on well-known schemes using gratings is outlined. The key development here is the use of commutation as a means of modulating the grating output signal. This enables backwards and forwards motion to be distinguished. Results from an analog implementation of the visual motion transducer are presented. The current transducer measures translational motion across the grating. The design is also shown to be capable of extension to direct measurement of the divergence and curl of the flow field.>