chapter
Visual Control of Braking from 2nd-Order Relative Optical Expansion
Pages 4

Lee (1976) showed that during a constant velocity approach, the time-tocontact with an object is specified by the inverse of its relative rate of optical expansion (t). Lee further proposed that the time derivative of t ct, or "tau-dot") could be used to control deceleration during braking. The experiment described here tests Lee's hypothesis, using an active closed-loop task. First we will describe the t strategy and some alternatives, and then we will describe the test.