An ultrasonic multi-sensor system for object locating applications

The multi-sensor system is based on commercial capacitive ultra-sonic sensors integrated into the tool structure of an intelligent manipulator system. Each sensor measures the distance from the sensor head to the observed object based on the time-of-flight principle (TOF). Based on the distance measurements the position, orientation and in some cases also shape parameters of the manipulated object are estimated. Only regular shaped objects are considered, e.g. objects with cylindrical or spherical surfaces. In addition, an estimate for the resulting performance of the sensor system in the form of parameter variances/covariances is obtained. This can be utilized in designing the geometric configuration of the multi-sensor system or the sensing operations. It is shown that a poor configuration may have a drastic effect on the uncertainty.