An Ultrasonic, µP-Based, Contactless Identification System for Coded Objects in Air

In this paper an identification system for m0vir.g coded objects is described. The system uses ultrasonic pulses for the recognition of a plane code suitably attached to the object. The code includes areas of different reflectivity, which are identified by the presence of echo pulses or not. Iiesides the object identification code, the system can measure with a good approximation the object velocity and acceleration urith respect to the measuring head. The measuring principle, the transducer performance, the code characteristics and dimensions will be discussed.