The training apparatus 1 wherein {HEAD ~ each} of said at least one transceiver is {TAIL ~ an ultrasonic transceiver} and each of said at least one reflector is an ultrasonic reflector 
The training apparatus 1 wherein { HEAD ~ each } of said at least one transceiver is { TAIL ~ an ultrasonic transceiver } and each of said at least one reflector is an ultrasonic reflector
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH