There were four microphones and two Doppler radar sensors mounted on its "head", which were used to sense the sound and movement of the people around it.
A computer system (Philips P9201 - a clone of the more common Honeywell 416) controlled the robot and implemented a behavioural system so that the Senster was attracted to sound and low level movement, but repelled by loud sounds and violent movements.
The complicated acoustics of the hall and the completely unpredictable behaviour of the public made the Senster's movements seem a lot more sophisticated than the software would suggest.
After it was decommissioned, the steel structure was on display outside the firm that originally had built it on Colijnsplaat (the Netherlands).
After a lengthy restoration the Senster was reactivated as part of the 100th inauguration of the Academic Year.