by Engineering




The Optical Transmitter for Pendulums (OTP) is responsible for obtaining the orthogonal coordinates of the position of the wire of a pendulum, referred to related sources. These sources are fixed to the structure whose verticality is controlled.

The TOP layout is designed so that the pendulum’s thread can be placed in a square area which is bounded by the LED arrays. This is called area of detection. The detection will occur when the thread’s shadow is detected over the illuminated area in each matrix.

The microprocessor based electronics is able to detect the shadow and calculate the centre thereof. At the end, a current signal (4-20 mA), which is proportional to the distance from the origin of the matrix, is generated.

The whole device is allocated in an opaque PVC box in order to be isolated from ambient light. Correctly attached to the structure which is wanted to be controlled, this equipment provides two signals which are directly proportional to the orthogonal coordinates of the pendulum.