Abstract: A bias offset voltage circuit for controlling one or more devices is disclosed. The bias offset voltage circuit includes a three voltage sources connected in series and a switching element. Each voltage source includes a positive terminal and a negative terminal. The switching element includes a positive input terminal, a negative input terminal, and an output terminal. The negative terminal of the first voltage source is connected to the negative input terminal. The positive terminal of the third voltage source is connected to the positive input terminal. The terminals of the second voltage source are used to drive a first device. The output terminal of the switching element drives a second device. The bias offset voltage circuit may be used to provide proper voltages to each of the devices where the higher-supplied voltage could damage the device supplied with the lower supplied voltage, or vice versa.

Abstract: Restraining device intends to protect the workman from falling while working at higher environments. The device consists of a fixed cable stretched along the area of interest. A gripping clamp which slides along the cable is attached permanently to the workman's belt. Clamp consists of a pivotal arm which, when a downward load is applied at the point of attachment of the belt, exerts a frictional force on the cable, sufficient to immediately terminate workman's fall.