The control apparatus includes operating fluid feeding and delivery lines, a pump-brake having a containment body which defines a sliding chamber and a main piston housed sliding inside the chamber, a control element controlling the movement of the main piston which can be operated by an operator, a control device for controlling the motion transmission of a vehicle or of an operating machine including a fixed part and a moving part suitable for cooperating together, wherein the moving part is suitable for moving through the operation of the control element and includes an auxiliary piston moving between a reference position and at least a detection position and mechanically connected to the moving part to move it with respect to the fixed part during its movement between the reference position and the detection position, the auxiliary piston moving towards the detection position through the movement of the main piston.