DEVICE HAVING ELECTROMECHANICAL TRANSDUCERS FOR DETECTING APPROACH AND/OR CONTACT IN A MOTOR VEHICLE

A device for detecting contact with and/or an approach toward a motor vehicle. The device includes a vibration generator, including a first electromechanical transducer configured to be mounted on an external element of the motor vehicle, and an electrical signal generator that delivers, to the first electromechanical transducer, an electrical signal oscillating at an excitation frequency; a rechargeable energy storage device, for supplying power to the electrical signal generator; and a vibration sensor, consisting of a second electromechanical transducer configured to be mounted on the external element of the motor vehicle. An output of the vibration sensor is connected to the rechargeable energy storage device, such that at least part of the electrical response signal recharges the rechargeable energy storage device.