Abstract: A monitoring method to detect a state of a door provided with a locking system. The method comprises the following steps: a measurement step during which a mechanical wave sensor measures a signal corresponding to a mechanical wave propagated in the door; a step of comparison between a reference signal stored in the memory and the mechanical wave signal in order to detect a state of the door. The reference signal is measured by the mechanical wave sensor while the locking system of the door is actuated.

Abstract: A monitoring method to detect a state of a door (2) provided with a locking system (2c). The method comprises the following steps: a measurement step during which a mechanical wave sensor (7) measures a signal corresponding to a mechanical wave propagated in the door (2); a step of comparison between a reference signal stored in the memory (8) and the mechanical wave signal in order to detect a state of the door (2). The reference signal is measured by the mechanical wave sensor (7) while the locking system (2c) of the door (2) is actuated.

Abstract: A device for attaching an electric battery to a chassis of a motor vehicle, and including a first quarter-turn attachment mechanism to be rigidly connected to the chassis of the motor vehicle, and a second quarter-turn attachment mechanism to be rigidly connected to the electrical battery, the first and second quarter-turn attachment mechanisms being configured to engage to attach the electric battery to the chassis of the motor vehicle.

Abstract: A method for making an axle rotating portion including a hub, at least one rolling bearing, and a stub axle, the rotating portion configured to receive a brake disc. The method includes at least one machining of the support surface of the hub, against which the disc is configured to be urged to press, the machining being carried out on a subassembly foamed by assembling at least the hub and the roller bearing and to obtain at least one part of the support surface substantially perpendicular to the axis of the roller bearing in the subassembly.

Abstract: A method for making an axle rotating portion including a hub, at least one rolling bearing, and a stub axle, the rotating portion configured to receive a brake disc. The method includes at least one machining of the support surface of the hub, against which the disc is configured to be urged to press, the machining being carried out on a subassembly formed by assembling at least the hub and the roller bearing and to obtain at least one part of the support surface substantially perpendicular to the axis of the roller bearing in the subassembly.