Road motor vehicle comprising: - a chassis extending along a longitudinal axis between a front end and a rear end, - a shock absorber having a front face that is designed to absorb at least a portion of the energy of a mechanical impact against an obstacle received on the front face of same by deforming: • from an active position, in which same is directly exposed on the outside of the motor vehicle in front of either the front or the rear end in order to protect said end against a mechanical impact, • to a damaged position that is different from the active position, - a movement device designed to automatically move the shock absorber alternately and reversibly between: • the active position, and • a retracted position that is different from the active and damaged positions, in which this movement device comprises: • a movable stop designed to bear against a bearing face located on another vehicle before the shock absorber touches said other vehicle, this stop being reversibly movable by the reactive force of the bearing face when the vehicle approaches the other vehicle, • from a deployed position, • towards a retracted position in which the stop penetrates further towards the inside of the vehicle than in the deployed position, • a mechanical link between the stop and the shock absorber, said link being designed to transform the movement of the stop from the deployed position to the retracted position of same, into a corresponding movement of the shock absorber from the active position of same towards the retracted position of same as the stop moves towards the retracted position of same. - a chassis extending along a longitudinal axis between a front end and a rear end, - a shock absorber having a front face that is designed to absorb at least a portion of the energy of a mechanical impact against an obstacle received on the front face of same by deforming: • from an active position, in which same is directly exposed on the outside of the motor vehicle in front of either the front or the rear end in order to protect said end against a mechanical impact, • to a damaged position that is different from the active position, • from an active position, in which same is directly exposed on the outside of the motor vehicle in front of either the front or the rear end in order to protect said end against a mechanical impact, • to a damaged position that is different from the active position, - a movement device designed to automatically move the shock absorber alternately and reversibly between: • the active position, and • a retracted position that is different from the active and damaged positions, in which this movement device comprises: • a movable stop designed to bear against a bearing face located on another vehicle before the shock absorber touches said other vehicle, this stop being reversibly movable by the reactive force of the bearing face when the vehicle approaches the other vehicle, • from a deployed position, • towards a retracted position in which the stop penetrates further towards the inside of the vehicle than in the deployed position, • a mechanical link between the stop and the shock absorber, said link being designed to transform the movement of the stop from the deployed position to the retracted position of same, into a corresponding movement of the shock absorber from the active position of same towards the retracted position of same as the stop moves towards the retracted position of same. • the active position, and • a retracted position that is different from the active and damaged positions, in which this movement device comprises: • a movable stop designed to bear against a bearing face located on another vehicle before the shock absorber touches said other vehicle, this stop being reversibly movable by the reactive force of the bearing face when the vehicle approaches the other vehicle, • from a deployed position, • towards a retracted position in which the stop penetrates further towards the inside of the vehicle than in the deployed position, • from a deployed position, • towards a retracted position in which the stop penetrates further towards the inside of the vehicle than in the deployed position, • a mechanical link between the stop and the shock absorber, said link being designed to transform the movement of the stop from the deployed position to the retracted position of same, into a corresponding movement of the shock absorber from the active position of same towards the retracted position of same as the stop moves towards the retracted position of same.