A device for helping a wheeled vehicle, in particular for a person with impaired mobility, to pass over an obstacle, comprising: - a stationary frame comprising a bottom and two symmetrical parallel side walls (9, 10), - a plate provided with two ends, a first end being movable between a high position and a low position in which said plate constitutes an access ramp, and a second end, and - a drive assembly of said first end between a low position and a high position, said first end being supported by said drive assembly in both the low position and the high position, said drive assembly comprising: - a linear ram mounted under the plate, provided with a stationary end to said second end and rigidly connected to the bottom, and a mobile end oriented towards said first end, characterized in that the drive assembly comprises: - a carriage that is movable in horizontal translation and driven by said ram, said carriage resting on guides mounted on the bottom of the frame, said carriage comprising two pushers, - a pair of arms, the arms being symmetrical, each arm resting on one of the pushers of the carriage, each arm supporting the first end of the plate; in the retracted position of the ram actuator, the carriage being close to said second end, the arms being in the low position and the first end being in the ramp position, and in the extended position of the ram actuator the carriage being close to said first end, the arms being in the high position and the first end being in the high position. - a stationary frame comprising a bottom and two symmetrical parallel side walls (9, 10), - a plate provided with two ends, a first end being movable between a high position and a low position in which said plate constitutes an access ramp, and a second end, and - a drive assembly of said first end between a low position and a high position, said first end being supported by said drive assembly in both the low position and the high position, said drive assembly comprising: - a linear ram mounted under the plate, provided with a stationary end to said second end and rigidly connected to the bottom, and a mobile end oriented towards said first end, characterized in that the drive assembly comprises: - a carriage that is movable in horizontal translation and driven by said ram, said carriage resting on guides mounted on the bottom of the frame, said carriage comprising two pushers, - a pair of arms, the arms being symmetrical, each arm resting on one of the pushers of the carriage, each arm supporting the first end of the plate; in the retracted position of the ram actuator, the carriage being close to said second end, the arms being in the low position and the first end being in the ramp position, and in the extended position of the ram actuator the carriage being close to said first end, the arms being in the high position and the first end being in the high position. - a linear ram mounted under the plate, provided with a stationary end to said second end and rigidly connected to the bottom, and a mobile end oriented towards said first end, characterized in that the drive assembly comprises: - a carriage that is movable in horizontal translation and driven by said ram, said carriage resting on guides mounted on the bottom of the frame, said carriage comprising two pushers, - a pair of arms, the arms being symmetrical, each arm resting on one of the pushers of the carriage, each arm supporting the first end of the plate; in the retracted position of the ram actuator, the carriage being close to said second end, the arms being in the low position and the first end being in the ramp position, and in the extended position of the ram actuator the carriage being close to said first end, the arms being in the high position and the first end being in the high position. - a carriage that is movable in horizontal translation and driven by said ram, said carriage resting on guides mounted on the bottom of the frame, said carriage comprising two pushers, - a pair of arms, the arms being symmetrical, each arm resting on one of the pushers of the carriage, each arm supporting the first end of the plate; in the retracted position of the ram actuator, the carriage being close to said second end, the arms being in the low position and the first end being in the ramp position, and in the extended position of the ram actuator the carriage being close to said first end, the arms being in the high position and the first end being in the high position.