An electrical family car, including: an electrically driven motor; and wheels with a radius larger than 90 cm. In such cars one of the dominating energy losses is directly related to the car axial to wheel friction. The car efficiency could therefore be increased by increasing the car wheel diameter which could yield a larger traveling distance for the same axial to wheel friction related energy loss.

A vehicle drive system includes a left-wheel drive unit having a first motor and a first transmission, a right-wheel drive unit having a second motor and a second transmission, and a motor control unit. Each of the first and second transmissions has a first to third rotational elements. The first motor is connected to the first rotational element of the first transmission. The second motor is connected to the first rotational element of the second transmission. The left wheel is connected to the second rotational element of the first transmission. The right wheel is connected to the second rotational element of the second transmission. The third rotational element of the first transmission and the third rotational element of the second transmission are coupled to each other. Each of the first and second transmissions has a fourth rotational element which is supported to revolve around by the second rotational element.

In a drive control device for an electric vehicle that includes brake devices (30a to 30d) provided for each of left and right wheels of the vehicle, a front motor (4) and a rear motor (6) for driving and regeneratively braking the wheels of the vehicle, a vehicle motion control unit (37) for calculating a brake application demanded amount corresponding to a yaw moment application amount to be applied to the vehicle based on the traveling state of the vehicle, a brake ECU (31) for controlling the brake devices (30a to 30d) on the left and right sides independently of each other based on the brake application demanded amount to control the yaw moment of the vehicle, and a motor torque control unit (39) for controlling driving torques and regenerative braking torques of a front motor (4) and a rear motor (6), the motor torque control unit (39) executes correction for increasing the driving torque or reducing the regenerative braking torque according to the increase of the braking torques of the brake devices (30a to 30d) based on the brake application demanded amount.

A direct current traction motor control system includes plural motors of with each of the motors configured to be coupled with a different axle of a vehicle and to rotate the axle to propel the vehicle. The motors are coupled with a DC bus and configured to receive DC via the DC bus to power the motors. The system also includes plural switch assemblies with each of the switch assemblies having an H-bridge circuit coupled with a different motor of the motors to control rotation of the motor. The system includes a controller configured to communicate control signals to the switch assemblies to individually control the H-bridge circuits to control one or more of torques output by the motors or rotation directions of the motors.

A vehicle includes a front-wheel/rear-wheel motor, a battery and an ECU. The ECU is configured to (i) control the front-wheel/rear-wheel motors, and (ii) control the front-wheel/rear-wheel motors such that a braking torque of a resonance-side motor, when at least one of the rotation speed of the front-wheel/rear-wheel motors is within a resonance range, is smaller than the braking torque of the resonance-side motor, when the rotation speed of the front-wheel/rear-wheel motors are outside the resonance range, and such that the braking torque of a non-resonance-side motor, when at least one of the rotation speed of the front-wheel/rear-wheel motors is within a resonance range, is larger than the braking torque of the non-resonance-side motor, when the rotation speed of the front-wheel/rear-wheel motors are outside the resonance range, during deceleration caused by a braking torque from the front-wheel/rear-wheel motors.

A surface treatment robot includes a chassis having forward and rear ends and a drive system carried by the chassis. The drive system includes right and left driven wheels and is configured to maneuver the robot over a cleaning surface. The robot includes a vacuum assembly, a collection volume, a supply volume, an applicator, and a wetting element, each carried by the chassis. The wetting element engages the cleaning surface to distribute a cleaning liquid applied to the surface by the applicator. The wetting element distributes the cleaning liquid along at least a portion of the cleaning surface when the robot is driven in a forward direction. The wetting element is arranged substantially forward of a transverse axis defined by the right and left driven wheels, and the wetting element slidably supports at least about ten percent of the mass of the robot above the cleaning surface.

An electric vehicle (1) includes, a chassis (10), a pair of front (21, 31) and rear wheels (22, 32) provided on a right side of the chassis (10) and a pair of front (21, 31) and rear wheels (22, 32) provided on a left side of the chassis (10), two motors (41R, 41L) that drive any of the right and left front wheels (21, 31) or the right and left rear wheels (22, 32), a sprocket (21b, 22b, 31b, 32b) and a belt (23, 33) serving as a power transmission member transmitting power between the front and rear wheels of each pair, and a battery (40) that supplies power to the electric motors (41R, 41L). Changing of a direction or turning of the electric vehicle (1) is performed by changing the rotational speed or a rotation direction by gearboxes (43R, 43L) for the power from the electric motors (41R, 41L).

An electric four-wheel drive (E-4WD) system and control method for a motor vehicle includes four wheel motors. Each wheel motor is an electric motor configured to drive one respective wheel corresponding to the wheel motor. Each wheel motor includes a stator implemented on a suspension structure of the respective wheel and a rotor implemented on a semi-axle connected to the respective wheel to rotate together with the respective wheel relative to the stator. The wheel motors are configured to drive the wheels independently of each other.

A method of stably driving an in-wheel motor vehicle having two drive motors mounted on an axle of the in-wheel motor vehicle between a left wheel and a right wheel of the in-wheel motor vehicle and configured to be drivable independently of each other for driving the left wheel and the right wheel respectively, may include detecting failure of one among the two drive motors or failure of one of two inverters electrically connected to and configured for driving the two drive motors, respectively; measuring each speed of the left wheel and the right wheel of the in-wheel motor vehicle and determining a speed difference between the speed of the left wheel and the speed of the right wheel; and controlling torque of a drive motor that operates normally among the two drive motors when the determined speed difference between the speed of the left wheel and the speed of the right wheel falls out of a preset range.

The present disclosure includes a transportation apparatus. The apparatus comprises: a surface to receive a plurality of forces at a plurality of locations thereon; a plurality of force sensors, attached to the surface, to provide information related to the plurality of forces; a plurality of wheels beneath the surface, each of the plurality of wheels being coupled with a motor; and a controller to: determine, based on the provided information, a first plurality of forces at the plurality of locations; determine, based on the first plurality of forces, a reference distribution associated with the plurality of locations; determine, based on the provided information, a second plurality of forces; determine a target speed and a target direction of the apparatus based on the reference distribution and the second plurality of forces; and provide one or more signals to the motors based on the target speed and the target direction.