A motor-driven wheel for mobile platform, said wheel comprising: - a one-piece hub comprising a first cylindrical-shaped housing defining a first internal space and a second cylindrical-shaped housing extending coaxially to the first housing and defining a second internal space communicating with the first internal space, the first housing being adapted to be attached to the frame of the mobile platform, - a drive shaft disposed coaxially with the first housing and the second housing, - a motor arrangement housed in said first internal space, comprising a brushless annular motor (210, 220, 230) connected to said drive shaft and adapted to generate a torque for rotationally driving said shaft and a braking member, said annular motor comprising a motor body, an annular-shaped stator mounted to said motor body coaxially with respect to the drive shaft and comprising a plurality of windings and a cylindrical-shaped rotor integrally and coaxially mounted to the shaft via a rotor disk movably with respect to the stator in order to rotatably drive the shaft when the windings of the stator are supplied with an electric current, said braking member of the rotor being mounted about the drive shaft coaxially with said drive shaft inside the annular motor being accommodated in the thickness of the motor arrangement, - a sensor mounted to the motor body and a magnet mounted to the end of the shaft, said sensor being configured to determine angular position of the drive shaft from said magnet in order to control the wheel, - a transmission mechanism housed in the second internal space, integrally connected to the shaft and comprising a speed reducer assembly adapted to receive the torque for rotationally driving the shaft in order to reduce its speed while increasing the torque, - a rotational guide system rotatably mounted about the second housing, - at least one rolling member comprising a rim mounted to said rotational guide system, a tire mounted to said rim in order to allow rolling of the wheel on the ground and a flange integral with both the rim and the transmission mechanism in order to transmit the increased torque received from the transmission mechanism to the rolling member, the width of the rim and the tire being less than or equal to the length of the second housing. - a one-piece hub comprising a first cylindrical-shaped housing defining a first internal space and a second cylindrical-shaped housing extending coaxially to the first housing and defining a second internal space communicating with the first internal space, the first housing being adapted to be attached to the frame of the mobile platform, - a drive shaft disposed coaxially with the first housing and the second housing, - a motor arrangement housed in said first internal space, comprising a brushless annular motor (210, 220, 230) connected to said drive shaft and adapted to generate a torque for rotationally driving said shaft and a braking member, said annular motor comprising a motor body, an annular-shaped stator mounted to said motor body coaxially with respect to the drive shaft and comprising a plurality of windings and a cylindrical-shaped rotor integrally and coaxially mounted to the shaft via a rotor disk movably with respect to the stator in order to rotatably drive the shaft when the windings of the stator are supplied with an electric current, said braking member of the rotor being mounted about the drive shaft coaxially with said drive shaft inside the annular motor being accommodated in the thickness of the motor arrangement, - a sensor mounted to the motor body and a magnet mounted to the end of the shaft, said sensor being configured to determine angular position of the drive shaft from said magnet in order to control the wheel, - a transmission mechanism housed in the second internal space, integrally connected to the shaft and comprising a speed reducer assembly adapted to receive the torque for rotationally driving the shaft in order to reduce its speed while increasing the torque, - a rotational guide system rotatably mounted about the second housing, - at least one rolling member comprising a rim mounted to said rotational guide system, a tire mounted to said rim in order to allow rolling of the wheel on the ground and a flange integral with both the rim and the transmission mechanism in order to transmit the increased torque received from the transmission mechanism to the rolling member, the width of the rim and the tire being less than or equal to the length of the second housing.