A harmonic ring gear system can include at least one inner gear with external toothing, the at least one inner gear defining an axis of rotation; at least one outer gear with internal toothing arranged concentrically to the at least one inner gear about the axis of rotation, the internal toothing spaced apart from the external toothing; a pin ring positioned between the at least one inner gear and the at least one outer gear, the pin ring comprising a multiplicity of pins; and a rotary transmitter configured to lift a portion of the pins of the multiplicity of pins off the external toothing and press the portion of the pins into the internal toothing.

A harmonic ring gear system can include at least one inner gear with external toothing, the at least one inner gear defining an axis of rotation; at least one outer gear with internal toothing arranged concentrically to the at least one inner gear about the axis of rotation, the internal toothing spaced apart from the external toothing; a pin ring positioned between the at least one inner gear and the at least one outer gear, the pin ring comprising a multiplicity of pins; and a rotary transmitter configured to lift a portion of the pins of the multiplicity of pins off the external toothing and press the portion of the pins into the internal toothing.

A harmonic ring gear system can include at least one inner gear with external toothing, the at least one inner gear defining an axis of rotation; at least one outer gear with internal toothing arranged concentrically to the at least one inner gear about the axis of rotation, the internal toothing spaced apart from the external toothing; a pin ring positioned between the at least one inner gear and the at least one outer gear, the pin ring comprising a multiplicity of pins; and a rotary transmitter configured to lift a portion of the pins of the multiplicity of pins off the external toothing and press the portion of the pins into the internal toothing.

A harmonic ring gear system can include at least one inner gear with external toothing, the at least one inner gear defining an axis of rotation; at least one outer gear with internal toothing arranged concentrically to the at least one inner gear about the axis of rotation, the internal toothing spaced apart from the external toothing; a pin ring positioned between the at least one inner gear and the at least one outer gear, the pin ring comprising a multiplicity of pins; and a rotary transmitter configured to lift a portion of the pins of the multiplicity of pins off the external toothing and press the portion of the pins into the internal toothing.

In an aspect, a self-balancing two-wheeled vehicle is provided, having a body, and first and second wheels rotatably coupled to the body. The second wheel has at least one lateral roller rotatable about an axis that is one of oblique and orthogonal to a rotation axis of the second wheel. At least one motor is coupled to the second wheel to control rotation of the second wheel and the at least one lateral roller. At least one sensor is coupled to the body to generate orientation data therefor. A control module is coupled to the at least one motor to control operation thereof at least partially based on the orientation data generated by the at least one sensor.

In an aspect, a self-balancing two-wheeled vehicle is provided, having a body, and first and second wheels rotatably coupled to the body. The second wheel has at least one lateral roller rotatable about an axis that is one of oblique and orthogonal to a rotation axis of the second wheel. At least one motor is coupled to the second wheel to control rotation of the second wheel and the at least one lateral roller. At least one sensor is coupled to the body to generate orientation data therefor. A control module is coupled to the at least one motor to control operation thereof at least partially based on the orientation data generated by the at least one sensor.

A cardan joint steering titanium alloy hand and foot cooperatively operated bicycle capable of being ridden with one leg comprises a bicycle front wheel, a front wheel fork frame, a bicycle rear wheel, a frame body, a seat cushion assembly, a steering handlebar, paired chain wheels and a rear wheel fork frame. The upper end of a front fork rotating shaft and the lower end of an assisting stem are connected through a cardan joint component, symmetric ratchet wheels are provided on the two sides of the bicycle rear wheel, the paired chain wheels are fixed to the two sides of a frame middle shaft, pedal shaft pins are symmetrically provided on the outer sides of the paired chain wheels, and the paired chain wheels and the symmetric ratchet wheels are connected through symmetric chains.

A cardan joint steering titanium alloy hand and foot cooperatively operated bicycle capable of being ridden with one leg comprises a bicycle front wheel, a front wheel fork frame, a bicycle rear wheel, a frame body, a seat cushion assembly, a steering handlebar, paired chain wheels and a rear wheel fork frame. The upper end of a front fork rotating shaft and the lower end of an assisting stem are connected through a cardan joint component, symmetric ratchet wheels are provided on the two sides of the bicycle rear wheel, the paired chain wheels are fixed to the two sides of a frame middle shaft, pedal shaft pins are symmetrically provided on the outer sides of the paired chain wheels, and the paired chain wheels and the symmetric ratchet wheels are connected through symmetric chains.

A method for controlling engine braking in a vehicle comprises: determining a position of a throttle operator; determining a speed of the vehicle; and determining an engine braking mode selected. In response to the position of the throttle operator being a fully released position and the selected braking mode being a first engine braking mode: controlling an engine and a position of a throttle valve according to the first engine braking mode for applying a first level of engine braking. In response to the position of the throttle operator being the fully released position and the selected braking mode being the second engine braking mode: controlling the engine and the position of the throttle valve according to the second engine braking mode based at least on the speed of the vehicle for applying a second level of engine braking. A vehicle implementing the method is also disclosed.

A vehicle includes a body having a first part and a second part, which is moveably coupled to the first part. The vehicle further includes a pedal assembly having a first component coupled to the first part and a wheel assembly having a second component coupled to the second part. The vehicle further includes an extendable drive shaft having a first member and a second member. The first member is coupled to the first component and the second member is coupled to the second component. The vehicle further includes a locking mechanism having a locking member coupled to the first part and the second part of the body. The locking member, in an unlocked position, unlocks the second part from the first part to allow the second part to move over the first part, which may cause a change in a length of the extendable drive shaft.