A continuously variable transmission on a bicycle may be automatically configured with little or no assistance from a user. Optical scanning devices, RFIDs, and other information capturing technology can communicate with a controller. The controller may then perform a portion or all of a configuration process. In operation, a controller may determine that calibration is needed. A calibration process may be initiated and performed with little or no user interaction. A calibration process may account for a load, a power source, or an environment.

Systems and methods for operating a driveline system are disclosed and include a step-variable transmission. A continuously variable transmission (CVT) is coupled between an input source and the step-variable transmission. The CVT receives a first torque from the input source and outputs a second torque. The CVT has a plurality of planetary members in rolling contact with an inner race and an outer race. A radial distance between the planetary members and a drive-transmitting member corresponds to a transmission ratio of the CVT.

A continuously variable transmission on a bicycle may be automatically configured with little or no assistance from a user. Optical scanning devices, RFIDs, and other information capturing technology can communicate with a controller. The controller may then perform a portion or all of a configuration process. In operation, a controller may determine that calibration is needed. A calibration process may be initiated and performed with little or no user interaction. A calibration process may account for a load, a power source, or an environment.

A variator for a mechanical transmission system is disclosed. Transfer means are in rolling contact with input and output members of the variator to transfer rotary motion between them. The input member is coupled to the variator input through a first biasing device arranged to exert a first biasing force on the variator according to a first, input gain which relates input torque acting on the input member and the first biasing force. The output member is coupled to the variator output through a second biasing device arranged to exert a second biasing force on the variator according to a second, output gain which relates output torque acting on the output member and the second biasing force. The first and second biasing forces clamp the variator to provide traction. The first, input gain and second, output gain are different, which, at least in specific variator applications, optimises the traction coefficient.

A fast valve actuation system for an automatic vehicle transmission includes a pair of spring-biased shift valves. Solenoids control the application of pressurized hydraulic fluid to the head of each of the shift valves. Each shift valve has at least one port that is coupled to a fluid chamber of a torque transferring mechanism of an automatic transmission. The position of each of the shift valves determines whether its ports are connected with fluid pressure. Fluid passages connect the head of each shift valve to the spring pocket of the other shift valve.

Devices and methods are provided herein for the transmission of power in motor vehicles. Power is transmitted in a smoother and more efficient manner by splitting torque into two or more torque paths. A continuously variable transmission is provided with a ball variator assembly having an array of balls, a planetary gearset coupled thereto and an arrangement of rotatable shafts with multiple gears and clutches that extend the ratio range of the variator. In some embodiments, clutches are coupled to the gear sets to enable synchronous shifting of gear modes.

Systems and methods for controlling transmissions and associated vehicles, machines, equipment, etc., are disclosed. In one case, a transmission control system includes a control unit configured to use a sensed vehicle speed and a commanded, target constant input speed to maintain an input speed substantially constant. The system includes one or more maps that associate a speed ratio of a transmission with a vehicle speed. In one embodiment, one such map associates an encoder position with a vehicle speed. Regarding a specific application, an automatic bicycle transmission shifting system is contemplated. An exemplary automatic bicycle includes a control unit, a shift actuator, various sensors, and a user interface. The control unit is configured to cooperate with a logic module and an actuator controller to control the cadence of a rider. In one embodiment, a memory of, or in communication with, the control unit includes one or more constant cadence maps that associate transmission speed ratios with bicycle speeds.

A variable speed transmission having a plurality of tilting balls and opposing input and output discs is illustrated and described that provides an infinite number of speed combinations over its transmission ratio range. The use of a planetary gear set allows minimum speeds to be in reverse and the unique geometry of the transmission allows all of the power paths to be coaxial, thereby reducing overall size and complexity of the transmission in comparison to transmissions achieving similar transmission ratio ranges.

Provided herein is a control system for a multiple-mode continuously variable transmission having a ball planetary variator. The control system has a transmission control module configured to receive a plurality of electric input signals, and to determine a mode of operation from plurality of control ranges based at least in part on the plurality of electronic input signals. The system also has an adaptive ratio control module configured to store at least one calibration map, and configured to determine an adaptive speed ratio command signal during operation of the CVP.

Provided herein is a control system for a multiple-mode continuously variable transmission having a ball planetary variator. The control system has a transmission control module configured to receive a plurality of electric input signals, and to determine a mode of operation from plurality of control ranges based at least in part on the plurality of electronic input signals. The system also has an adaptive ratio control module configured to store at least one calibration map, and configured to determine an adaptive speed ratio command signal during operation of the CVP.