Control system for an infinitely variable transmission

A method for changing direction of a vehicle comprising an engine coupled to an infinitely variable transmission (IVT) having a ball-planetary variator (CVP), a direction switch, a plurality of sensors, and a computer-implemented system, the method comprising changing direction of the vehicle by:

• receiving signals from the direction switch indicating a desired vehicle direction;
• receiving signals from one or more of the sensors configured to sense a current vehicle direction, a vehicle speed, a brake pedal position, an accelerator pedal position, an engine speed, and a CVP shift position;
• detecting a power reversal condition based on the desired vehicle direction, the vehicle speed, the brake pedal position, the accelerator pedal position, the engine speed and the CVP shift position;
• commanding an engine speed limit based at least in part on the current vehicle direction, the vehicle speed, the accelerator pedal position, and the brake pedal position;
• monitoring an overspeed condition of the engine;
• and
• commanding a change in the CVP shift position based at least in part on the engine speed.

A computer-implemented system for changing direction of a vehicle having an engine coupled to an infinitely variable transmission having a ball-planetary variator (CVP), the computer-implemented system comprising:

• a digital processing device comprising an operating system configured to perform executable instructions and a memory device;
• a computer program including the instructions executable by the digital processing device, the computer program comprising a software module configured to control the change of direction of the vehicle;
• a plurality of sensors comprising:
• a vehicle direction sensor adapted to sense a vehicle direction and provide the vehicle direction to the software module,
• a vehicle speed sensor adapted to sense a vehicle speed and provide the vehicle speed to the software module,
• an engine speed sensor adapted to sense an engine speed and provide the engine speed to the software module,
• a CVP input speed sensor configured to sense a CVP input speed and provide the CVP input speed to the software module, and
• a CVP output speed sensor configured to sense a CVP output speed and provide the CVP output speed to the software module, wherein the software module determines a current CVP speed ratio based on the CVP input speed and the CVP output speed,
• wherein the software module determines a commanded CVP speed ratio during the change of the direction of the vehicle, wherein the commanded CVP speed ratio is based at least in part on the vehicle direction, the vehicle speed, the engine speed, and the current CVP speed ratio;
• wherein the software module is configured to command an engine speed limit based at least in part on the vehicle direction and the vehicle speed;
• and
• wherein the software module is configured to control the current speed ratio of CVP based on the commanded CVP speed ratio.

A computer-implemented control system for a vehicle having an engine coupled to an infinitely variable transmission having a ball-planetary variator (CVP), the computer-implemented control system comprising:

• a digital processing device comprising an operating system configured to perform executable instructions and a memory device;
• a computer program including the instructions executable by the digital processing device, the computer program comprising a software module configured to control a plurality of operating conditions of the CVP;
• a plurality of sensors comprising:
• a vehicle direction sensor configured to sense a direction of the vehicle and provide the vehicle direction to the software module,
• a vehicle speed sensor configured to sense a vehicle speed and provide the vehicle speed to the software module,,
• a brake pedal position sensor configured to sense a brake pedal position and provide the brake pedal position to the software module,
• an accelerator pedal position sensor configured to sense an accelerator pedal position and provide the accelerator pedal position to the software module,
• an engine speed sensor configured to sense an engine speed and provide the engine speed to the software module,
• a CVP input speed sensor configured to sense a CVP input speed and provide the CVP input speed to the software module, and
• a CVP output speed sensor configured to sense a CVP output speed and provide the CVP output speed to the software module, wherein the software module determines a current CVP speed ratio based on the CVP input speed
• and the CVP output speed,
• wherein the software module is configured to determine a target CVP speed ratio signal based on the accelerator pedal position, wherein the software module is configured to transmit a commanded CVP speed ratio signal based on the target CVP speed ratio signal to thereby adjust the operating condition of the CVP, wherein the software module comprises:
• a normal operation control sub-module configured to calculate the target CVP speed ratio based on the vehicle speed and the accelerator pedal position;
• an inching control sub-module configured to calculate the target CVP speed ratio based on the vehicle direction, the brake pedal position, and the engine speed;
• a power reversal control sub-module configured to calculate the target CVP speed ratio based on the current CVP speed ratio and the engine speed;
• and
• an automatic deceleration control sub-module configured to calculate the target CVP speed ratio based on the current CVP speed ratio, the vehicle speed, and the engine speed.

A computer-implemented system for changing direction of a vehicle having an engine coupled to an infinitely variable transmission having a ball-planetary variator (CVP), the computer-implemented system comprising:

• a digital processing device comprising an operating system configured to perform executable instructions and a memory device;
• a computer program including the instructions executable by the digital processing device, the computer program comprising a software module configured to control the change of direction of the vehicle;
• a plurality of sensors comprising:
• a vehicle direction sensor adapted to sense a vehicle direction and provide the vehicle direction to the software module,
• a vehicle speed sensor adapted to sense a vehicle speed and provide the vehicle speed to the software module,
• an engine speed sensor adapted to sense an engine speed and provide the engine speed to the software module,
• a CVP input speed sensor configured to sense a CVP input speed and provide the CVP input speed to the software module, and
• a CVP output speed sensor configured to sense a CVP output speed and provide the CVP output speed to the software module, wherein the software module determines a current CVP speed ratio based on the CVP input speed and the CVP output speed,
• wherein the software module determines a commanded CVP speed ratio during the change of the direction of the vehicle, wherein the commanded CVP speed ratio is based at least in part on the vehicle direction, the vehicle speed, the engine speed, and the current CVP speed ratio;
• wherein the software module is configured to command an engine speed limit based at least in part on the vehicle direction and the vehicle speed;
• and
• wherein the software module is configured to control the current speed ratio of CVP based on the commanded CVP speed ratio.