Apparatus for controlling the speed of a vehicle in accordance with a predetermined schedule by manipulating the vehicle's accelerator and brake pedals. A program generator generates a reference signal that is proportional to the desired speed of the vehicle during the predetermined schedule. The reference signal is compared with a feedback signal that is proportional to the actual speed of the vehicle by a signal generating network which generates a control signal in accordance with the difference between the reference and feedback signals. An accelerator pedal control network that includes a DC motor which is driven by uniform high voltage pulses manipulates the accelerator pedal in accordance with the control signal. A brake pedal control network that includes a pneumatic actuator and an electrical to pressure transducer manipulates the brake pedal in accordance with the control signal. The operativeness of the brake pedal control network and the accelerator pedal control network and the amplification of the signal generating network are controlled by the program generator in accordance with the predetermined schedule.
A solenoid actuator connected to a servomotor for operating a control valve in response to an automatic input force overriding a manual input force when a sensed speed condition indicates a closure distance between a vehicle and an object exceeds a predetermined rate.
In an automatic gear-shifting mechanism for a shiftable transmission of motor vehicles, with two adjusting mechanisms which are each vertically pivotal about a vertical bearing and which displace a shifting lever of the gear-shifting transmission into the gear positions according to a test program, two freely movable horizontal bearings for the horizontal movement of the shifting lever are coordinated to the adjusting mechanisms and the adjusting mechanisms are constructed as electric stepping motors. The testing program is obtained with the use of the respective gear-shifting transmission.
A removable brake pedal actuator for applying a force to conventional vehicle brake pedals in accordance with a control signal for brake testing purposes is described. The actuator includes a frame which rests on the vehicle floor board and is held in place by an operator's foot. A contact pad is provided for engagement with the brake pedal. A force transferring or coupling mechanism in the form of a pneumatically operated piston cylinder assembly is connected between the frame and pedal contact pad to provide a pedal force in response to the control signal. A contact sensor is mounted on the contact pad to provide an indication that the contact pad is in actual contact with the brake pedal. A pressure sensor is also carried by the contact pad for engagement with the brake pedal to provide a signal representative of the force applied to the brake pedal. A floor clearance probe or transducer is also provided on the actuator for providing an indication that the distance between the brake pedal and vehicle floor has decreased below a minimum acceptable value. The piston can be connected to a position indicating transducer such as a potentiometer for permitting the travel of the brake pedal to be ascertained during braking tests. The actuator may be a part of a servo control loop in which feedback signals representative of a desired braking effort or brake pedal pressure are used to control the actuator.
An automatic driving system for operating a vehicle on traction rollers of a chassis dynamometer includes an accelerator pedal actuator for moving the accelerator pedal. A sensing means senses vehicle speed, accelerator pedal position and accelerator pedal actuator velocity. Accelerator pedal control means drives the accelerator pedal actuator and is coupled to the sensing means for generating a triple loop accelerator pedal control signal using vehicle speed, accelerator pedal position and actuator motor velocity feedback to reduce throttle fluctuations.
Transmission shifting method with clutch pedal and accelerator pedal control for the automatic operation of manual shifting mechanisms in an automotive vehicle include gear shifting, open loop accelerator pedal control during shifting, acceleration from idle with slow clutch release, deceleration to idle, control of coasting, and determining clutch engagement point and shifter positions at various gear shift points.
