Apparatus and method for controlling motor vehicle movement

Abstract

A method for controlling a motor vehicle including the steps of transitioning the vehicle from a brake holding mode to an engine driving mode and then accelerating the vehicle in a forward direction until a set vehicle target speed has been reached. The method including maintaining the vehicle at the set target speed until a driver of the vehicle intervenes.

What is claimed is: 
     
         1 . A method of controlling a forward assist of a motor vehicle comprising:
 providing a brake system, the brake system including a brake holding mode wherein a brake of the brake system generates a brake holding force that prevents movement of a wheel of the motor vehicle;   providing an engine, the engine including an engine driving mode wherein the engine generates a driving force that rotates a wheel of the motor vehicle;   providing a human machine interface;   using said human machine interface to set a vehicle target speed;   checking whether a forward assist is requested by a driver of the vehicle;   checking whether at least one condition for the use of the forward assist is present;   determining if the vehicle is stationary;   when a forward assist is requested by a driver of the vehicle, the vehicle is stationary, and the at least one condition for the use of the automatic take-off are all present, controlling the engine of the vehicle and the braking system of the vehicle to transition the vehicle from a brake holding mode to an engine driving mode, accelerating the vehicle until the vehicle target speed is reached, and maintaining the speed of the vehicle at the vehicle target speed until there is an intervention by the driver.   
     
     
         2 . The method of  claim 1  wherein transitioning the vehicle from a brake holding mode to an engine driving mode includes increasing the driving force produced by the engine as the holding force produced by the braking system is reduced. 
     
     
         3 . The method of  claim 2  wherein the vehicle has a multi-speed transmission coupled to the engine by a torque converter and increasing the driving force produced by the engine includes increasing the rotational speed of the engine to increase the torque transmitted by the torque converter to the multi-speed transmission. 
     
     
         4 . The method of  claim 2  wherein the vehicle has a multi-speed transmission coupled to the engine by an electronically controlled friction clutch and increasing the driving force produced by the engine comprises engaging the clutch to increase the torque transmitted by the friction clutch to the multi-speed transmission. 
     
     
         5 . The method of  claim 3  wherein increasing the driving force produced by the engine further comprises increasing the torque output from the engine. 
     
     
         6 . The method of  claim 1  including the step of detecting presence of wheel slip during vehicle take-off and reducing engine driving force to reduce wheel slip. 
     
     
         7 . The method of  claim 1  including the step of detecting presence of wheel slip during vehicle take-off and applying a holding force to reduce wheel slip. 
     
     
         8 . The method of  claim 1  wherein one of the conditions for the use of the automatic take-off includes the braking system of the vehicle holding the vehicle stationary by the use of one or more electronically releasable brakes. 
     
     
         9 . The method of  claim 1  wherein a driver of the vehicle uses the human machine interface to cancel the automatic take-off. 
     
     
         10 . The method of  claim 1  wherein the automatic take-off is cancelled when a driver of the vehicle intervenes by depressing a control pedal. 
     
     
         11 . A method of controlling a forward assist of a motor vehicle comprising:
 a driver of the motor vehicle controlling a brake system to hold the motor vehicle stationary;   providing a human machine interface;   using said human machine interface to set a vehicle target speed;   checking whether a forward assist is requested by a driver of the vehicle;   checking whether at least one condition for the use of the forward assist is present;   when a forward assist is requested by a driver of the vehicle, the vehicle is stationary, the at least one condition for the use of the automatic take-off are all present, and the driver has released control of the brake system, controlling the engine of the vehicle and the braking system of the vehicle to transition the vehicle from a brake holding mode to an engine driving mode.   
     
     
         12 . The method of  claim 11  wherein the step of controlling the engine of the vehicle and the braking system of the vehicle to transition the vehicle from a brake holding mode to an engine driving mode is independent of driver action. 
     
     
         13 . The method of  claim 11  including the steps of accelerating the vehicle until the vehicle target speed is reached, and maintaining the speed of the vehicle at the vehicle target speed until there is an intervention by the driver. 
     
     
         14 . The method of  claim 11  including the step of detecting the presence of wheel slip. 
     
     
         15 . The method of  claim 14  including the step of reducing engine driving force to reduce wheel slip. 
     
     
         16 . The method of  claim 14  including the step of applying a holding force to reduce wheel slip. 
     
     
         17 . A method of controlling a forward assist of a motor vehicle comprising:
 providing a brake system, the brake system including a brake holding mode wherein a brake of the brake system generates a brake holding force that prevents movement of a wheel of the motor vehicle;   providing an engine, the engine including an engine driving mode wherein the engine generates a driving force that rotates a wheel of the motor vehicle;   when the motor vehicle is stationary, checking whether a forward assist is requested by a driver of the vehicle, using said human machine interface to set a vehicle target speed, and checking whether at least one condition for the use of the forward assist is present;   when a forward assist is requested by a driver of the vehicle, the at least one condition for the use of the automatic take-off are all present, and the driver has released control of the brake system, controlling the engine of the vehicle and the braking system of the vehicle to transition the vehicle from a brake holding mode to an engine driving mode wherein the engine and brake system control vehicle movement.   
     
     
         18 . The method of  claim 17  including adjusting control of the engine and brake system independent of driver input.