Acceleration control system

• US 20080319628A1
• Filed: 06/24/2008
• Published: 12/25/2008
• Est. Priority Date: 06/25/2007
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Fujii, Takehito, Inou, Hiroshi, Okada, Minoru, Totsuka, Seiji
• Granted Patent: US 7,853,390 B2
• Time in Patent Office: Days
• US Class Current: 701/93
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2554/4041 Position
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2720/00 Output or target parameters relating to overall vehicle dynamics
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 40/04 Traffic conditions

Abstract

An acceleration control system stores a target acceleration calculation equation acquired by transforming an equation that expresses that a product of the differentiation of the square power of the speed and the environmental factor α_env represents a sensed value ε of acceleration. A surrounding environment monitor device detects surrounding bodies present in the forward periphery of the vehicle, and an environmental factor calculation unit calculates the environmental factor α_env by using the detected positions of the surrounding bodies. A target acceleration setting unit successively sets target accelerations a_ref in compliance with the target acceleration calculation equation by using the environmental factor α_env. The acceleration is executed to match the driver'"'"'s feeling.

Claims

1. An acceleration control system for acceleration control of a vehicle in cruise control based on a target speed and a current speed, the acceleration control system comprising:

a surrounding body detection means for successively detecting positions of surrounding bodies present in a front outside periphery of the vehicle;

a target acceleration calculation means for determining a target acceleration from a relative position of the surrounding body detected by the surrounding body detection means and a sensed value ε

₀ of preset target acceleration based upon following Equations 1 to 3; and

a prime mover control means for controlling torque of a prime mover of the vehicle so as to attain the target acceleration determined by the target acceleration calculation means, wherein

5. The acceleration control system according to claim 1, wherein the target acceleration calculation means successively determines the target accelerations while maintaining constant the sensed value ε

₀ of target acceleration.

2. An acceleration control system for acceleration control of a vehicle in cruise control based on a target speed and a current speed, the acceleration control system comprising:

a surrounding body detection means for detecting positions of surrounding bodies present in a forward periphery of the vehicle on a polar coordinate system with the vehicle as a center and a line in a back-and-forth direction of the vehicle as an initial line;

an environmental factor calculation means which, when a value based on visual information on an elapse of time until the surrounding body present in front of the vehicle passes by a side of the vehicle is denoted by τ

, determines an environmental factor that is a coefficient of a differentiated term of a square power of a speed based on the position of the surrounding body detected by the surrounding environment detection means in a following Equation 4;

a target acceleration calculation means which stores a target acceleration calculation equation and determines the target acceleration by substituting the environmental factor determined by the environmental factor calculation means, a sensed value ε

₀ of a preset target acceleration and the current vehicle speed for the target acceleration calculation equation, wherein the target acceleration calculation equation is defined as a following Equation 5 which expresses a relation between the right side of the Equation 4 and the sensed value ε

of acceleration numerically expressing the driver'"'"'s acceleration feeling or an equation transformed from the Equation 5; and

a prime mover control means for controlling torque of a prime mover of the vehicle so as to attain the target acceleration, wherein

3. The acceleration control system according to claim 2, wherein the surrounding body detection means detects the positions of a plurality of surrounding bodies present in the forward periphery of the vehicle, and the environmental factor calculation means determines the environmental factor of the Equation 4 based on the positions of the plurality of surrounding bodies detected by the surrounding environment detection device.

4. The acceleration control system according to claim 2, wherein the target acceleration calculation means successively determines the target accelerations while maintaining constant the sensed value ε

₀ of target acceleration.