Acceleration control system

• US 20110071745A1
• Filed: 10/27/2010
• Published: 03/24/2011
• 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 8,229,643 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 α_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 setting a target speed and performing acceleration control of a vehicle based on the target speed and a current speed, the acceleration control system comprising:

a surrounding body detection device 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;

means for calculating, 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

, 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 body detection device in a following Equation A;

means for storing a target acceleration calculation equation and determining a target acceleration by substituting the environmental factor determined by the calculating means, a preset target acceleration sensed value ε

₀ and a current vehicle speed for the target acceleration calculation equation,

wherein the target acceleration calculation equation is defined as a following Equation B which expresses a relation between a right side of the Equation A and a sensed value ε

of acceleration numerically expressing a driver'"'"'s acceleration feeling or an equation transformed from the Equation B, the Equation A expressing a relation between the differentiated value divided by the square power of τ and

the differentiation of the square power of the speed; and

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

2. The acceleration control system according to claim 1, wherein:

the surrounding body detection device detects the positions of a plurality of surrounding bodies present in the forward periphery of the vehicle; and

the calculating means determines the environmental factor of the Equation A based on the positions of the plurality of surrounding bodies detected by the surrounding body detection device.

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

₀.

4. The acceleration control system according to claim 3, wherein the calculating means successively determines target accelerations while maintaining constant the target acceleration sensed value ε

₀.