Method and device for assisting a driver of a vehicle

• US 6,549,841 B1
• Filed: 07/10/2002
• Issued: 04/15/2003
• Est. Priority Date: 08/27/1999
• Status: Expired due to Fees

• Current Assignee: Thoreb AB
• Original Assignee: Thoreb AB
• Inventors: AxElsson, Roger
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US10/069,549
• Time in Patent Office: 279 Days
• Field of Search: 701/66, 701/70, 701/78, 701/79, 701/82, 701/84, 701/101, 701/110, 701/121, 731/172
• US Class Current: 701/70
• CPC Class Codes: B60K 26/021 with means for providing feel, e.g. by changing pedal force characteristics
• CPC Class Codes: B60K 31/0058 responsive to externally generated signalling
• CPC Class Codes: B60T 2210/24 Curve radius
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/30 Road curve radius
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2720/103 Speed profile
• CPC Class Codes: B60Y 2200/143 Busses
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

The invention relates to a method and a device for assisting a driver of a vehicle, said vehicle having an engine and a braking system, an accelerator that conveys the driver'"'"'s wishes concerning acceleration to the engine, and a brake pedal that conveys the driver'"'"'s wishes concerneing retardation to the braking system. In accordance with the method a speed profile is determined for the driving distance, which speed profile comprises a relation between a speed set point and position. Furthermore, the engine and the braking system are controlled on the basis of the speed profile and at least one actuator influences the accelerator or braking pedal of the vehicle in accordance with said control. The driver is permitted to override the influence of the actuator only if a force that is greater than a predetermined threshold value is applied on one of the pedals.

Claims

1. A method for assisting a driver (4) of a vehicle (1), said vehicle having an engine and a braking system, an accelerator (3) that conveys the driver'"'"'s wishes concerning acceleration to the engine, and a brake pedal that conveys the driver'"'"'s wishes concerning retardation to the braking system, which method comprises

taking into consideration several factors, such as a division of a specific driving distance into shorter segments, determining a speed profile (21a, 21b) for the driving distance, which speed profile comprises a relation between a speed set point and position, and

regularly reading the current speed set point from the speed profile,

characterised by the steps of

controlling the engine and the braking system on the basis of the speed set point,

by means of at least one actuator influencing the accelerator or braking pedal of the vehicle in accordance with said control,

determining whether the driver is applying a force on one of the pedals that is greater than a predetermined threshold value and, if such is the case, allowing the driver to override the influence of the actuator.

2. A method as claimed in claim 1, wherein the force the driver applies on a pedal is determined by the pedal being moved a specific distance against the action of a spring force.

3. A method as claimed in claim 1, wherein the force the driver applies on a pedal is determined by a piezo-electric element.

4. A method as claimed in claim 1, wherein the factors taken into consideration in the step of determining a speed profile comprise traffic-related factors such as speed limits and expected traffic congestion.

5. A method as claimed in claim 1, wherein the factors taken into consideration in the step of determining a speed profile comprise acceleration-related factors such as the incline of the road and bends in the road.

6. A method as claimed in claim 1, wherein the step of controlling the engine and the braking system on the basis of the speed set point is performed through direct influenced on the accelerator and the brake pedal.

7. A device for assisting a driver (4) of a vehicle (1), said vehicle having an engine and a braking system, an accelerator (3) that conveys the driver'"'"'s wishes concerning acceleration to the engine, and a brake pedal that conveys the driver'"'"'s wishes concerning retardation to the braking system, comprising means (5, 7, 8, 9) for determining a speed profile (21a, 21b) for a specific distance, which speed profile comprises a relation between a speed set point and position, characterised by

means (6) for controlling the engine and the braking system on the basis of the speed set point,

at least one actuator for influencing the accelerator or braking pedal of the vehicle in accordance with said control, and

means (20) for determining whether the driver is applying a force on one of the pedals that is greater than a predetermined threshold value in order, if such is the case, to override the influence of the actuator.

8. A device as claimed in claim 7, wherein the means for determining a speed profile and for conversion of the speed set point are implemented in the form of software in the control system of the vehicle.

9. A device as claimed in claim 7, wherein each pedal is arranged to be movable against spring action wherein a sensor is arranged to sense when one of the pedals is moved a certain distance.

10. A devise as claimed in claim 7, wherein a piezoelectric element is arranged on each pedal to sense when a force of a certain magnitude is applied on the pedal.

11. A method for determining a speed profile for a driving distance that is divided into segments, which speed profile comprises a relation between a speed set point and position, characterised by

creating a first profile (step 12) by associating each segment with a maximum suitable speed level,

smoothing out discontinuities arising between segments with different speeds (step 15),

calculating the time required to drive the driving distance according to the profile determined (step 16),

comparing this time with a predetermined time (step 17),

if said calculated time is less than said predetermined time, reducing the speed levels in the profile (step 18) until said times substantially coincide.