Apparatus for controlling speed of mobile object

• US 20120046803A1
• Filed: 08/22/2011
• Published: 02/23/2012
• Est. Priority Date: 08/23/2010
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Inou, Hiroshi, Sawada, Mamoru, Totsuka, Seiji
• Granted Patent: US 8,489,252 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: A61B 5/163 by tracking eye movement, gaze, or pupil change
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: B60W 2540/22 Psychological state; Stress level or workload
• 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 2554/80 Spatial relation or speed relative to objects
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: G06V 20/597 Recognising the driver's state or behaviour, e.g. attention or drowsiness
• CPC Class Codes: G06V 40/19 Sensors therefor

Abstract

In an obtainer for obtaining speed feeling of a driver of a movable object, a gaze point setter sets a gaze point of the driver, and a motion detector detects relative motion of an environmental field around the mobile object with respect to the mobile object. A divergent component calculator projects the relative motion of the environmental field in a coordinate system. The coordinate system is formed by modeling a retina sphere of the driver of the mobile object. The divergent calculator calculates each of divergent components of the projected relative motion of the environmental field radially expanding from the gaze point. A speed feeling calculator calculates speed feeling of the driver based on the divergent components of the projected relative motion of the environmental field radially expanding from the gaze point calculated by the divergent component calculator.

Claims

1. An obtainer for obtaining speed feeling of a driver of a movable object, the obtainer comprising:

a gaze point setter that sets a gaze point of the driver of the mobile object;

a motion detector that detects relative motion of an environmental field around the mobile object with respect to the mobile object;

a divergent component calculator that;

projects the relative motion of the environmental field in a coordinate system, the coordinate system being formed by modeling a retina sphere of the driver of the mobile object, and

calculates each of divergent components of the projected relative motion of the environmental field radially expanding from the gaze point; and

a speed feeling calculator that calculates speed feeling of the driver based on the divergent components of the projected relative motion of the environmental field radially expanding from the gaze point calculated by the divergent component calculator.

2. The obtainer according to claim 1, wherein the speed feeling calculator comprises, as the speed feeling of the driver, a total calculator that calculates a total of at least a number of the divergent components of the projected relative motion of the environmental field, the at least the number of the divergent components being included in a predetermined area containing the gaze point.

3. A speed control apparatus for a mobile object, the apparatus comprising:

a gaze point setter that sets a gaze point of a driver of the mobile object;

a motion detector that detects relative motion of an environmental field around the mobile object with respect to the mobile object;

a divergent component calculator that;

projects the relative motion of the environmental field in a coordinate system, the coordinate system being formed by modeling a retina sphere of the driver of the mobile object, and

calculates each of divergent components of the projected relative motion of the environmental field radially expanding from the gaze point;

a total calculator that calculates a total of at least a number of the divergent components of the projected relative motion of the environmental field, the at least the number of the divergent components being included in a predetermined area containing the gaze point; and

a controller that controls the speed of the mobile object such that the total of the at least a number of the divergent components of the projected relative motion of the environmental field is substantially kept constant.

4. The speed control apparatus according to claim 3, wherein the motion detector is configured to set a plurality of points in the predetermined area, and detect relative motion of each of the plurality of points with respect to the mobile object as the relative motion of the environmental field around the mobile object.

5. The speed control apparatus according to claim 3, wherein the mobile object has a windshield, and the predetermined area is set to be an area viewable by the driver through the windshield of the mobile object.

6. The speed control apparatus according to claim 4, wherein the mobile object is a vehicle that travels on a road, the motion detector comprises:

a road map storing unit that stores therein data of road map;

a current position detector that detects a current position of the vehicle; and

a vehicle-motion detector that detects motion of the vehicle in a lateral direction of the vehicle, and detects motion of the vehicle in a vertical direction of the vehicle,

the motion detector being configured to define, as the environmental field around the vehicle, a running environmental field around the vehicle based on the data of the road map and the detected current position of the vehicle, and detect the relative motion of each of the plurality of points with respect to the mobile object in the running environmental field based on the detected motion of the vehicle in the lateral direction and the detected motion of the vehicle in the vertical direction.

7. The speed control apparatus according to claim 3, wherein the motion detector further comprises a position detector that detects a position of a stationary object existing in the environmental field as a parameter indicative of the environmental field, and detects the relative motion of the environmental field based on the detected position of the stationary object.

8. The speed control apparatus according to claim 3, wherein the gaze point setter is configured to set, as the gaze point, a point of the projected relative motion of the environmental field, the point of the projected relative motion of the environmental field is minimum relative motion in comparison to another point of the projected relative motion of the environmental field.

9. The speed control apparatus according to claim 3, further comprising a driver camera that picks up an image of the driver, the image including at least one eye of the driver, and the gaze point setter is configured to analyze the image, and set the gaze point based on a result of the analysis of the image.

10. The speed control apparatus according to claim 3, further comprising a front camera successively pick up images in a travelling direction of the vehicle, and the gaze point setter is configured to set the gaze point based on optical flows in each of the picked-up images.

11. The speed control apparatus according to claim 3, wherein the controller is configured to start control of the speed of the mobile object in response to when an instruction is inputted by the driver of the mobile object, set, as a target value, a value of the total of the at least a number of the divergent components of the projected relative motion of the environmental field calculated by the total calculator when the instruction is inputted by the driver of the mobile object, and control the speed of the mobile object such that:

a value of the total of the at least a number of the divergent components of the projected relative motion of the environmental field calculated by the total calculator after calculation of the target value is substantially matched with the target value.

12. The speed control apparatus according to claim 11, wherein the controller is configured to, after the start of control of the speed of the mobile object, update the target value each time an instruction to change the speed of the vehicle is inputted from the driver.

13. The speed control apparatus according to claim 11, wherein the controller is configured to adjust the speed of the mobile object to a first value at which the total of the at least a number of the divergent components of the projected relative motion of the environmental field is substantially kept constant, and, when a speed adjusting member for adjusting the speed of the mobile object to a second value is operated by the driver after the start of control of the speed of the mobile object, the controller is configured to adjust the speed of the vehicle to be one of the first value and the second value, the one of the first value and the second value being lower than the other thereof.