System and method for detecting obstacles in the path of a vehicle

• US 5,612,883 A
• Filed: 05/01/1995
• Issued: 03/18/1997
• Est. Priority Date: 02/05/1990
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Shaffer, Gary K., Whittaker, William L., Devier, Lonnie J., Lay, Norman K., Singh, Sanjiv J., Clow, Richard G., West, Jay H.
• Primary Examiner(s): PARK, COLLIN
• Application Number:
  US08/432,406
• Time in Patent Office: 687 Days
• Field of Search: 364/424.02, 364/460, 364/461, 364/561, 340/901, 340/904, 340/903, 340/435, 340/436, 340/437, 356/3, 356/4.01, 356/5.01, 356/5.02
• US Class Current: 701/300
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60K 31/04 and means for comparing one electrical quantity, e.g. voltage, pulse, waveform, flux, or the like, with another quantity of a like kind, which comparison means is involved in the development of an electrical signal which is fed into the controlling means
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 19/11 wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• CPC Class Codes: G01S 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
• CPC Class Codes: G01S 19/52 Determining velocity
• CPC Class Codes: G01S 5/009 Transmission of differential positioning data to mobile
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G05D 1/0011 associated with a remote control arrangement
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0268 using internal positioning means
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G05D 1/0278 : using satellite positioning signals, e.g. GPS
• CPC Class Codes: G05D 1/0297 : by controlling means in a control room
• CPC Class Codes: G08G 1/202 : Dispatching vehicles on the basis of a location, e.g. taxi dispatching

Abstract

A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).

Claims

1. A scanning system, mounted on a vehicle, for detecting an object in a path of said vehicle, comprising:

means for producing a beam of energy;

means for scanning said beam of energy through a desired range of angles relative to said vehicle;

means for measuring a distance between said vehicle and the object in the path of said vehicle, comprised of;

means for detecting reflected energy, said reflected energy being produced by a reflection of said beam off of the object,

means for storing information associated with said reflected energy, and

means for processing the associated information to calculate a distance said reflected energy has traveled; and

means for disabling said producing means during a portion of said desired range of angles so that only a fraction of said desired range of angles is scanned and an amount of the associated information that is stored is minimized.

2. The scanning system of claim 1, wherein said means for measuring a distance between said vehicle and the object further comprises:

means for detecting substantial impairment of said scanning means.

3. The scanning system of claim 2, further comprising means for disabling said producing means if the operation of said scanning means is substantially impaired.

4. The scanning system of claim 1, further comprising:

means for varying said scanning in number of scans per unit time.

5. The scanning system of claim 1, further comprising:

means for varying a number of distance measurements per scan, thereby varying scanner resolution.

6. The scanning system of claim 1, wherein said storing means further comprises:

means for converting said stored information into a plurality of TTL signals;

means for converting each of said plurality of TTL signals to a differential type signal;

means for transmitting each of said differential type signals to a temporary storage buffer; and

means for transmitting each of said differential type signals from said storage buffer to a host processing system.

7. A scanning method of detecting an object in a path of a vehicle, using a scanner mounted on said vehicle, comprising the steps of:

(1) producing a beam of energy;

(2) scanning said beam of energy through a desired range of angles relative to said vehicle;

(3) measuring a distance between said vehicle and the object in the path of said vehicle, comprising the steps of;

(a) detecting reflected energy, said reflected energy being produced by a reflection of said beam off of the object,

(b) storing information associated with said reflected energy, and

(c) processing the associated information to calculate a distance said reflected energy has traveled; and

(4) disabling said step of producing during a portion of said desired range of angles so that only a fraction of said desired range of angles is scanned and an amount of the associated information that is stored is minimized.

8. The scanning method of claim 7, wherein said step of measuring a distance between said vehicle and the object in the path of said vehicle further comprises:

(d) detecting substantial impairment of said step of scanning.

9. The scanning method of claim 8, further comprising:

(5) disabling said step of producing a beam of energy if operation of said step of scanning is substantially impaired.

10. The scanning method of claim 7, further comprising:

(d) varying said scanning in number of scans per unit time.

11. The scanning method of claim 7, further comprising:

(d) varying a number of distance measurements per scan, thereby varying scanner resolution.

12. The scanning method of claim 7, wherein said step (b) of storing information associated with said reflected energy comprises:

(i) converting said stored information into a plurality of TTL signals;

(ii) converting each of said plurality of TFL signals to a differential type signal;

(iii) transmitting each of said differential type signals to a temporary storage buffer; and

(iv) transmitting each of said differential type signals from said storage buffer to a host processing system.