Method of Providing a Dynamic Region of interest in a LIDAR System
A system and method for providing a dynamic region of interest in a lidar system can include scanning a light beam over a field of view to capture a first lidar image, identifying a first object within the captured first lidar image, selecting a first region of interest within the field of view that contains at least a portion of the identified first object, and capturing a second lidar image, where capturing the second lidar image includes scanning the light beam over the first region of interest at a first spatial sampling resolution, and scanning the light beam over the field of view outside of the first region of interest at a second spatial sampling resolution, wherein the second sampling resolution is less than the first spatial sampling resolution.
The present disclosure relates to systems and methods for providing a dynamic region of interest in a LIDAR system.
BACKGROUNDCertain lidar systems include a laser that can be discretely scanned over a series of points in a target region and a detector that can detect a reflected portion of the discretely scanned laser, such as to provide an image of the target region. An angular resolution of the lidar system can depend on the number of points that can be scanned by the laser within a field of view of the lidar system.
SUMMARY OF THE DISCLOSUREIn certain lidar systems with a large field of view and a very fine angular resolution, thermal management of the lidar system and receive-side analog-to-digital conversion circuitry can present design challenges. In an example, a large field of view can include a ±30° horizontal field of view and a ±0.6° vertical field of view, a very fine angular resolution can include a 0.1° horizontal angular resolution and a 0.2° vertical angular resolution, and the lidar system can include a 20 Hz frame update rate. In such an example, the lidar system can scan 540,000 points per second, and can correspond to an average laser power of 720 mW for a laser outputting 1 μJ per pulse. An average laser power of 720 mW can be high enough to cause considerable thermal design challenges. In an example where multiple laser pulses can be used for each point in a 2D field of view, the average laser power can be much higher. For example, if five pulses per point in the 2D field of view are used, the average laser power can be 3.6 W. The inventors have recognized, among other things, that it is possible to reduce a number of points scanned per lidar image, such as by providing varying spatial resolution in the lidar images, such as to overcome difficulties with thermal management and receive-side electronics. Further features of the disclosure are provided in the appended claims, which features may optionally be combined with each other in any permutation or combination, unless expressly indicated otherwise elsewhere in this document.
In an aspect, the disclosure can feature a method for providing a dynamic region of interest, such as in a lidar system. The method can include scanning a light beam over a field of view, such as to capture a first lidar image. The method can also include identifying a first object, such as within the captured first lidar image. The method can also include selecting a first region of interest, such as within a field of view that contains at least a portion of the identified first object. The method can also include capturing a second lidar image, where capturing the second lidar image can include scanning the light beam over the first region of interest, such as at a first spatial sampling resolution and scanning the light beam over the field of view outside of the first region of interest, such as at a second spatial sampling resolution, wherein the second sampling resolution can be different than the first spatial sampling resolution. In an example, the second sampling resolution can be less than the first spatial sampling resolution. The method can also include identifying a second object, such as can be outside of the first region of interest, selecting a second region of interest that can contain at least a portion of the identified second object, and capturing a third lidar image, where capturing the third lidar image can include scanning the light beam over the first region of interest and the second region of interest at the first spatial sampling resolution and scanning the light beam over the field of view outside of both the first region of interest and the second region of interest at a third spatial sampling resolution, where the third sampling resolution can be different than the second spatial sampling resolution. In an example, the third sampling resolution can be less than the second spatial sampling resolution. In an example, the second object can be identified outside of the first region of interest using the captured second lidar image. The method can also include detecting a movement of the identified first object, and adjusting a characteristic of the first region of interest, such as in response to the detected movement of the identified first object. The method can also include adjusting a size of the first region of interest, such as in response to the detected movement of the identified first object. The method can also include adjusting a size and position of the first region of interest in response to the detected movement of the identified first object. The method can also include detecting a change in the size of the identified first object and adjusting a size of the first region of interest, such as to accommodate the detected change in size of the identified first object. The method can also include reducing a second spatial sampling resolution, such as in response to an increase in the size of the first region of interest. The method can also include increasing a second spatial sampling resolution, such as in response to a decrease in the size of the first region of interest. The method can also include scanning the light beam over the field of view to capture successive lidar images, wherein the region of interest is capable of being adjusted after the capture of each successive lidar image. The method can also include identifying a second object outside of the first region of interest, selecting a second region of interest that can contain at least a portion of the identified second object, and capturing a third lidar image, where capturing the third lidar image can include scanning the light beam over the first region of interest at the first spatial sampling resolution, scanning the light beam over the second region of interest at a third spatial sampling resolution, and scanning the light beam over the field of view outside of the first region of interest and the second region of interest, at the second spatial sampling resolution, wherein the third sampling resolution can be different than the first spatial sampling resolution. In an example, the third sampling resolution can be less than the second spatial sampling resolution. In an example, the second object can be identified outside of the first region of interest by using the captured second lidar image. Identifying a first object within the captured first lidar image can include detecting at least one edge of the first object. Identifying a first object within the captured first lidar image can include detecting at least one lane marker.
In an aspect, the disclosure can feature a system for providing a dynamic region of interest in a lidar system. The system can include a laser configured to emit a light beam, such as towards a target region. The system can also include control circuitry configured to instruct an optical system to scan the light beam over the target region. The system can also include an optical system having a field of view and can configured to direct a portion of the light beam received from the target region. The system can also include a photodetector configured to receive the portion of the light beam directed from the optical system, such as to form a first lidar image. The system can also include detection circuitry that can be configured to identify a first object within the first lidar image. The control circuitry can be further configured to select a first region of interest within the field of view that can contain at least a portion of the identified first object, instruct the optical system to scan the light beam over the first region of interest at a first spatial sampling resolution, and instruct the optical system to scan the light beam over the field of view outside of the first region of interest at a second spatial sampling resolution that can be different than the first spatial sampling resolution. In an example, the first spatial sampling resolution can be less than the second spatial sampling resolution. The photodetector can be further configured to receive a corresponding portion of the light beam to form a second lidar image. The detection circuitry can be further configured to identify a second object outside of the first region of interest in the second lidar image. The control circuitry can be further configured to select a second region of interest that can contain a portion of the identified second object, instruct the optical system to scan the light beam over the first region of interest and the second region of interest at the first spatial sampling resolution, and instruct the optical system to scan the light beam over the field of view outside of both the first region of interest and the second region of interest at a third spatial sampling resolution that can be different than the first spatial sampling resolution. In an example, the third spatial sampling resolution can be less than the first spatial sampling resolution. The detection circuitry can be further configured to detect a movement of the identified first object and the control circuitry can be configured to adjust a characteristic of the first region of interest, such as in response to the detected movement of the identified first object. The control circuitry can be further configured to adjust a size of the first region of interest, such as in response to the detected movement of the identified first object. The control circuitry can be further configured to adjust a size and position of the first region of interest, such as in response to the detected movement of the identified first object. The detection circuitry can be further configured to detect a change in the size of the identified first object and the control circuitry can be further configured to adjust a size of the first region of interest, such as to accommodate the detected change in size of the identified first object. The control circuitry can be further configured to reduce the second spatial sampling resolution, such as in response to an increase in the size of the first region of interest. The control circuitry can be further configured to increase the second spatial sampling resolution, such as in response to a decrease in the size of the first region of interest.
In an aspect, the disclosure can feature a system for providing a dynamic region of interest in a lidar system. The system can include a means for scanning a light beam over a field of view, such as to capture a first lidar image. The means for scanning can include control circuitry and a scanning laser, such as control circuitry 104 and scanning laser 106 as shown in
The present disclosure will now be described, by way of example, with reference to the accompanying drawings, in which:
Claims
1. A method for providing a dynamic region of interest in a lidar system, the method comprising:
- scanning a light beam over a field of view to capture a first lidar image;
- identifying a first object within the captured first lidar image;
- selecting a first region of interest within the field of view that contains at least a portion of the identified first object; and
- capturing a second lidar image, where capturing the second lidar image includes: scanning the light beam over the first region of interest at a first spatial sampling resolution; and scanning the light beam over the field of view outside of the first region of interest at a second spatial sampling resolution, wherein the second sampling resolution is different than the first spatial sampling resolution.
2. The method of claim 1 further comprising:
- identifying a second object outside of the first region of interest;
- selecting a second region of interest that contains at least a portion of the identified second object; and
- capturing a third lidar image, where capturing the third lidar image includes: scanning the light beam over the first region of interest and the second region of interest at the first spatial sampling resolution; and scanning the light beam over the field of view outside of both the first region of interest and the second region of interest at a third spatial sampling resolution, wherein the third sampling resolution is different than the first spatial sampling resolution.
3. The method of claim 1 further comprising:
- detecting a movement of the identified first object; and
- adjusting a characteristic of the first region of interest in response to the detected movement of the identified first object.
4. The method of claim 3 comprising adjusting a size of the first region of interest in response to the detected movement of the identified first object.
5. The method of claim 3 comprising adjusting a size and position of the first region of interest in response to the detected movement of the identified first object.
6. The method of claim 1 further comprising:
- detecting a change in the size of the identified first object; and
- adjusting a size of the first region of interest to accommodate the detected change in size of the identified first object.
7. The method of claim 6 comprising reducing a second spatial sampling resolution in response to an increase in the size of the first region of interest.
8. The method of claim 6 comprising increasing a second spatial sampling resolution in response to a decrease in the size of the first region of interest.
9. The method of claim 1 further comprising scanning the light beam over the field of view to capture successive lidar images, wherein the region of interest is capable of being adjusted after the capture of each successive lidar image.
10. The method of claim 1 further comprising:
- identifying a second object outside of the first region of interest;
- selecting a second region of interest that contains at least a portion of the identified second object; and
- capturing a third lidar image, where capturing the third lidar image includes: scanning the light beam over the first region of interest at the first spatial sampling resolution; scanning the light beam over the second region of interest at a third spatial sampling resolution; and scanning the light beam over the field of view outside of the first region of interest and the second region of interest at the second spatial sampling resolution, wherein the third sampling resolution is different than the second spatial sampling resolution.
11. The method of claim 1 wherein identifying a first object within the captured first lidar image includes detecting at least one edge of the first object.
12. The method of claim 1 wherein identifying a first object within the captured first lidar image includes detecting at least one lane marker.
13. A system for providing a dynamic region of interest in a lidar system, the system comprising:
- a laser configured to emit a light beam towards a target region;
- control circuitry configured to instruct an optical system to scan the light beam over the target region;
- an optical system having a field of view and configured to direct a portion of the light beam received from the target region;
- a photodetector configured to receive the portion of the light beam directed from the optical system to form a first lidar image; and
- detection circuitry configured to identify a first object within the first lidar image; wherein
- the control circuitry is further configured to select a first region of interest within the field of view that contains at least a portion of the identified first object, instruct the optical system to scan the light beam over the first region of interest at a first spatial sampling resolution, and instruct the optical system to scan the light beam over the field of view outside of the first region of interest at a second spatial sampling resolution different than the first spatial sampling resolution, and wherein the photodetector is further configured to receive a corresponding portion of the light beam to form a second lidar image.
14. The system of claim 13 wherein the detection circuitry is further configured to identify a second object outside of the first region of interest, the control circuitry is further configured to select a second region of interest that contains a portion of the identified second object, instruct the optical system to scan the light beam over the first region of interest and the second region of interest at the first spatial sampling resolution, and instruct the optical system to scan the light beam over the field of view outside of both the first region of interest and the second region of interest at a third spatial sampling resolution different than the first spatial sampling resolution.
15. The system of claim 13 wherein the detection circuitry is further configured to detect a movement of the identified first object and the control circuitry is configured to adjust a characteristic of the first region of interest in response to the detected movement of the identified first object.
16. The system of claim 15 wherein the control circuitry is further configured to adjust a size of the first region of interest in response to the detected movement of the identified first object.
17. The system of claim 15 wherein the control circuitry is further configured to adjust a size and position of the first region of interest in response to the detected movement of the identified first object.
18. The system of claim 13 wherein the detection circuitry is further configured to detect a change in the size of the identified first object and the control circuitry is further configured to adjust a size of the first region of interest to accommodate the detected change in size of the identified first object.
19. The system of claim 18 wherein the control circuitry is further configured to reduce the second spatial sampling resolution in response to an increase in the size of the first region of interest.
20. A system for providing a dynamic region of interest in a lidar system, the system comprising:
- means for scanning a light beam over a field of view to capture a first lidar image;
- means for identifying a first object within the captured first lidar image;
- means for selecting a first region of interest within the field of view that contains at least a portion of the identified first object; and
- means for capturing a second lidar image, where capturing the second lidar image includes: scanning the light beam over the first region of interest at a first spatial sampling resolution; and scanning the light beam over the field of view outside of the first region of interest at a second spatial sampling resolution, wherein the second sampling resolution is different than the first spatial sampling resolution.
Type: Application
Filed: Apr 20, 2017
Publication Date: Oct 25, 2018
Inventors: Ronald A. Kapusta (Carlisle, MA), Benjamin Luey (Denver, CO), Harvy Weinberg (Sharon, MA), Scott R. Davis (Denver, CO), Michael H. Anderson (Lyons, CO), Scott D. Rommel (Lakewood, CO)
Application Number: 15/492,771