METHOD FOR DETERMINING AND/OR COMPENSATING RANGE OFFSET OF A RANGE SENSOR

• US 20140098358A1
• Filed: 10/08/2013
• Published: 04/10/2014
• Est. Priority Date: 10/08/2012
• Status: Active Grant

• Current Assignee: Melexis Technologies NV (Sensinnovat BVBA)
• Original Assignee: Melexis Technologies NV (Sensinnovat BVBA)
• Inventors: KOERS, Gaetan
• Granted Patent: US 9,606,232 B2
• Time in Patent Office: Days
• US Class Current: 356/5.01
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating

Abstract

A method for compensating range offset of a range sensor located in a predetermined position in a spatial environment and comprising a pixel array adapted for measuring a distance, the spatial environment comprising at least two stationary reference positions located at predetermined reference distances, the method comprising the steps of: a) determining distance values to the reference positions; b) calculating differences between the distance values and the corresponding reference distances; c) determining a range offset value as the maximum of the differences; d) measuring distance values to positions within the spatial environment using the pixel array; e) correcting the measured distance values by subtracting the determined in-situ range offset value from each of the measured distance values.

Claims

1. Method for determining a range offset of a range sensor, the range sensor having a predetermined position in a spatial environment and comprising a pixel array adapted for measuring a distance of each pixel of the pixel array to a corresponding position in the spatial environment, the spatial environment comprising at least two stationary reference positions, a first resp. second reference position located at a first resp. second predetermined reference distance from the range sensor, the method comprising:

a) determining a distance value to each of the at least two reference positions using the pixel array;

b) calculating at least two differences between each determined distance value and the corresponding predetermined reference distance of the at least two reference positions;

c) determining an in-situ range offset value of the range sensor by calculating the maximum of the at least two differences.

2. The method according to claim 1, where the spatial environment is the inner space of the cabin of a vehicle.

3. A method for compensating range offset of a range sensor, the range sensor having a predetermined position in a spatial environment and comprising a pixel array adapted for measuring a distance of each pixel of the pixel array to a corresponding position in the spatial environment, the spatial environment comprising at least two stationary reference positions, a first resp. second reference position located at a first resp. second predetermined reference distance from the range sensor, the method comprising the steps of:

a) determining a range offset of the range sensor according to any of the previous claims;

b) measuring a plurality of distance values to positions within the spatial environment using the pixel array;

c) correcting the measured distance values by subtracting the determined in-situ range offset value from each of the measured distance values.

4. The method according to claim 3, where the spatial environment is the inner space of the cabin of a vehicle.

5. The method according to claim 3, where the spatial environment is a space outside of a vehicle, comprising at least part of a bumper of said vehicle.

6. A range sensor comprising:

a pixel array comprising a plurality of pixels, and adapted for measuring a distance of each pixel of the pixel array to a corresponding position in a spatial environment,

a memory for storing at least two predetermined reference distances;

an evaluation unit comprising a program for performing the method of any of the previous claims.

7. A vehicle comprising the range sensor according to claim 6.