Object height estimation using ultrasonic sensors

Patent metadata

Field	Value
Publication number	US-12306355-B2
Application number	US-202318190437-A
Country	US
Kind code	B2
Filing date	Mar 27, 2023
Priority date	Mar 27, 2023
Publication date	May 20, 2025
Grant date	May 20, 2025

Abstract

A disclosure is presented for estimating height of an object using ultrasonic sensors carried onboard a vehicle. The height may be estimated by generating ultrasonic distance measurements based on a time of flight associated with ultrasonic reflections detected with the ultrasonic sensors, generating a three-dimensional (3D) occupancy grid to volumetrically represent at least a portion of an environment within field of view of the ultrasonic sensors, the 3D occupancy grid including a plurality of volumetric pixels (voxels), assigning a count value to each of the voxels based on the distance measurements, and estimating the height according to a relative spatial relationship between the vehicle and the voxel having the count value with a greatest value.

First claim

What is claimed is:

1. A system for object height estimation using ultrasonic sensors, comprising:
a vehicle;
a plurality of ultrasonic sensors onboard the vehicle, the ultrasonic sensors including:
a transmitter configured for emitting ultrasonic sound waves outwardly into an environment of the vehicle; and
a receiver configured for receiving ultrasonic reflections from an object within the environment reflecting the sound waves;

a height estimation module onboard the vehicle, the height estimation module configured for:
generating ultrasonic distance measurements based on a time of flight of the ultrasonic reflections, the distance measurements representing a relative distance between the object and the receiver receiving the corresponding ultrasonic reflection;
generating a three-dimensional (3D) occupancy grid to volumetrically represent at least a portion of the environment, the 3D occupancy grid including a plurality of volumetric pixels (voxels) to define equal units of volumetric space;
assigning a count value to each of the voxels based on the distance measurements, the count values representing a probabilistic prediction of the object being present within the volumetric space of the corresponding voxel; and
estimating a height of the object according to a relative spatial relationship between the vehicle and the voxel having the count value with a greatest value.

2. The system according to claim 1 , wherein:
the height estimation module is configured for estimating the height based on generating the distance measurements on an interval-by-interval basis for a plurality of intervals, the intervals occurring while the vehicle is in motion toward the object, each successive interval corresponding with the vehicle moving closer to the object.

3. The system according to claim 2 , wherein:
the height estimation module is configured for incrementing on the interval-by-interval basis the count value assigned to each voxel spatially overlapping with one of the distance measurements.

4. The system according to claim 3 , wherein:
the height estimation module is configured for decrementing on the interval-by-interval basis the count value assigned to each voxel spatially non-overlapping with one of the distance measurements.

5. The system according to claim 4 , wherein:
the height estimation module is configured for incrementing the voxels by a constant value.

6. The system according to claim 5 , wherein:
the height estimation module is configured for decrementing the voxels by a proportional value.

7. The system according to claim 6 , wherein:
the proportional value is represented as:

P
=

f
⁡
(

D
-

(

x
-

x
v

)

2

+

(

y
-

y
v

)

2

⁢

(

z
-

z
v

)

2

)

where P is the proportional value, D corresponds with one of the distance measurements, x, y, z correspond with the location of the vehicle, x v , y v , z v correspond with the location of the corresponding voxel relative to the location of the vehicle and ƒ is a monotonically increasing function.

8. The system according to claim 3 , wherein:
the height estimation module is configured for determining the distance measurements as overlapping with the voxels having a portion thereof within a predefined spatial relationship to the corresponding distance measurement.

9. The system according to claim 8 , wherein:
the predefined spatial relationship is represented as:

D
-
ε

<

(

x
-

x
v

)

2

+

(

y
-

y
v

)

2

⁢

(

z
-

z
v

)

2

<

D
+
ε

where D corresponds with one of the distance measurements, ε corresponds with a constant approximately equal to the volumetric space of each voxel, x, y, z correspond with a location of the vehicle, and x v , y v , z v correspond with a location of the corresponding voxel.

10. The system according to claim 2 , wherein:
the distance measurements corresponding with a spherical distance from the corresponding receiver.

11. The system according to claim 10 , wherein:
the distance measurements are incapable of representing a direction to the object with more specificity than a field of view of the corresponding receiver.

12. A method for object height estimation using ultrasonic sensors onboard a vehicle, comprising:
generating ultrasonic distance measurements based on a time of flight associated with ultrasonic reflections detected with the ultrasonic

Assignees

• Gm Global Tech Operations Llc

Inventors

• Baltaxe Michael
• Slutsky Michael
• Rubanenko Ariel
• Levi Dan

Classifications

• G01S15/89

  for mapping or imaging · CPC title

• G01S2015/938

  in the bumper area · CPC title

• G01S15/931

  of land vehicles · CPC title

• G01S7/539 Primary

  using analysis of echo signal for target characterisation; Target signature; Target cross-section · CPC title

• G01S15/08 Primary

  Systems for measuring distance only (indirect measurement G01S15/46) · CPC title