Velocity calculation apparatus, control method, program and storage medium

Patent metadata

Field	Value
Publication number	US-11203349-B2
Application number	US-201616330038-A
Country	US
Kind code	B2
Filing date	Sep 2, 2016
Priority date	Sep 2, 2016
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

If a controller determines the calculation of a measured vehicle body velocity is possible, the controller calculates the measured vehicle body velocity as an estimated vehicle body velocity to conduct update processing for a K table and an AB table. If the controller determines the calculation of the measured vehicle body velocity is impossible, the controller extracts a conversion coefficient from the K table based on a detected running state while extracting a sensitivity coefficient and an offset coefficient from the AB table based on the temperature by a temperature sensor. The vehicle mounted apparatus calculates an axle pulse-based vehicle body velocity from the extracted conversion coefficient while calculating an acceleration-based vehicle body velocity from the extracted sensitivity coefficient and offset coefficient. The vehicle mounted apparatus calculates the estimated vehicle body velocity by weighting the calculation values of the axle pulse-based vehicle body velocity and the acceleration-based vehicle body velocity.

First claim

The invention claimed is:

1. A velocity calculation apparatus comprising:
an acquisition unit configured to acquire measured vehicle body velocity of a moving body and moving body information on the moving body, the measured vehicle body velocity being based on measurement information outputted by a measurement device which measures surroundings of the moving body;
a storage unit storing calculation values for calculating a velocity of the moving body, each of the calculation values being associated with moving body information on the moving body; and
a controller configured,
at a time when the measured vehicle body velocity can be acquired, to determine an estimated velocity of the moving body as the measured vehicle body velocity, and
at a time when the measured vehicle body velocity cannot be acquired, to calculate the estimated velocity based on the moving body information acquired by the acquisition unit and a corresponding calculation value that is among the calculation values, the corresponding calculation value corresponding to the moving body information acquired by the acquisition unit.

2. The velocity calculation apparatus according to claim 1 ,
wherein, at the time when the measured vehicle body velocity can be acquired, the controller updates, on a basis of the measured vehicle body velocity, a calculation value to be stored on the storage unit in a state of being associated with the moving body information acquired by the acquisition unit.

3. The velocity calculation apparatus according to claim 2 ,
wherein, at the time when the measured vehicle body velocity can be acquired, the controller stores, on the storage unit in a state of being associated with the moving body information acquired by the acquisition unit, a calculation value that is an average of a calculation value calculated based on the measured vehicle body velocity and a calculation value already stored on the storage unit in a state of being associated with the moving body information acquired by the acquisition unit.

4. The velocity calculation apparatus according to claim 2 ,
wherein, through an interpolation of calculation values corresponding to the moving body information which is associated with the calculation values, the controller calculates a calculation value to be associated with the moving body information which is not associated with a calculation value on the storage unit.

5. The velocity calculation apparatus according to claim 1 ,
wherein the storage unit stores, as a calculation value, at least one of a first coefficient for calculating a third velocity of the moving body based on a wheel rotating speed of the moving body or a second coefficient for calculating a fourth velocity of the moving body based on an acceleration of the moving body, and
wherein, at the time when the measured vehicle body velocity cannot be acquired, the controller determines the estimated velocity based on at least one of the third velocity or the fourth velocity.

6. The velocity calculation apparatus according to claim 5 ,
wherein the acquisition unit acquires, as the moving body information, at least one of information indicative of a running state of the moving body or temperature information,
wherein, in a case where the acquisition unit acquires the information indicative of the running state, the controller calculates the third velocity by retrieving a first coefficient corresponding to the running state from the storage unit, and
wherein, in a case where the acquisition unit acquires the temperature information, the controller calculates the fourth velocity by retrieving a second coefficient corresponding to temperature indicated by the temperature information from the storage unit.

7. The velocity calculation apparatus according to claim 5 ,
wherein the storage unit stores at least one of a first table or a second table, the first table indicating a first coefficient per combination of an acceleration, a gradient angle and a wheel rotating speed, the second table indicating a second coefficient per temperature.

8. The velocity calculation apparatus according to claim 5 ,
wherein, after calculating the third velocity and the fourth velocity, the controller calculates the estimated velocity by weighting the third velocity and the fourth velocity based on a time that has elapsed since the first coefficient used for calculation of the third velocity was recorded in the storage unit and a time that has elapsed since the second coefficient used for calculation of the fourth velocity was recorded in the storage unit.

9. The velocity calculation apparatus according to claim 1 ,
wherein the acquisition unit acquires information outputted by an external sensor as the information on surroundings of the moving body, and
wherein, at a time of detecting a feature whose position information is stored on the storage unit through the information outputted by the external sensor, the controller determines that the measured vehicle body velocity can be acquired.

10. A control method executed by a velocity calculation apparatus which includes a storage unit storing calculation values for calculating a velocity of a moving body, each of the calculation values being associated with moving body information on the moving body, the control method comprising:
acquiring measured vehicle body velocity of the moving body and moving body information on the moving body, the measured vehicle body velocity being based on measurement information outputted by a measurement device which measures surroundings of the moving body;
a control process,
at a time when the measured vehicle body velocity can be acquired, determining an estimated velocity of the moving body as the measured vehicle body velocity, and
at a time when the measured vehicle body velocity cannot be acquired, calculating the estimated velocity based on the moving body information acquired by the acquisition process and a corresponding calculation value that is among the calculation values, the corresponding calculation value corresponding to the moving body information acquired by the acquisition.

11. A non-transitory computer readable medium including instructions executed by a computer of a velocity calculation apparatus which includes a storage unit storing calculation values for calculating a velocity of a moving body, each of the calculation values being associated with moving body information on the moving body, the instructions comprising:
acquiring measured vehicle body velocity of the moving body and moving body information on the moving body, the measured vehicle body velocity being based on measurement information outputted by a measurement device which measures surroundings of the moving body;
a controller configured,
at a time when the measured vehicle body velocity can be acquired, determining an estimated velocity of the moving body as the measured vehicle body velocity, and
at a time when the measured vehicle body velocity cannot be acquired, calculating the estimated velocity based on the moving body information acquired by the acquisition unit and a corresponding calculation value that is among the calculation values, the corresponding calculation value corresponding to the moving body information acquired by the acquisition.

Assignees

• Pioneer Corp

Inventors

• Kato Masahiro
• Niihara Ryoko

Classifications

• G01C21/1652

  with ranging devices, e.g. LIDAR or RADAR · CPC title

• B60W40/105 Primary

  Speed · CPC title

• G01P3/50

  for measuring linear speed (G01P3/56 takes precedence) · CPC title

• G01P3/42

  Devices characterised by the use of electric or magnetic means (G01P3/66 takes precedence; measuring electric or magnetic values in general G01R) · CPC title

• B60W2520/28

  Wheel speed · CPC title