Work machine

Patent metadata

Field	Value
Publication number	US-12227922-B2
Application number	US-202117912026-A
Country	US
Kind code	B2
Filing date	Feb 5, 2021
Priority date	Mar 27, 2020
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

A type of an object is determined and the movement direction of the object is predicted on the basis of a sensing result of the object sensed by an on-machine obstacle sensor. Information relating to the object that is the object sensed by the on-machine obstacle sensor and has been determined to have moved to the outside of a sensing range of the on-machine obstacle sensor is immediately deleted from an environment map on the basis of the type and the movement direction of the object. This can properly process information on the object that has gotten out of the sensing range, according to the cause of the object getting out of the sensing range.

First claim

The invention claimed is:

1. A work machine comprising:
a machine body having a moving device;
a work device disposed on the machine body;
a plurality of actuators that cause the moving device and the work device to operate;
an object sensor that senses an object around the machine body; and
a controller configured to:
create an environment map including information relating to an object that exists around the machine body on a basis of information on an object sensed by the object sensor and cause the plurality of actuators to operate on a basis of the environment map created,
determine a type of the object and predict a movement direction of the object on a basis of a sensing result of the object sensed by the object sensor, and
delete, from the environment map, the information relating to the object that is the object sensed by the object sensor and has been determined to have moved to outside of a sensing range of the object sensor on a basis of the type and the movement direction of the object, and
keep, in the environment map, the information relating to the object that is an object that has been sensed in a movable range of the machine body and the work device by the object sensor and whose type has been discriminated as a fixed object, and has been determined to have moved to the outside of the sensing range of the object sensor due to operation of the machine body and the work device.

2. A work machine comprising:
a machine body having a moving device;
a work device disposed on the machine body;
a plurality of actuators that cause the moving device and the work device to operate;
an object sensor that senses an object around the machine body; and
a controller configured to create an environment map including information relating to an object that exists around the machine body on a basis of information on an object sensed by the object sensor and cause the plurality of actuators to operate on a basis of the environment map created,
wherein the information relating to the object, the information being included in the environment map, includes an existence probability at a sensing position of the object, the existence probability being defined according to reliability of sensing by the object sensor, and
wherein the controller is configured to:
determine a type of the object and predict a movement direction of the object on a basis of a sensing result of the object sensed by the object sensor,
delete, from the environment map, the information relating to the object that is the object sensed by the object sensor and has been determined to have moved to outside of a sensing range of the object sensor on a basis of the type and the movement direction of the object, and
hold, for a certain time defined in advance, the information relating to the object in the environment map that is an object that has been sensed in the movable range of the machine body and the work device by the object sensor and whose type has been discriminated as a moving object, and has moved to the outside of the sensing range of the object sensor due to operation of the machine body and the work device, and thereafter gradually decrease the existence probability.

3. The work machine according to claim 2 ,
wherein the controller is configured to cause a holding time of the information relating to the object in the environment map to be shorter and cause a decrease speed of the existence probability to be faster when the existence probability of the object when the object is sensed by the object sensor is lower.

4. The work machine according to claim 2 ,
wherein the controller is configured to cause a holding time of the information relating to the object in the environment map to be shorter and cause a decrease speed of an existence probability to be faster when a distance to the object sensed by the object sensor from the machine body and the work device is longer.

5. The work machine according to claim 2 ,
wherein the controller is configured to cause a holding time of the information relating to the object in the environment map to be longer and cause a decrease speed of an existence probability to be slower when a movement speed of the object sensed by the object sensor is faster.

Assignees

• Hitachi Construction Mach Co

Inventors

• SAITO Yuho
• Moriki Hidekazu
• Imura Shinya
• Chiba Takaaki

Classifications

• G05D2105/05

  for soil shifting, building, civil engineering or mining, e.g. excavators · CPC title

• G05D1/242

  Means based on the reflection of waves generated by the vehicle (using passive navigation aids external to the vehicle G05D1/244; using signals provided by artificial sources external to the vehicle G05D1/247) · CPC title

• E02F9/24 Primary

  Safety devices {, e.g. for preventing overload (E02F9/226 takes precedence)} · CPC title

• E02F9/123

  Drives or control devices specially adapted therefor (E02F9/125 and E02F9/128 take precedence) · CPC title

• B60Y2200/412

  Excavators · CPC title