Trace generation device and working machine

• US 9,752,298 B2
• Filed: 01/07/2016
• Issued: 09/05/2017
• Est. Priority Date: 03/05/2015
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Nakamura, Satoshi, Egawa, Saku
• Primary Examiner(s): Dager, Jonathan M
• Application Number:
  US14/990,327
• Publication Number:
  US 20160258128A1
• Time in Patent Office: 607 Days
• Field of Search: None
• CPC Class Codes: E02F 3/43 Control of dipper or bucket position; Control of sequence of drive operations
• CPC Class Codes: E02F 3/437 providing automatic sequences of movements, e.g. linear excavation, keeping dipper angle constant
• CPC Class Codes: E02F 9/2029 Controlling the position of implements in function of its load, e.g. modifying the attitude of implements in accordance to vehicle speed control for hydraulic or pneumatic drives E02F9/2203, E02F9/2221 and E02F9/2253 take precedence
• CPC Class Codes: E02F 9/26 Indicating devices E02F5/145 takes precedence
• CPC Class Codes: E02F 9/265 with follow-up actions (e.g. control signals sent to actuate the work tool)

Abstract

In a trace generation device including a trace generation determination unit that outputs a command of trace generation, when a difference of an actual load applied to a bucket and a reference load is equal to or larger than a predetermined value during excavation and a candidate trace generation unit that generates a trace in which a work amount is almost constant, after the command is output, the reference load is an estimated load and the command of the trace generation is output when the difference of the actual load and the estimated load is equal to or larger than the predetermined value during the excavation. As a result, working efficiency can be raised while a trace in which an excavation amount is almost constant is generated.

Claims

1. A trace generation device comprising:

at least one processor for executing stored instructions to;

determine whether a difference of an actual load applied to a bucket and a reference load is equal to or larger than a predetermined value during excavation;

output a command of trace generation, when the difference is equal to or larger than the predetermined value; and

based on the output of the command of trace generation;

determine a position of an excavation start point a passage area, and a temporary maximum excavation depth,

determine a plurality of candidate traces by applying an excavation depth based on the position of the excavation start point the passage area, and the temporary maximum excavation depth, and

select a trace from the plurality of candidate traces in which a work amount is almost constant.

2. The trace generation device according to claim 1, wherein

the reference load is an estimated load, and

the at least one processor outputs the command of the trace generation, when the difference of the actual load and the estimated load is equal to or larger than the predetermined value during the excavation.

3. The trace generation device according to claim 1, wherein

the reference load is an allowed load, and

the at least one processor outputs the command of the trace generation, when the difference of the actual load and the allowed load is equal to or larger than the predetermined value during the excavation.

4. The trace generation device according to claim 1, wherein the at least one processor:

operates estimated loads of the plurality of candidate traces using load parameters, wherein the selection of the trace from the plurality of candidate traces is on the basis of the estimated loads;

controls the bucket according to the selected trace; and

updates the load parameters used for the operation of the estimated loads, using the actual load, wherein the at least one processor further;

generates the plurality of candidate traces in which a work amount is almost constant, using a current position of the bucket during work as the excavation start point, and

determines whether generation of the trace is necessary during the excavation, on the basis of the actual load acting on the bucket.

5. A working machine comprising the trace generation device according to claim 1.