Forklift Reverse Travel Control for Obstacle Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Industrial vehicles face deteriorated workability due to simultaneous imposition of multiple vehicle speed limiting functions, which hinder avoidance operations when different controls impose conflicting speed limits.
Innovation Solution
Implementing a starting permission control unit to set a limit value that allows travel, preventing interference from secondary controls, thus ensuring the avoidance operation is not hindered.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple vehicle speed limiting controls are performed in parallel, then safety is improved by detecting objects and imposing speed limits, but workability deteriorates due to conflicting speed limits hindering avoidance operations
Solution Approach 1:
The control execution unit acts as an intermediary that receives limit values from multiple control units (first and second control units) and resolves conflicts between them. It selectively executes the appropriate limit value based on the operational context, preventing conflicting speed limits from simultaneously restricting the vehicle. This mediator coordinate the multiple controls to work together harmoniously rather than contradictorily.
Solution Approach 2:
The system dynamically changes the vehicle speed limit parameter based on which control unit's conditions are met. When the first control unit's conditions are satisfied, its limit value is applied; when the second control unit's conditions are satisfied, its limit value is applied instead. This dynamic parameter adjustment ensures the appropriate speed limit is active for the current situation without conflict.
2Reliability
If a strict speed limit is imposed by secondary control to ensure safety, then collision prevention is improved, but avoidance operation capability deteriorates
Solution Approach 1:
The system dynamically adjusts which speed limit is applied based on real-time conditions. The control execution unit monitors whether the vehicle is in the process of avoiding an object and switches between the first control unit's limit value (which permits avoidance operations) and the second control unit's limit value (which ensures collision prevention) accordingly. This dynamic switching ensures both safety and operational capability are maintained.
Solution Approach 2:
The control execution unit preemptively prevents the harmful effect of conflicting speed limits by selecting the appropriate limit value before the conflict can hinder operations. When avoidance operations are detected, the system preemptively applies the first control unit's more permissive limit value, preventing the second control unit's strict limit from interfering with the avoidance maneuver.
Data Source
Figure 1~2
Figure 3~4
Figure 5~8
AI summary
A forklift (10) comprises a main control device (31), a travel motor (41), a travel control device (43), and an object detection unit (51). The travel control device (43) controls the travel motor (41). The object detection unit (51) detects the position of an object present in the reversing direction of the forklift (10). The main control device (31) sets a limit value according to a starting limit control. In the starting limit control, the limit value is set so that travel is permitted when it is determined that an operator is aware of the presence of an object. The main control device (31) sets the limit value according to an automatic deceleration control. The main control device (31) performs a speed limit according to the limit value if the limit value set according to the starting limit control is a limit value permitting travel.