Thumb Bucket Payload Calculation with Task-Based COG Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Construction machines with thumb buckets face challenges in accurately determining payload when tasks of grabbing and scooping are performed in random order, as the center of gravity position varies based on the task type.
Innovation Solution
A work machine equipped with a bucket and a pivotally coupled thumb, along with processing circuitry, determines the current task based on the bucket's angle and calculates payload using the center of gravity position, automatically switching the COG position to ensure accurate payload determination regardless of task order.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the work machine performs both grabbing and scooping tasks with a thumb bucket, then the machine's versatility is improved, but the accuracy of payload determination deteriorates when tasks are performed in random order
Solution Approach 1:
The system dynamically switches between grabbing mode and scooping mode based on real-time detection of task type. The payload determination method is adaptively changed according to the detected task, allowing the system to maintain high measurement precision while supporting multiple task types. The processing circuitry detects whether the thumb bucket is performing grabbing or scooping and automatically selects the appropriate calculation method.
2Device complexity
If the system uses a fixed center of gravity position for payload calculation, then the calculation method is simple, but the payload determination accuracy deteriorates when task type varies
Solution Approach 1:
The system employs dynamic selection of center of gravity positions based on the detected task type. When grabbing mode is detected, the first center of gravity position is used; when scooping mode is detected, the second center of gravity position is used. This dynamic adaptation ensures accurate payload determination without requiring a single complex calculation method for all scenarios.
Solution Approach 2:
The system changes the parameter of center of gravity position according to the task type. By switching between different center of gravity positions (first COG for grabbing, second COG for scooping), the system adapts the calculation parameters to match the actual physical configuration, thereby maintaining high measurement precision across different tasks.
3Measurement precision
If the system automatically switches center of gravity position based on task detection, then the payload determination accuracy is improved, but the system complexity increases
Solution Approach 1:
The system performs self-service by automatically detecting the task type and autonomously selecting the appropriate center of gravity position without requiring manual intervention. The processing circuitry self-determines whether grabbing or scooping is being performed and automatically adjusts the calculation parameters, reducing the need for complex external control systems while maintaining high accuracy.
Solution Approach 2:
The system implements a feedback mechanism where the detected task type (grabbing or scooping) feeds back into the payload calculation process. Based on this feedback, the system automatically selects the appropriate center of gravity position, creating a closed-loop system that maintains accuracy while keeping the control logic relatively simple through conditional branching.
Data Source
AI summary
A work machine comprises a bucket attached to an end of a stick of the work machine as a work tool, a thumb pivotally coupled to the end of the stick, and processing circuitry. The processing circuitry is configured to determine a current task of the work machine among scooping an object by the bucket or grabbing the object by the bucket and the thumb, based on an angle of the bucket, and calculate payload with a parameter of a center of gravity position of the payload based on the determined current task.