Robotic Arm Path Planning with Real-Time Position Compensation

Solution Overview

Problem

Existing array-based pick-and-place processes with robotic arms suffer from error accumulation and limited operational range due to inadequate sensing and compensation mechanisms, leading to incomplete tasks and high costs.

Innovation Solution

A path planning method involving origin calibration, real-time sensing of X-axis and Y-axis displacements using position sensors, and continuous feedback and compensation to calculate and correct coordinate errors, allowing the robotic arm to perform multiple pick-and-place jobs accurately.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a spring sensor is used to detect overtravel and send alert signals, then the robotic arm can be protected from excessive movement, but the robotic arm stops operation and cannot complete the array-based pick-and-place process

Engineering Contradiction:

Improveovertravel protectionVSAvoidcompletion of pick-and-place process

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent implements a feedback mechanism where position sensors continuously monitor the robotic arm's actual position during pick-and-place operations. The controller receives real-time position data, compares it with the theoretical position, calculates coordinate errors, and performs dynamic compensation. This closed-loop feedback system eliminates error accumulation while enabling the robotic arm to complete the entire array-based pick-and-place process without premature stopping.

Inventive Principle:

Principle #23Feedback

2Measurement precision

If multiple force sensors are used to sense gas pressure for gripper alignment, then alignment precision can be improved, but the cost increases significantly

Engineering Contradiction:

Improvegripper alignment precisionVSAvoidnumber of sensors required

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical sensing systems with a simplified electromagnetic sensing approach. Instead of using multiple force sensors to detect gas pressure, the system employs position sensors to directly detect the robotic arm's position in space. The controller then calculates coordinate errors and performs compensation through software algorithms, eliminating the need for expensive mechanical force sensors while maintaining high measurement precision.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If the robotic arm operates without continuous position compensation, then the system structure remains simple, but error accumulation limits the operational range

Engineering Contradiction:

Improvesystem structureVSAvoidoperational range

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent implements a feedback mechanism where position sensors continuously monitor the robotic arm's actual position during pick-and-place operations. The controller receives real-time position data, compares it with the theoretical position, calculates coordinate errors, and performs dynamic compensation. This closed-loop feedback system eliminates error accumulation while enabling the robotic arm to complete the entire array-based pick-and-place process without premature stopping.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent dynamically adjusts the position parameters of the robotic arm through coordinate error compensation. By continuously calculating the difference between actual and theoretical positions and applying correction values, the system extends its effective operational range without requiring a fundamentally more complex physical structure. The compensation is achieved through parameter modification in the control system rather than structural changes.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS9833906B2Method of path planning for array-based pick-and-place performed with robotic arm and compensator for use with the method

Publication Date: 2017.12.05 HIWIN TECH CORP

AI summary

A method of path planning for array-based pick-and-place performed with a robotic arm is characterized in that: during each instance of the pick-and-place process performed with the robotic arm, an X-axis position sensor and a Y-axis position sensor sense coordinate errors of a pick-and-place point such that a controller calculates a position compensation value according to the sum of vectors of the coordinate errors, corrects the pick-and-place position of the robotic arm according to the position compensation value, and generates the coordinates of the next pick-and-place point. By repeating the aforesaid process flow, it is feasible to perform plenty array-based pick-and-place jobs.