Fast sensorless collision detection for resource-constrained pmsm controllers using an FFRLS-based method.
Duo Zhao1, Thai Ren2, Ganke Huang2
1School of Integrated Circuits Science and Engineering, Southwest Jiaotong University, Chengdu, 610000, China. zhaoduo@swjtu.edu.cn.
Scientific Reports
|March 10, 2026
Summary
This study introduces a fast, low-complexity sensorless collision detection method for permanent magnet synchronous motors (PMSMs). It uses a specialized estimator to monitor load torque changes, enabling quick and reliable collision detection in embedded systems.
Area of Science:
- Electrical Engineering
- Control Systems
- Robotics
Background:
- Collision detection is crucial for protecting machinery and ensuring safety in automated systems.
- Existing methods often require complex computations or external sensors, limiting their use in resource-constrained environments.
- Permanent-magnet synchronous motors (PMSMs) are widely used in industrial applications, necessitating efficient collision detection solutions.
Purpose of the Study:
- To develop a low-complexity, fast, and sensorless collision detection algorithm for PMSMs.
- To enable reliable collision detection in embedded controllers with limited computational resources.
- To achieve rapid detection of collisions under various operating conditions.
Main Methods:
- Utilizing a forgetting-factor recursive least-squares (FFRLS) estimator to estimate load torque from motor motion equations.
- Monitoring abrupt changes in a processed load-torque metric for collision event identification.
- Designing the algorithm to avoid high-order matrix operations and external sensor integration.
Main Results:
- The proposed method demonstrated fast and repeatable collision detection performance.
- Experimental validation confirmed effectiveness under constant speed, acceleration, and time-varying load conditions.
- The algorithm achieved a practical balance between computational cost and detection reliability.
Conclusions:
- The FFRLS-based sensorless collision detection method offers an effective solution for PMSMs.
- The approach is well-suited for resource-constrained embedded motor drives.
- This technique enhances the safety and robustness of automated systems utilizing PMSMs.
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