Hybrid Feedback Signal Control for Material Testing Systems
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Solution Overview
Problem
High-frequency resonances and phase delay in feedback signals from sensors used in material testing systems, such as those employing linear electromagnetic motors, can disrupt the control of the motor operation, impacting the accuracy and stability of material characterization.
Innovation Solution
A hybrid feedback signal is generated by combining low-pass and high-pass filtered signals, with the final control signal processed to reduce resonances and phase delay, allowing for improved system stability and accuracy in load application systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the sensor feedback signal is used directly to control the motor operation, then the system can maintain simple control structure, but high-frequency resonances and phase delay will disrupt the control stability and accuracy
Solution Approach 1:
The feedback signal is segmented into different frequency components using a filter mechanism with a first filter (low-pass) and a second filter (high-pass). This segmentation allows the system to process different frequency ranges separately, eliminating the harmful high-frequency resonances and phase delays while maintaining the useful low-frequency control information, thus improving control stability without significantly increasing overall system complexity.
2Speed
If high-frequency components are preserved in the feedback signal, then the system bandwidth is maintained, but resonances and phase delay negatively impact motor control accuracy
Solution Approach 1:
Different frequency components of the feedback signal are treated with different quality characteristics through selective filtering. The low-frequency components are preserved with minimal modification for accurate control, while the high-frequency components are filtered to remove resonances and phase delays. This local differentiation of signal treatment maintains necessary bandwidth for system responsiveness while ensuring high precision in material characterization by eliminating harmful high-frequency distortions.
Data Source
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AI summary
[0026] A method of controlling a system using a hybrid feedback signal includes providing an input signal with a predetermined waveform to the system and measuring an output of the system with a sensor. An output signal of the sensor is used in a first frequency band as a first portion of a feedback signal. A simulated signal is created in a second frequency band that has one or more of substantially reduced (i) resonances, (ii) phase delay and (iii) noise when compared to the output signal of the sensor in the second frequency band. The simulated signal is used in the second frequency band as a second portion of the feedback signal.