Swinging Drive Control Using Motor Back-EMF Detection Without Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing automatic swings and rocking chairs or glider chairs require costly sensors for swinging frequency and phase tracking, as well as amplitude control, leading to high costs.
Innovation Solution
A swinging drive control apparatus using a controller and motor that detects counter-electromotive force to control the motor's operation, eliminating the need for sensors by adjusting PWM pulse duty factors and driving times based on detected counter-electromotive force values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensors are used to implement swinging frequency and phase tracking as well as amplitude control, then control precision is improved, but device complexity and cost increase
Solution Approach 1:
The motor serves itself by using its own counter-electromotive force signal for feedback control. The controller detects the counter-electromotive force generated during motor operation and uses this signal to determine swinging state and adjust driving parameters, eliminating the need for external sensors.
Solution Approach 2:
The counter-electromotive force detection serves multiple functions simultaneously: it provides feedback for frequency and phase tracking, amplitude control, and swinging state determination. One detection mechanism achieves what would traditionally require multiple separate sensors.
2Measurement precision
If sensors are used to implement swinging frequency and phase tracking as well as amplitude control, then control precision is improved, but cost increases
Solution Approach 1:
The motor serves itself by using its own counter-electromotive force signal for feedback control. The controller detects the counter-electromotive force generated during motor operation and uses this signal to determine swinging state and adjust driving parameters, eliminating the need for external sensors.
Solution Approach 2:
The counter-electromotive force detection serves multiple functions simultaneously: it provides feedback for frequency and phase tracking, amplitude control, and swinging state determination. One detection mechanism achieves what would traditionally require multiple separate sensors.
3Measurement precision
If sensors are used to implement swinging frequency and phase tracking as well as amplitude control, then control precision is improved, but cost increases
Solution Approach 1:
The motor serves itself by using its own counter-electromotive force signal for feedback control. The controller detects the counter-electromotive force generated during motor operation and uses this signal to determine swinging state and adjust driving parameters, eliminating the need for external sensors.
Solution Approach 2:
The counter-electromotive force detection serves multiple functions simultaneously: it provides feedback for frequency and phase tracking, amplitude control, and swinging state determination. One detection mechanism achieves what would traditionally require multiple separate sensors.
4Device complexity
If counter-electromotive force detection is used instead of sensors, then device complexity is reduced, but measurement capability must be maintained
Solution Approach 1:
The patent replaces mechanical or optical sensing systems with an electrical detection method. By measuring the counter-electromotive force (an electrical parameter) generated during motor operation, the system infers mechanical swinging state parameters such as position, velocity, and acceleration without physical contact or external sensors.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables effective swinging frequency and phase tracking, as well as amplitude control without sensors, simplifying the control system and reducing costs while maintaining comfort and resonance.
Implementation Method 1
the controller detects a counter-electromotive force of the motor and drives the motor according to the detection result
Implementation Method 2
generally use motors to drive swinging objects to swing
Data Source
AI summary
Disclosed is a swinging drive control apparatus, including a controller and a motor, where the controller detects a counter-electromotive force of the motor and drives the motor according to the detection result. Also disclosed is a corresponding method, including: measuring a counter-electromotive force of a motor in a previous cycle; and comparing a maximum counter-electromotive force value with a preset value, and calculating a PWM pulse duty factor in a next cycle. By directly detecting the counter-electromotive force of the motor without using a sensor, the present invention implements swinging frequency and phase tracking as well as swinging amplitude control, and simplifies a control system.