In the world of Embedded Motor Diagnostics, the quality of your data determines the accuracy of your health monitoring system. Raw sensor data from accelerometers or current sensors is often noisy and inconsistent. To bridge this gap, applying Signal Normalization techniques is essential.
Why Signal Normalization Matters
When monitoring motors at the edge, signals can vary significantly due to different operating speeds or sensor sensitivities. Normalization ensures that the input data resides within a specific range (usually 0 to 1 or -1 to 1), making it easier for Machine Learning models or threshold-based algorithms to detect anomalies like bearing wear or misalignment.
Key Techniques for Embedded Systems
- Min-Max Scaling: Best for bounded data where the minimum and maximum values are known.
- Z-Score Standardization: Useful when the signal follows a Gaussian distribution, centering the data around a mean of zero.
- Decimal Scaling: A computationally light method suitable for low-power microcontrollers.
Implementation Example: Min-Max Normalization in C++
Below is a snippet of how you can implement a simple normalization function for an embedded motor diagnostic tool using Arduino or ESP32.
// Min-Max Normalization Function
float normalizeSignal(float input, float minVal, float maxVal) {
if (maxVal == minVal) return 0.0; // Prevent division by zero
// Formula: (x - min) / (max - min)
float normalized = (input - minVal) / (maxVal - minVal);
// Constrain the result between 0 and 1
return constrain(normalized, 0.0, 1.0);
}
void loop() {
float rawVibration = analogRead(A0);
float cleanSignal = normalizeSignal(rawVibration, 0, 1023);
// Proceed with Fault Detection Logic
Serial.println(cleanSignal);
}
Optimizing for Edge Performance
To maintain real-time diagnostics, it is recommended to use fixed-point arithmetic if your microcontroller lacks an FPU (Floating Point Unit). This reduces latency and power consumption, which is critical for continuous motor health monitoring.
Conclusion
Applying signal normalization is not just a preprocessing step; it is a foundation for reliable Embedded Motor Diagnostics. By scaling your data correctly, you ensure that your diagnostic system remains robust across different hardware and environmental conditions.
Embedded Systems, Motor Diagnostics, Signal Processing, Edge AI, Predictive Maintenance, Signal Normalization, Arduino, ESP32