Debugging Angular Velocity in Absolute Encoders

Debugging Angular Velocity in Absolute Encoders  

During the design and debugging of an absolute encoder, an issue emerged: inaccurate angular velocity measurements. The process involves:  

1. **Angle Measurement**: Using absolute angle values as inputs.  

2. **Velocity Calculation Method**:  

   - A **cache queue** stores multiple historical angle values.  

   - Continuously updates the queue by enqueuing new angles and dequeuing old ones over time.  

   - Determines the **rotation direction** and detects **zero-crossing** (e.g., 0° to 360° transitions) based on the buffered data.  

**Advantages of This Approach**:  

- The angular velocity output cycle is **shorter than the sampling cycle**, improving temporal resolution.  

- Larger time spans in calculations reduce noise compared to direct two-point differentiation (e.g., using only consecutive angle values).  

**Identified Issues**:  

- **False Zero-Crossing Detection**: Occurs when boundary thresholds (e.g., near 0°/360°) are improperly set relative to the encoder's **full measurement range** (e.g., 360°).  

- Critical dependencies exist between **boundary truncation logic** and the encoder's physical range.  

**Next Steps**:  

- Refine boundary thresholds and validate against the encoder's measurement range.  

- Additional details will be provided after further testing and verification