How Transverse Sensitivity & Temperature Wreck Sensor Accuracy (And How to Fix It)

1. Impact of Transverse Sensitivity

Due to the inherent properties of piezoelectric materials and structural/manufacturing deviations in sensing elements, sensors inevitably generate output signals in response to transverse vibrations. This is quantified as the percentage ratio of transverse output to vertical-axis output.

• Compression-Type Sensors:
  • Theoretically prone to transverse output due to design.
  • Requires assembly adjustments for cancellation, but practical elimination is challenging.
  • High variability in transverse sensitivity (typically ±10–20%).
• Shear-Type Sensors:
  • Theoretically zero transverse output.
  • Actual transverse sensitivity arises from machining/assembly errors (typically ±3–5%).
• Bending Beam Sensors:
  • Intermediate transverse sensitivity between shear and compression types.

Conclusion: Shear designs outperform compression types in minimizing transverse sensitivity.

2. Temperature Effects on Sensing Elements

Temperature changes alter sensor output due to material properties:

• Material Comparison:
  • Quartz: Minimal temperature impact.
  • Synthetic Crystals: Higher temperature tolerance than quartz.
  • Piezoelectric Ceramics (most common in commercial sensors):
    • Output increases with rising temperatures.
    • Output decreases with falling temperatures (non-linear, larger deviations at low temps).
• Key Challenges:
  • Temperature response varies significantly across sensors, making correction via temperature coefficients impractical.
  • Manufacturing processes critically affect thermal behavior, even for identical materials (e.g., lead zirconate titanate).
• Structural Impact:
  • Differential thermal expansion between piezoelectric materials and metal components generates stress.
  • Compression/bending beam designs are prone to stress-induced false signals (critical in low-frequency measurements).

3. Impact of Base Strain Sensitivity

Sensor output can be affected by strain at the installation site. Base strain sensitivity depends on:

• Base stiffness
• Contact area with the test object
• Sensing element design
• Shear vs. Compression Designs:
  • Shear Sensors: Minimal contact area → Low base strain sensitivity.
  • Compression Sensors: Higher strain sensitivity due to direct force transmission.

Practical Takeaway: Shear-type sensors generally meet structural measurement needs without compromising frequency response.

About Dabey Technology: Precision in Every Axis

Since 2005, Dabey Technology has specialized in high-performance piezoelectric sensors for aerospace, industrial, and R&D applications. Our solutions address critical challenges like transverse sensitivity and thermal drift through:

• Advanced Designs: Patented shear-type MEMS sensors with <±3% transverse sensitivity.
• Robust Materials: Temperature-stable synthetic crystals (-55°C to 300°C).
• Certifications: ISO 9001, AS9100D, and IECEx/ATEX for hazardous environments.

Explore Our products:
→ Acceleration sensor