Tri-axial Force Balanced Accelerometer

Brief Description

Force Balanced Accelerometer (FBA) sensor is a spring mass device using variable capacitance transduction and electromagnetic feedback. The output is fed back to the torque coil, which is an integral part of the mass. From the coil, the feedback loop is completed through feedback resisters. The acceleration sensitivity is controlled by the gain of the post amplifier. Aluminum pivot support blocks are used to maintain long-term drift free stability of the accelerometer mass. The tri-axial FBA has three accelerometers orthogonally mounted on an internal deck plate. Each of these units are housed inside the water proof, anodized cast aluminum housing and sealed to prevent ingree dirt and moisture.

Salient Features

• Highly sensitive, low frequency seismic sensor.
  
• Excellent measurement stability.
  
• Rugged construction and high reliability.
  
• Full scale Range ±1.0g.
  
• Natural frequency- 50Hz.
  
• Dynamic range- 130dB.
  
• Linearity less than 1% of full scale.
  
• Cross axis sensitivity less than 0.03g/g.
  
• Normal damping-70% critical.
  
• Noise less than ±2.5µV.
  

Applications

• Monitoring earthquakes.
  
• Strong motion recording.
  
• Monitoring structural vibrations.
  
• Monitoring vibrations in aerospace.
  
• Suitable for various commercial applications.
  

Benefits

Developed technology can be used for finding the building codes for vital buildings by measuring the structural response. The designed sensor will be used to record strong motion data (Peak Ground Acceleration) for different applications including Seismic Alert System.

Contact:

Central Scientific Instruments Organisation,
Chandigarh
Website: http://www.csio.res.in/