Table 7. accelerometer application
Accelerometer product
Industrial application ACH-01-XX ACH-04-08-01 ACH-04-08-07/08 ACH-04-08-05
Spaceflight and
Defense electronic anti jamming sensor X X X X
Monitor X
Model analysis of X X X X
Front air bag
Please consult the manufacturer for the multi axis airbag accelerometer information
Side balloon
Anti-theft X X X X
Skid / rain sensor X X
Computer and
Peripheral component disk drive vibration sensor X X
Computer mouse sensor X
Virtual reality sensor X
Home appliance imbalance sensor X X X
Spray arm blocking sensor X X X
Microwave acoustic sensor X X
Vibration switch X X
Consumer electronics loudspeaker feedback X for other options consult manufacturers
X pickup
Security X X X
State monitoring of industrial machinery X X X
Bearing monitor X X X
Instrument and
Active vibration damping X X for measuring equipment
Vibration switch X X
Preventive maintenance of X X X
Medical sports sensor X X X
Please consult the manufacturer for further information on the pacemaker
Seismic circuit breakage X of power station
Machine monitoring X X X
Telecom GPS system X X
Vibration switch X X
Transport and material transport monitoring X X
Railway system X X
Ultrasonic application
The wide frequency response and physical properties of the piezoelectric film polymerized structure make it a choice for some medical explorer and nondestructive testing. In addition, thin film sensors are also being applied to ultrasonic induction devices, such as air ranging ultrasonic ranging for measuring distance, fluid level sensor and flow rate measuring instrument using Doppler speed shift of sound velocity proportional to fluid flow.
Medical imaging ultrasound
Piezoelectric ceramic materials are used for medical imaging sensors because of their high sensitivity and wide band. The d33 constant, the strain produced by the added voltage is one order of magnitude higher than the piezoelectric polymer. One drawback of piezoelectric ceramics is that the sound impedance is high, about 30Mrayls (1Mrayl=106kg/m2s), and the human tissue is about 1.5Mrayls. This impedance mismatch can be compensated by the 1/4 wavelength matching layer, but this will result in ultrasonic pulse attenuation due to the bonding layer and connection method. The acoustic impedance of piezoelectric thin films is about 4Mrayls, which is much better. In addition, piezoelectric devices with very small demand for high-frequency applications, ceramics are too brittle, and cannot be machined into desired geometries.
Intrusive images require a device that has a lower power than an external probe. The higher frequency of the intrusive catheter greatly improves the resolution of the image. A medical imaging company has developed an invasive imaging probe using a piezoelectric film for the treatment of prostate laser catheters (Figure 61). The piezoelectric thin film sensor is about 30 microns thick and is located near the end of the catheter. The frequency of the probe is more than 7MHz, and the new catheter can greatly improve the success rate of prostate surgery, and less pain and loss of blood than the present method.
The body guided phased array imaging devices using a piezoelectric polymer film have been made by researchers at the Duke University for the first time. A unit array consisting of 32 1mmx0.56mm units is connected to a circuit that matches well with a well - optimized sensor and has been tested. Results, when the working frequency is 2.5MHz, the sensitivity is lower than that of PZT sensor.
|