The class of mechanical sensors includes a fairly large number of different sensors based on many principles, but the four groups of general sensors discussed here - force sensors, accelerometers, pressure sensors, and gyroscopes - cover most of the principles involved in the sensing of mechanical quantities either directly or indirectly. Some of these sensors are used for applications that initially do not seem to relate to mechanical quantities. For example, it is possible to measure temperature through the expansion of gases in a volume. The expansion can be sensed through the use of a strain gauge, which is a classical mechanical sensor. In this application an indirect use of a strain sensor is made to measure temperature. On the other hand, some mechanical sensors do not involve motion or force. An example of this is the optical fiber gyroscope, which will be discussed later in this chapter.

Chapter Contents:

• 6.1 Introduction
• 6.2 Some Definitions and Units 282 Contents
• 6.3 Force Sensors
• 6.3.1 Strain Gauges
• 6.3.2 Semiconductor Strain Gauges
• 6.3.2.1 Application
• 6.3.2.2 Errors
• 6.3.3 Other Strain Gauges
• 6.3.4 Force and Tactile Sensors
• 6.4 Accelerometers
• 6.4.1 Capacitive Accelerometers
• 6.4.2 Strain Gauge Accelerometers
• 6.4.3 Magnetic Accelerometers
• 6.4.4 Other Accelerometers
• 6.5 Pressure Sensors
• 6.5.1 Mechanical Pressure Sensors
• 6.5.2 Piezoresistive Pressure Sensors
• 6.5.3 Capacitive Pressure Sensors
• 6.5.4 Magnetic Pressure Sensors
• 6.6 Velocity Sensing
• 6.7 Inertial Sensors: Gyroscopes
• 6.7.1 Mechanical or Rotor Gyroscopes
• 6.7.2 Optical Gyroscopes
• 6.8 Problems

Inspec keywords: temperature measurement; strain gauges; accelerometers; fibre optic gyroscopes; pressure sensors; strain sensors; actuators; force sensors

Other keywords: accelerometers; mechanical sensors; actuators; strain gauge; strain sensor; force sensors; pressure sensors; optical fiber gyroscope; temperature measurement

Subjects: Fibre optic sensors; Mechanical variables measurement; Thermometry; Fibre optic sensors; fibre gyros; Measurement of mechanical variables; Velocity, acceleration and rotation measurement; Thermal variables measurement; Pressure measurement; Pressure and vacuum measurement; Sensing and detecting devices; Velocity, acceleration and rotation measurement; Mechanical instruments, equipment, and techniques