There are a number of different types of sensors which can be used as essential components in numerous designs for machine olfaction systems. Electronic Nose (or eNose) sensors fall into five categories, conductivity sensors, piezoelectric sensors, Metal Oxide Field Effect Transistors (MOSFETs), optical sensors, and these employing spectrometry-based sensing methods.
Conductivity sensors may be made from metal oxide and polymer elements, each of which exhibit a change in resistance when exposed to Volatile Organic Compounds (VOCs). In this particular report only Metal Oxide Semi-conductor (MOS), Load Sensor and Quartz Crystal Microbalance (QCM) is going to be examined, since they are well researched, documented and established as important element for various machine olfaction devices. The application, where proposed device will likely be trained to analyse, will greatly influence deciding on a sensor.
A torque sensor, torque transducer or torque meter is really a device for measuring and recording the torque on the rotating system, such as an engine, crankshaft, gearbox, transmission, rotor, a bicycle crank or cap torque tester. Static torque is comparatively easy to measure. Dynamic torque, on the contrary, is difficult to measure, as it generally requires transfer of some effect (electric, hydraulic or magnetic) through the shaft being measured to your static system.
One way to achieve this is to condition the shaft or perhaps a member linked to the shaft with a series of permanent magnetic domains. The magnetic characteristics of such domains will be different in accordance with the applied torque, and so can be measured using non-contact sensors. Such magnetoelastic torque sensors are typically used for in-vehicle applications on racecars, automobiles, aircraft, and hovercraft.
Commonly, torque sensors or torque transducers use strain gauges put on a rotating shaft or axle. With this particular method, a means to power the strain gauge bridge is necessary, and also a means to receive the signal from your rotating shaft. This is often accomplished using slip rings, wireless telemetry, or rotary transformers. Newer kinds of torque transducers add conditioning electronics as well as an A/D converter towards the rotating shaft. Stator electronics then look at the digital signals and convert those signals to Miniature Load Cell, such as /-10VDC.
A more recent development is the use of SAW devices linked to the shaft and remotely interrogated. The force on these tiny devices because the shaft flexes can be read remotely and output without the need for attached electronics on the shaft. The probable first use in volume will be in the automotive field as, of May 2009, Schott announced it has a SAW sensor package viable for in vehicle uses.
A different way to measure torque is by way of twist angle measurement or phase shift measurement, whereby the angle of twist resulting from applied torque is measured by utilizing two angular position sensors and measuring the phase angle between them. This procedure can be used inside the Allison T56 turboprop engine.
Finally, (as described in the abstract for US Patent 5257535), if the mechanical system involves the right angle gearbox, then the axial reaction force experienced by the inputting shaft/pinion can be linked to the torque felt by the output shaft(s). The axial input stress must first be calibrated from the output torque. The input stress can easily be measured via strain gauge measurement of the input pinion bearing housing. The output torque is readily measured utilizing a static torque meter.
The torque sensor can function just like a mechanical fuse and is also a vital component to have accurate measurements. However, improper setting up the torque sensor can harm the device permanently, costing time and money. Hence, cdtgnt torque sensor must be properly installed to make certain better performance and longevity.
The performance and longevity from the torque sensor as well as its reading accuracy will likely be affected by the appearance of the Force Sensor. The shaft becomes unstable on the critical speed of the driveline to result in torsional vibration, which can harm the torque sensor. It is required to direct the strain for an exact point for accurate torque measurement. This point is typically the weakest reason for the sensor structure. Hence, the torque sensor is purposely designed to be one of many weaker components of the driveline.