There are a number of different types of sensors which can be used as essential components in various designs for machine olfaction systems. Electronic Nose (or eNose) sensors belong to five categories, conductivity sensors, piezoelectric sensors, Metal Oxide Field Effect Transistors (MOSFETs), optical sensors, and these employing spectrometry-based sensing methods.
Conductivity sensors could be made up of metal oxide and polymer elements, each of which exhibit a modification of resistance when in contact with Volatile Organic Compounds (VOCs). In this particular report only Metal Oxide Semi-conductor (MOS), Load Cell and Quartz Crystal Microbalance (QCM) will be examined, because they are well researched, documented and established as vital element for various types of machine olfaction devices. The applying, where the proposed device will likely be trained on 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, like an engine, crankshaft, gearbox, transmission, rotor, a bicycle crank or cap torque tester. Static torque is fairly simple to measure. Dynamic torque, on the contrary, is difficult to measure, since it generally requires transfer of some effect (electric, hydraulic or magnetic) from your shaft being measured to your static system.
A good way to achieve this would be to condition the shaft or perhaps a member connected to the shaft with a series of permanent magnetic domains. The magnetic characteristics of those domains will vary according to the applied torque, and thus may 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 placed on a rotating shaft or axle. Using this method, a method to power the strain gauge bridge is necessary, and also a means to get the signal through the rotating shaft. This is often accomplished using slip rings, wireless telemetry, or rotary transformers. Newer varieties 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 Micro Load Cell, such as /-10VDC.
A far more recent development is the usage of SAW devices linked to the shaft and remotely interrogated. The strain on these tiny devices as the shaft flexes may be read remotely and output without resorting to attached electronics on the shaft. The probable first utilization in volume will be in the automotive field as, of May 2009, Schott announced it possesses a SAW sensor package viable for in vehicle uses.
Another way to measure torque is by means of twist angle measurement or phase shift measurement, whereby the angle of twist caused by applied torque is measured by using two angular position sensors and measuring the phase angle between the two. This procedure is utilized in the Allison T56 turboprop engine.
Finally, (as described inside the abstract for US Patent 5257535), if the mechanical system involves a right angle gearbox, then your axial reaction force felt by the inputting shaft/pinion can be related 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 be simply measured via strain gauge measurement in the input pinion bearing housing. The output torque is readily measured using a static torque meter.
The torque sensor can function just like a mechanical fuse and it is a key component to have accurate measurements. However, improper installing of the torque sensor can harm the device permanently, costing time and money. Hence, cdtgnt torque sensor has to be properly installed to make sure better performance and longevity.
The performance and longevity in the torque sensor as well as its reading accuracy is going to be affected by the design of the Tension Compression Load Cell. The shaft becomes unstable at the critical speed in the driveline and causes torsional vibration, which can harm the torque sensor. It is actually essential to direct the strain to an exact point for accurate torque measurement. This point is typically the weakest point of the sensor structure. Hence, the torque sensor is purposely made to be among the weaker components of the driveline.