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 could be composed of 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) will be examined, since they are well researched, documented and established as essential element for various types of machine olfaction devices. The application, in which the proposed device will likely be trained on to analyse, will greatly influence the option of sensor.
A torque sensor, torque transducer or torque meter is actually a device for measuring and recording the torque on a 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 other hand, is difficult to measure, because it generally requires transfer of some effect (electric, hydraulic or magnetic) from your shaft being measured to some static system.
One way to accomplish this is always to condition the shaft or a member connected to the shaft with a series of permanent magnetic domains. The magnetic characteristics of such domains can vary according to the applied torque, and so could 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 important, and also a methods to have the signal from the rotating shaft. This can be accomplished using slip rings, wireless telemetry, or rotary transformers. Newer types of torque transducers add conditioning electronics as well as an A/D converter towards the rotating shaft. Stator electronics then read the digital signals and convert those signals to Miniature Load Cell, like /-10VDC.
A far more recent development is the usage of SAW devices linked to the shaft and remotely interrogated. The force on these tiny devices because the shaft flexes could be read remotely and output without making use of attached electronics on the shaft. The probable first utilization in volume are usually in the automotive field as, of May 2009, Schott announced it has a SAW sensor package viable for in vehicle uses.
An additional way to measure torque is by means 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 the two. This procedure is utilized within the Allison T56 turboprop engine.
Finally, (as described within the abstract for US Patent 5257535), if the mechanical system involves a right angle gearbox, then your axial reaction force gone through by the inputting shaft/pinion can be linked to the torque gone through by the output shaft(s). The axial input stress must first be calibrated from the output torque. The input stress can be easily measured via strain gauge measurement of the input pinion bearing housing. The output torque is easily measured employing a static torque meter.
The torque sensor can function just like a mechanical fuse and is an important component to get accurate measurements. However, improper installing of the torque sensor can harm the device permanently, costing time and money. Hence, cdtgnt torque sensor needs to 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 be afflicted with the appearance of the Force Transducer. The shaft becomes unstable on the critical speed of the driveline and causes torsional vibration, which can damage the torque sensor. It is necessary to direct the strain to an exact point for accurate torque measurement. This aspect is typically the weakest reason for the sensor structure. Hence, the torque sensor is purposely made to be one of many weaker components of the driveline.