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 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 might be made up of metal oxide and polymer elements, each of which exhibit a change in resistance when subjected to Volatile Organic Compounds (VOCs). Within this report only Metal Oxide Semi-conductor (MOS), Load Sensor and Quartz Crystal Microbalance (QCM) is going to be examined, because they are well researched, documented and established as important element for various machine olfaction devices. The application form, where the proposed device will be trained on to analyse, will greatly influence the option of sensor.
A torque sensor, torque transducer or torque meter is a device for measuring and recording the torque on the rotating system, including an engine, crankshaft, gearbox, transmission, rotor, a bicycle crank or cap torque tester. Static torque is relatively simple to measure. Dynamic torque, on the other hand, 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 make this happen is always to condition the shaft or even a member connected to the shaft with a series of permanent magnetic domains. The magnetic characteristics of these domains will be different in accordance with the applied torque, and therefore can be measured using non-contact sensors. Such magnetoelastic torque sensors are usually employed 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. Using this method, a method to power the strain gauge bridge is essential, in addition to a methods to have the signal from the rotating shaft. This is often accomplished using slip rings, wireless telemetry, or rotary transformers. Newer types of torque transducers add conditioning electronics and an A/D converter for the rotating shaft. Stator electronics then browse the digital signals and convert those signals to Micro Load Cell, like /-10VDC.
A much more recent development is the usage of SAW devices connected to the shaft and remotely interrogated. The stress on these tiny devices since the shaft flexes can be read remotely and output without resorting to attached electronics on the shaft. The probable first use within volume are usually in the automotive field as, of May 2009, Schott announced it features a SAW sensor package viable for in vehicle uses.
An additional way to measure torque is by way of twist angle measurement or phase shift measurement, whereby the angle of twist as a result of applied torque is measured by using two angular position sensors and measuring the phase angle between the two. This procedure can be used within the Allison T56 turboprop engine.
Finally, (as described within the abstract for US Patent 5257535), in the event the mechanical system involves the right angle gearbox, then this axial reaction force gone through by the inputting shaft/pinion can be associated with the torque experienced by the output shaft(s). The axial input stress must first be calibrated against the output torque. The input stress can be easily measured via strain gauge measurement in the input pinion bearing housing. The output torque is definitely measured employing a static torque meter.
The torque sensor can function just like a mechanical fuse and it is a vital component to get accurate measurements. However, improper installation of the torque sensor can harm the device permanently, costing money and time. Hence, cdtgnt torque sensor must be properly installed to make sure better performance and longevity.
The performance and longevity of the torque sensor and its reading accuracy will likely be affected by the style of the Force Sensor. The shaft becomes unstable on the critical speed in the driveline to result in torsional vibration, which can damage the torque sensor. It is required to direct the strain with an exact point for accurate torque measurement. This point is usually the weakest reason for the sensor structure. Hence, the torque sensor is purposely made to be among the weaker components of the driveline.