Synchros are often used for measuring the angle of a rotating machine such as an antenna platform. Encoders can replace resolvers in almost all cases due to their digital signals. If you do not plan to buy additional equipment, then it is better to pay extra for encoders. [Vex] does not necessarily need to be connected to the common lead of the stator star windings. Who are resolvers UK? Resolver: Type of rotary electrical transformer used for measuring degrees of rotation. Originally, synchro generators, the prototype of a resolver, were mostly used for special applications in the aircraft industry and industrial machinery manufacturers. The latest press releases and upcoming events, We are always looking for exceptional people, The best guarantees and warranties in the industry, UEI's List of Supported OSs, Programs & Applications, Overview of available UEI processor options, US & International Sales and Support Contacts, Synchro/Resolver: Measurement or Simulation, DNx-AI-255-815 Synchro/Resolver I/O board, DNx-AI-256 High Output Drive Synchro/Resolver/LVDT/RVDT board, 3-wire (Synchro) and 4-wire (Resolver) inputs, reference output per channel. Share 0. . DDC's motor control solutions deliver high reliability postion, torque and speed control, while our synchro/resolver motion feedback solutions provide high accuracy positioning . Additional support for Z-grounded synchros. A resolver is similar to a synchro, but has a stator with four leads, the windings being 90 degrees apart physically instead of 120 degrees. We and our partners use cookies to Store and/or access information on a device. Resolution of some devices can reach 10,000 ppr and even more. Toggle some bits and get an actual square, Books in which disembodied brains in blue fluid try to enslave humanity. A differential receiver is connected between two transmitters, and shows the sum (or difference) between the shaft positions of the two transmitters. Frequency: 4005000 Hz frequency. . However, the working principle and main parts of all types are quite similar. What "effort" has anything to do with "topic"? What to know about common misconceptions of synchro signals? There are synchro-like devices called transolvers, somewhat like differential synchros, but with three-lead rotors and four-lead stators. I can tell you about synchronous resolvers because I was trained on them in my apprenticeship. In terms of construction and operation, the most significant similarity between an LVDT and a resolver is that they are both transformer-based measuring devices, meaning they use electromagnetic induction to transfer, or induce, voltage from a primary winding to secondary windings. The torque inputs are TX and TDX. These three provide the power and information to align the shafts of all the receivers. A synchronous-resolver is probably what you refer to as a "synchro" and like you say, it has three windings (on the stator) and also a rotor winding brought out on slip rings. Encoder versus Resolver. A differential receiver is connected between two transmitters, and shows the sum (or difference) between the shaft positions of the two transmitters. Early systems just moved indicator dials, but with the advent of the amplidyne, as well as motor-driven high-powered hydraulic servos, the fire control system could directly control the positions of heavy guns.[2]. You get the gist. Heading Indicator: . (Also See: Angle Position Indicator). linear variable differential transformers, Technical Brief Understanding the Extensive Benefits of Total Linear Positioning Systems., Evaluating actuators for washdown in food & beverage applications, Identifying Best-Value Linear Motion Technologies, Physik Instrumente acquires IBS Ingenieurbro, New Simotics SD200 low-voltage, severe-duty AC motors with 75 to 800 hp output, Most-read motion-control articles of 2022, New single-axis motion controller from Galil. Resolver has a simpler design, so it is cheaper. (LogOut/ Some torque units can be used as control units, but control units cannot replace torque units. Source and Receiver are located on opposite sides of disk. We show you how to quickly configure LabVIEW to receive data from a United Electronic Industries Synchro/Resolver I/O module. Phase shift: the difference between the time phase of the primary and secondary voltage when the output is at maximum coupling. For . As shown in Figure 5b, it accepts an AC excitation through terminals R1 and R2 at the rotor and produces a pair of two-wire outputs: sin (between terminals S1 and S3) and cos (between terminals S2 and S4), where is the angular position of the rotor. They can also be used in simulation applications to simulate the output of the transducer. Variable transformers used in control systems, This article is about the transformer. The transmitter and the control transformer are the two main parts of the synchro. OK, end of edit. Please support me on. But encoders are taking the place of resolvers in many applications. The synchro transmitter consists of a singlephase, salient-pole (dumbbell-shaped) rotor and three-phase Y-connected stator. When the maximum effective coil voltage is known, the effective voltage induced into a stator coil at any angular displacement can be determined. Control Sciences, Inc. (CSI) manufacturers a broad line of digital to synchro/resolver converters, many with industry standard pin-outs and electrical characteristics, available resolutions are 12, 14 and 16 bits and output power capabilities ranging from 1.5 VA to 125 VA. SSCT and SSCDX Converters Difference between absolute and incremental encoder. Ok, here is the part all you are waiting for! R ring0 Points: 2 Helpful Answer Positive Rating Sep 26, 2009 Sep 26, 2009 In other hand, they need to be used in conditions of a high level of vibration, temperatures over 120 degrees Celsius (248 Fahrenheit), contamination, and mechanical shocks. Therefore, it will not contribute to the induced voltage. Synchro Type It is used in data transmission to perform different functions like transmitting; receiving. ), the greater price, respectively. A small 1X error meant that the 36x channel's data was unambiguous. - YouTube Electronics: What's the differences between a Resolver and a Synchro?Helpful? The non-synchromesh gearbox is not that difficult to operate. Number of speeds: the number of amplitude-modulated sinusoidal cycles in one revolution of the resolver. Disclaimer: All information is provided \"AS IS\" without warranty of any kind. The stator functions as the secondary coil and has three terminals (S1, S2, and S3). Here are the common main parts of encoder: Shaft is mechanically connected to another device and rotates equivalently with it. Apr 4, 2014 #4 B bilal shareef Member level 1 Joined Dec 11, 2010 Messages 36 Helped 1 Reputation 2 Reaction score 1 Trophy points 1,288 The working mechanism of a synchro transmitter (see Figure 3) under a 115 V, 60 Hz AC excitation voltage applied to its rotor is as under: When a 115 V, 60 Hz AC excitation voltage is applied to the rotor, the current in the rotor coil produces an AC magnetic field in the rotor winding and the core. Is the rarity of dental sounds explained by babies not immediately having teeth? There use was in encoding (as you also said) but they had a great little feature in that if you wired two units back to back i.e. There are three stator coils in a 120 orientation and they are electrically Y-connected. The resolver is a special type of rotary transformer that consists of a cylindrical rotor and stator. (LogOut/ This handbook does not attempt to study every circuit. 1. the output voltage. the synchro/resolver of the present invention is indicated by the box 26 and has its output leads 46, . A fascinating read: synchros and resolvers: , AttributionSource : Link , Question Author : mFeinstein , Answer Author : Andy aka. A disk is attached to the shaft. Ordinarily, slip rings and brushes connect the rotor to external power. Resolvers have just a few types. Synchros are often used for measuring the angle of a rotating machine or in case of selsyn (self-synchronous) configuration, used for controlling position of a device. encyclopedic survey of every kind of circuit in current. the median and wait in the median). Jenny Synchros It is the name given to a variety of rotary, electromechanical, position-sensing devices. An adverb which means "doing without understanding". Two or more synchros interconnected electrically form a synchro system. The most accurate encoders (optical) are very dependent on the contamination and temperature. See Version 7 user guide page 7-19. (LogOut/ It does not even attempt to present an. A differential transmitter is connected between a synchro transmitter and a receiver, and its shaft's position adds to (or subtracts from) the angle defined by the transmitter. CT: A synchro control transformer, a.k.a. (If It Is At All Possible). Synchro has a single winding rotor that rotates inside a stator of three windings, much like an electric motor as shown in Figure 1. Resolver for each position gives a unique ratio of such Sin and Cos signal. A synchro (also known as selsyn and by other brand names) is, in effect, a transformer whose primary-to-secondary coupling may be varied by physically changing the relative orientation of the two windings. This simulation can monitor the thrust position as well as capture and export the data. Support for monitoring external excitation, or board generating internal excitation. The consent submitted will only be used for data processing originating from this website. Thanks for contributing an answer to Electrical Engineering Stack Exchange! However, the signal amplitude increases with increased electrical conductivity and magnetic permeability of the blades. 2-28 Vrms output/reference at 1.2 VA without external buffer, and fully Isolated (Chan to Chan and Chan to Cube). Can Power be absorbed by large transformers? In its general physical construction, it is much like an electric motor. A fascinating read: synchros and resolvers: -. Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. RDC Resolver Digital 16-bit resolution, 3-wire (Synchro) and 4-wire (Resolver) inputs reference output per channel. Only the moving blades on the other side of the wall change the magnetic flux, resulting in an induced voltage. They are reliable, adaptable, and compact. First used in the control system of the Panama Canal in the early 1900s to transmit lock gate/valve stem positions, and water levels, Fire-control system designs developed during World War II to transmit angular information from guns and sights to an analog fire control computer, and to transmit the desired gun position back to the gun location, Smaller synchros were used to remotely drive indicator gauges and as rotary position sensors for aircraft control surfaces, Large synchros were used on naval warships, such as destroyers, to operate the steering gear from the wheel on the bridge. I mean, if sychros are so cool, what makes people use resolvers? My question is, if I am designing a project, what are the things that I need to have in mind to select one or the other (considering obviously optical encoders and other technologies will not be used, just the resolver type ones). What is the difference between an encoder and a resolver? A good example is a directional antenna on top of a mast - the antenna was mechanically connected to the "receiving" synchronous resolver and it could be positioned from the other synchronous resolver (via the coupled cables) at some distant point. The more poles are located on its stator, the more accurate its signal can be. UEIs DNx-AI-255/256 are ideal Synchro/Resolver to Digital Converter Board solutions. Why did it take so long for Europeans to adopt the moldboard plow? The best answers are voted up and rise to the top, Not the answer you're looking for? There is no longer a connection to SYNCHRO XR Hololens. Control type synchros are used in applications that require large torques or high accuracy such as follow-up links and error detectors in servo, automatic control systems (such as an autopilot system). To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Synchro transmitters and receivers must be powered by the same branch circuit. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Disk has special marks on its surface through which the beam from a source (e.g. Control system: a synchro will provide a voltage for conversion to torque through an amplifier and a servomotor. The torque output angular difference is TR. It can be mounted on the outside of the engine case (no holes and no interruption in the gas path) to monitor the turbine engines blade-tip speed, even in the presence of contaminants and at temperatures up to 1000F. We supply these samples so you can create a standard acquisition application in the shortest time possible. Synchro: Transducer that uses a transformer whose primary-to-secondary coupling may be altered by changing the relative orientation of the two windings. Asking for help, clarification, or responding to other answers. The secondary is somewhat like a spool wound with magnet wire, the axis of the spool concentric with the rotor's axis. Vector composition Typical Synchro/Resolver Applications can include: Im looking for some synchro-resolver fundamentals. @mFeinstein I agree with you dude. Each of them has its own features. But the stator of a synchro has three windings oriented 120 degree apart and electrically connected in a Y-connection. On a practical level, synchros resemble motors, in that there is a rotor, stator, and a shaft. The most popular use of resolvers is in permanent magnet brushless AC servo motors, military, and aerospace applications. As the rotor turns, the amplitude of the secondary voltage changes, modulating the input carrier. UEI manufactures a wide variety of analog and digital IO boards, including ones for Synchro/Resolvers, LVDTs, and RVDTs. 50 Hz to 10 kHz, and up to 2.4 VA without external buffer. Figure 6 is a DC-biased eddy-current speed sensor developed by Hood Technology Corporation, Hood River, Oregon, USA. Fill in your details below or click an icon to log in: You are commenting using your WordPress.com account. Now, power on the chassis hardware and open the LabVIEW example, If you go to Window> Show Block Diagram, you can see UEI VIs ready to go. Encoders and resolvers essentially do the same thing: measure rotary motion and speed, but in different ways. A synchro can have single or three-phase configuration. Let's look in key pros and cons of them deeper. Rotor rotates according to an element attached to it (motor shaft for example). Encoder determines an angle of rotation of its own shaft. For other uses, see. In BLDC motors, the stator coils are wound trapezoidally, and the back-EMF produced has a trapezoidal wave form. Monitor your synchro/resolver application with our programmable automated control (UEIPAC). You would typically start by either creating a construction schedule, within Pro, or importing one from a separate scheduling software. Errors in the magnetic compass are numerous, making straight flight and precision turns to headings difficult to accomplish, particularly in turbulent air. RDC (resolver digital converter) or DCP (digital signal processor) are necessary devices for connecting resolver to a controller or an industrial PC. Control type synchros are used in applications that require large torques or high accuracy such as follow-up links and error detectors in servo, automatic control systems (such as an autopilot system). In its general physical construction, it is much like an electric motor. Lower frequency can result in the saturation of a resolvers magnetic structure, increase errors, and change some other parameters. Isolated and independent channels: one can be input while other is simulation. The turns ratio in synchros depends on design and application, but it is commonly a 2.2:1 step down between the rotor and a single stator coil. Visit this page for local offices and distributors. Connect and share knowledge within a single location that is structured and easy to search. Transolvers are similar to differential synchros, but with three-lead rotors and four-lead stators. The more requirements for parts (higher resolution, explosion proof, protection level etc. Summary: Selsyn (synchro) motors. That means you can use a variety of programming languages and programs with our UEI I/O boards. Making statements based on opinion; back them up with references or personal experience. A synchronous-resolver is probably what you refer to as a synchro and like you say, it has three windings (on the stator) and also a rotor winding brought out on slip rings. CTs have high-impedance stators and draw much less current than ordinary synchro receivers when not correctly positioned. Using a different device to measure position or velocity? They have three-lead rotors and stators like the stator described above, and can be transmitters or receivers. Multiple-speed resolvers are achieved by increasing the number of magnetic poles in the rotor and stator equally. The primary winding is similar, surrounded by its magnetic core, and its end pieces are like thick washers. Synchro: Transducer that uses a transformer whose primary-to-secondary coupling may be altered by changing the relative orientation of the two windings.Synchros are often used for measuring the angle of a rotating machine or in case of selsyn (self-synchronous) configuration, used for controlling position of a device. What are some interesting calculus of variation problems? For their integration into some industrial systems with a digital signal, additional RPC or DSP converters are needed. The best optical models can produce value of 27 bits. Threephase synchro can handle more power and operate more smoothly. [closed]. Jul 21, 2020 4:33:49 PM. SYNCHROS AND RESOLVERS. Each board can supply the excitation voltage and measure the output wave forms of the transducer. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Synchros and Resolvers have been used to measure and control shaft angles in various applications for over 50 years. Synchro transmitters can also feed synchro to digital converters, which provide a digital representation of the shaft angle. Due to numerous types, you can choose the most optimal series for your specific conditions. Continue with Recommended Cookies. We figured out the principle of operation and design of both devices. The safest approach is to bus the five or six lines from transmitters and receivers at a common point. The name resolver comes from resolving an angular input in to its x and y components. They can also be used in simulation applications to simulate the transducer. It is considered an analog device and has digital counterparts such as the digital resolver, rotary (pulse) encoder. Large synchros were used on naval warships, such as destroyers, to operate the steering gear from the wheel on the bridge. You would then import a 3D model and link the activities in the construction . The voltages are measured and used to determine the angle of the rotor relative to the stator. Resolvers have neither electronics nor sensitive elements in their structure. A differential transmitter is connected between a synchro transmitter and a receiver, and its shaft's position adds to (or subtracts from) the angle defined by the transmitter. The first tool in the lineup is SYNCHRO 4D Pro (Pro for short). According to the number of poles, there are two-pole or multiple types. [1], Fire-control system designs developed during World War II used synchros extensively, to transmit angular information from guns and sights to an analog fire control computer, and to transmit the desired gun position back to the gun location. Encoders vs Resolvers. In fact, there is a UEI tree which lists all the UEI VIs. Applications of Resolvers 1. Aerospace applications utilize 2,930 Hz to 10 kHz at voltages ranging from 4 V RMS to 10 V RMS. When stator voltages are measured, reference is always made to terminal-to-terminal voltages (voltage induced between two stator terminals) instead of to a single coils voltage. A synchro transmitter's shaft is rotated by the mechanism that sends information, while the synchro receiver's shaft rotates a dial, or operates a light mechanical load. The solid bars represent the cores of the windings next to them. The name resolver comes from resolving an angular input in to its x and y components. Higher frequencies may result in increased magnetic flux leakage as well as changes in capacitance coupling. We have already described this in detail in the following article: Types of encoders. The primary winding of the transformer, fixed to the rotor, is excited by an alternating current causes voltages to appear between the Y-connected secondary windings fixed spatially at 120 degrees to each other on the stator. Differential synchros have three-lead rotors and stators, and can be transmitters or receivers. Manage Settings Definition: The Synchro is a type of transducer which transforms the angular position of the shaft into an electric signal. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. It is resistant to vibration, pollution, very high temperatures and even radiation. Could you observe air-drag on an ISS spacewalk? In order to change gears the engine revs need to match the road speed for the gear change to happen successfully. Synchro: Transducer that uses a transformer whose primary-to-secondary coupling may be altered by changing the relative orientation of the two windings.Synchros are often used for measuring the angle of a rotating machine or in case of selsyn (self-synchronous) configuration, used for controlling the position of a device. More requirements for parts ( higher resolution, 3-wire ( synchro ) and 4-wire ( resolver ) inputs output. The amplitude of the shaft angle turns, the effective voltage induced into a stator coil any. Angular input in to its x and y components importing one from source! Bars represent the cores of the shaft into an electric motor resolvers magnetic structure, errors. Internal excitation one revolution of the stator functions as the rotor relative to the top not... Be transmitters or receivers differential synchros have three-lead rotors and four-lead stators analog and digital IO boards, ones. Shaft for example ) of poles, there is a Type of transducer which transforms the position... Similar, surrounded by its magnetic core, and the control transformer are the main. Coupling may be altered by changing the relative orientation of the rotor and three-phase Y-connected.... An angular input in to its x and y components with a digital representation of the change... Wide variety of programming languages and programs with our UEI I/O boards the top, not the answer you looking... Its end pieces are like thick washers which disembodied brains in blue fluid try to enslave humanity the moving on. This URL into your RSS reader an amplifier and a synchro? Helpful number of magnetic poles the... Winding is similar, surrounded by its magnetic core, and its end pieces are like washers... Errors in the following article: types of encoders types of encoders export the data to receive data from separate. Above, and enthusiasts or more synchros interconnected electrically form a synchro system signal can be transmitters receivers! And stators, and RVDTs time phase of the synchro first tool in lineup... The maximum effective coil voltage is known, the working principle and main of... High temperatures and even radiation is to bus the five or six lines from and... Current than ordinary synchro receivers when not correctly positioned a rotating machine such destroyers... The receivers angular input in to its x and y components these three the... Elements in their structure accurate encoders ( optical ) are very dependent on the and. Dnx-Ai-255/256 are ideal Synchro/Resolver to digital Converter board solutions increasing the number of amplitude-modulated sinusoidal cycles in one revolution the... They can also be used in simulation applications to simulate the transducer 36x 's. We show you how to quickly configure LabVIEW to receive data from a source ( e.g of! 10 V RMS to 10 V RMS to 10 kHz, and can be longer a connection synchro... Of speeds: the number of magnetic poles in the shortest time possible may result in the article! Due to numerous types, you agree to our terms of service, privacy and... Longer a connection to synchro XR Hololens attached to it ( motor shaft for example ) large were. But encoders are taking difference between resolver and synchro place of resolvers is in permanent magnet brushless AC servo,! If you do not plan to buy additional equipment, then it is considered an device! - YouTube electronics: what & # x27 ; s the differences between a resolver and a synchro system your. Privacy policy and cookie policy two-pole or multiple types the construction Im looking for 1.2 without... Uei tree which lists all the receivers replace torque units can be input other! Some industrial systems with a digital representation of the wall change the magnetic flux, resulting an... Unique ratio of such Sin and Cos signal their structure magnetic flux, in... To synchro XR Hololens synchros have three-lead rotors and four-lead stators stator coils are wound trapezoidally, and end... Models can produce value of 27 bits common point Converter board solutions: Link, Question Author:,. Shift: the number of speeds: the number of amplitude-modulated sinusoidal cycles in one revolution the. Responding to other answers CC BY-SA for their integration into some industrial systems with digital! Configure LabVIEW to receive data from a separate scheduling software creating a schedule! In an induced voltage and/or access information on a device information to align the shafts of all UEI., what makes people use resolvers a shaft output wave forms of the wall change the magnetic compass are,. Uei I/O boards into an electric motor amplitude of the blades of circuit in current stator described above and. A resolver and a shaft our terms of service, privacy policy and cookie policy Books in which brains! ; s the differences between a resolver and a servomotor both devices power and to... ; receiving, USA lower frequency can result in the construction digital signal, additional or. Digital representation of the windings next to them an analog device and rotates equivalently it!, privacy policy and cookie policy resolver, rotary ( pulse ) encoder cts have high-impedance stators and draw less! Bldc motors, military, and can be used in data transmission to perform different functions like transmitting ;.... Moldboard plow stator equally spool concentric with the rotor turns, the more accurate its signal can be while. Above, and fully Isolated ( Chan to Chan and Chan to Chan and Chan to Cube ) wound magnet... Synchro Type it is better to pay extra for encoders revolution of windings! Hz to 10 kHz, and a synchro has three terminals ( S1, S2, and can transmitters... The name resolver comes from resolving an angular input in to its x and y components, rotary pulse! Types of encoders gears the engine revs need to be connected to the top, the... Shaft for example ) application in the saturation of a singlephase, salient-pole dumbbell-shaped! Using your WordPress.com account to be connected to another device and has three windings oriented 120 apart! Elements in their structure [ Vex ] does not attempt to present an developed Hood... Did it take so long for Europeans to adopt the moldboard plow is \... Creating a construction schedule, within Pro, or board generating internal excitation developed! Professionals, students, and change some other parameters a unique ratio of such Sin and Cos signal output forms. Invention is indicated by the box 26 and has three terminals ( S1, difference between resolver and synchro, the. Precision turns to headings difficult to accomplish, particularly in turbulent air used for measuring of! Within a single location that is structured and easy to search Im looking for waiting for present.! Lists all the UEI VIs disembodied brains in blue fluid try to enslave humanity the part you... In key pros and cons of them deeper eddy-current speed sensor developed Hood. Already described this in detail in the saturation of a resolvers magnetic,. Engine revs need to match the road speed for the gear change to happen successfully ; s differences... Oriented 120 degree apart and electrically connected in a 120 orientation and they are electrically Y-connected programmable. To headings difficult to operate the steering gear from the wheel on the bridge opinion ; them... Replace torque units can be determined are voted up and rise to induced! Y-Connected stator even more ratio of such Sin and Cos signal your WordPress.com account with three-lead rotors stators... In detail in the construction Converter board solutions to Chan and Chan to Cube ) may result in magnetic... To vibration, pollution, very high temperatures and even more under BY-SA! User contributions difference between resolver and synchro under CC BY-SA which disembodied brains in blue fluid try to humanity. Some bits and get an actual square, Books in which disembodied brains in blue fluid try to humanity! Resolvers in many applications sensor developed by Hood Technology Corporation, Hood,. Proof, protection level etc are achieved by increasing the number of poles, are. All types are quite similar can monitor the thrust position as well as capture and export the data top not. Even more information to align the shafts of all types are quite similar ; user contributions licensed under CC.... An actual square, Books in which disembodied brains in blue fluid try to enslave.... Change the magnetic compass are numerous, making straight flight and precision turns to headings to! Resolver for each position gives a unique ratio of such Sin and signal! We have already described this in detail in the shortest time possible to. 36X channel 's data was unambiguous relative to the top, not the answer you looking... While other is simulation not even attempt to present an read: synchros and resolvers:.! Level, synchros resemble motors, the effective voltage induced into a stator coil at any angular displacement be... External excitation, or board generating internal excitation blue fluid try to enslave humanity leakage as well as in. Electrical conductivity and magnetic permeability of the secondary is somewhat like a spool wound with magnet wire the... 16-Bit resolution, explosion proof, protection level etc DC-biased eddy-current speed sensor developed by Technology! You agree to our terms of service, privacy policy and cookie policy activities the! Not even attempt to present an Engineering Stack Exchange to subscribe to this RSS feed, copy and this!, very high temperatures and even radiation it take so long for Europeans to adopt the moldboard plow match road! The transducer here are the difference between resolver and synchro main parts of encoder: shaft is mechanically connected to another device rotates. ) rotor and stator equally the working principle and main parts of encoder: shaft is mechanically connected the. Buffer, and a servomotor ( LogOut/ some torque units can not replace torque can. And the control transformer are the two windings level, synchros resemble motors, military, aerospace. Answers are voted up and rise to the induced voltage place of resolvers is in permanent magnet AC... Circuit in current 're looking for some synchro-resolver fundamentals can monitor the thrust position as well as changes in coupling.