As the primary feature and the focus of ThinGap’s product lineup, a lot has been spoken about zero cogging torque in the product lineup. Cogging torque is the interaction between the permanent magnets in the rotor, and the slots of the stator. Because the rotor magnets are attracted to the stator teeth, the torque required to move the rotor changes with the relative position of the rotor to the stator. In other words, additional energy is required to break the position dependent detent torque to advance the motor.

Cogging torque adds harmonic content to the torque-versus-angle curves for each phase. When driven by a sinusoidal current, harmonic content of the torque-versus-angle curves cause undesirable variations in torque production that interfere with smooth motor rotation. Additionally, phase imbalance common in a traditional slotted motor can further exacerbate the issue. The result is a phenomenon known as torque-ripple which is a variation of torque production with position.

There are a few issues when trying to integrate a traditional cogging motor into an application that requires precision actuation. To mitigate cogging torque in a slotted motor, it is possible to design the lamination stack with a rotational skew, so the magnetic field of the stator is diagonal to that of the magnetic field of the rotor. Alternatively, the magnets can be designed with a skew. Other techniques include using different slot-pole combinations and compensating for cogging and phase imbalance in the drive electronics.

However, when integrating slotted motors into systems for precision actuation, there will always be issues. Due to the nature of manufacturing, there is always variance between two seemingly identical motors, which can have an unpredictable impact on the cogging profile and phase balance. Furthermore, solutions to minimize cogging torque typically reduce the total output of the motor. The sunk cost of trying to mitigate cogging torque on both motor costs and development labor is better spent on the correct solution: slotless, coggless, brushless DC motors from ThinGap.

The benefit of ThinGap slotless and ironless motor designs is that they eliminate cogging torque by design. Their uniquely constructed phase windings produce a balanced phase amplitude and angle relationships between phases. This results in less than 1% total harmonic distortion of the back EMF waveform which minimizes torque ripple when paired with sinusoidal drive electronics.

ThinGap’s slotless motor architecture with wave-wound coils prevents cogging since the air-core rotor has no slots. Wound around a flat bobbin with a basket weave style winding, ThinGap’s composite air core motor kits have no iron. The thin nature of the coils produces very high copper packing and a motor with a large through hole, up to 80% of the outer diameter. In addition, ThinGap’s motor kits are available with Halbach array rotors, optimizing the magnetic flux for the highest torque density in a slotless motor.

To learn more about zero-cogging motion solutions, please contact us.

For many years, ThinGap motors have been successfully used in a variety of flywheel applications, ranging from gyro-stabilization in boats and satellites, to momentum storage for renewable energy. ThinGap’s TG Series of slotless motor kits are ideal for flywheel applications because of their highly efficient lightweight composite stator, optimal balance between torque and inertia, with negligible rotational losses, and zero cogging that is critical to achieving smooth motion at high speed.

Boats of all sizes stand to benefit from gyroscopic stabilization. Due to Newton’s third law of motion – every action carrying an equal and opposite reaction, a gyroscopes motion can be used to stabilize a ship or boat in heavy seas. A marine gyro-stabilizer is a large, spinning flywheel housed in the depths of the ship, near the keel. As the flywheel spins, computers on the bridge orient the flywheel against the ships current rolling motion, cancelling it out. ThinGap’s high efficiency motors make an excellent flywheel stabilizer of all sizes and can withstand harsh marine environments.

Another application where gyroscopic flywheels are used to change orientation is with satellites and their use of Reaction Wheel Assemblies. Yet another case of Newton’s Third Law, when a reaction wheel is spun up inside a satellite, the spacecraft turns in the opposite direction of the flywheel’s rotation, with this being used to steer and orient spacecraft in orbit. Because motion in space is multi-axial, each satellite carries multiple reaction wheels in an assembly to freely rotate. Since 2015, ThinGap has shipped thousands of kits for reaction wheel assemblies in large commercial and Government funded constellations, and in 2022, spun off their reaction wheel assembly motor kits to a separate product line.

An emerging use for highly efficient slotless motor kits is in momentum storage. Pioneered more than a decade ago for motorsports applications, excess or available energy is transferred to a motor that spins up a flywheel, whereby storing that energy in a rotating mass as a mechanical battery, instead of as chemical energy. Advantages of retaining the energy in a momentum flywheel application includes high power density compared with conventional batteries for quicker charge and discharge. Future applications of momentum storage could even extend to emerging markets such as renewable energy.

ThinGap’s ironless stator puts all the magnetics, the heaviest part of the motor, in the rotor. This maximizes the inertia for a given weight and size requirement, meaning the necessary flywheel mass can be reduced, and sometimes fully incorporated into the rotor, resulting in a lighter weight package for the same momentum storage capacity. Due to no iron saturation in the stator, ThinGap’s peak torque capacity is much higher for a similar weight motor, giving a dynamic response significantly better than the competition at a lighter weight.

To learn more about ThinGap’s TG Series of motor kits, click here.

Quick turn sample quantiles.  Industry leading lead-times.  On demand applications support. Standard, modified and custom options. ThinGap is the market leader in high performance, zero-cogging brushless DC motor kits and prides itself on the ability to rapidly react to both market demands and customer specific requirements.

Since 1999, ThinGap has developed over 100 motor designs, and shipped thousands of motors to a wide range of customers, from NASA to Fortune 500 companies, and even top Formula 1 teams. One of the key enabling factors is attributed to a tight integration of production, engineering, and operations at a single location in Camarillo, California.

ThinGap’s rapid reaction capabilities are reflected in sample quantity products often shipping within one week or less, a ramp to production volumes ship in 3-4 months, and preliminary custom designs and CAD available in 48 hours and custom design builds as soon as 12 weeks. Because of ThinGap’s advanced analytical modelling, final designs are usually within 95% of prediction performance. Well defined production processes, 3D printed tooling, refined modeling and analytical tools all contribute to the ability quickly support customers in a fast paced marketplace.

To learn more about ThinGap’s quick reaction production, click here.

ThinGap’s cogless motors have found success with novel and emerging applications due to their high efficiency, low-profile, smooth motion, and scalable architecture.

ThinGap’s zero-cogging, high performance motor kits are ideal for many aerospace and medical applications, such as gimbals, reaction wheel assemblies, and surgical robotics but are not limited to just these.  Demand has also come from unique market segments, where customers with emerging applications like energy storage, submersibles and advanced generators need ThinGap’s slotless motors. Slotless motors offer the benefits of smooth, cogless motion and high efficiency, with custom and modified features allowing for deep integration.

Flight simulation and human interface applications desire low hysteresis and pure haptic feedback capabilities.  Unmanned systems, whether airborne or underwater require high efficiency that equates to weight savings.  Starter-generators provide a dual function in UAV applications, with high cranking capability to start the engine, and then high efficiency with a clean signal output as a generator. Submergible systems can benefit from the rugged nature of slotless motors and their inherent ability to be fully encapsulated as part of their normal fabrication process. Flywheel applications, whether the well-established use of momentum storage in Reaction Wheel Assemblies (small satellite attitude control) or larger-scale ones used for gyro-stabilization or energy storage benefit from high-speed operation, and the maximum amount of inertia for a given weight.

Unmanned Underwater Vehicles

An emerging use for ThinGap’s brushless DC motors is in underwater propulsion. ThinGap motors are ideal for underwater direct drive propulsion because of a high torque-to-diameter ratio. With no gearbox, there’s no drivetrain losses, lower assembly weight, increased torque, and greater reliability. Ring architecture allows propulsion to be directly outside of the rotor (propeller), or inside (impeller).  High motor efficiency, low-noise underwater thrusters are ideal for the fast growing ROV, UUV, and AUV market segments.

Flight and Control Simulator Equipment

From aerospace to motorsports, simulation equipment is necessary to ensure immersion so professionals can hone their skills. ThinGap’s frameless architecture and smooth cogless motion makes it the ideal solution where a human operation or system need force sensing. Haptic systems require accurate torque feedback, without mechanical disturbances to improve the human control experience. ThinGap’s motor kits have near zero Eddy-current, low hysteresis, and a harmonic distortion of less than 1%, so torque output is directly proportional to current throughout the operating range.

Flywheel and Energy Storage

The air-core architecture’s inherent high speed operation with high efficiency is why ThinGap motors are ideal for both energy generation and storage. Scalable to large sizes and high speeds while maintaining a high power-to-weight ratio as well as weight optimized components yields highly specialized mass profiles. Targeted flywheel applications include Space-rated Reaction Wheel Assemblies, gyro-stabilization for large spacecraft and marine vessels, or novel methods to store and generate power as part of a clean energy strategy.

Starter/Generators

In both ground and airborne systems, as a starter-generator, ThinGap’s TG Series of air-core, impedance stators provide a stable, sinusoidal, low-droop voltage source and with an extremely high-power factor.  ThinGap motors are a pure three phase voltage output with less than 1% harmonic distortion. In addition, with a large aperture architecture, affording the kit a thin radial cross section, so a large through hole and very lightweight with system efficiency of up to 95%.

To learn more about ThinGap’s motor kits, click here.

With demand for electronics at an all-time high and a global supply shortage, the Semiconductor Equipment industry is busier than ever. Today’s modern wafer processing, automatic test and packaging system have a need for increased force density and high resolution move and hold steps. Highly precise, yet compact designs help enable inline process steps that are critical to higher throughput.

There are many needs for high precision BLDC electric motors in every stage of semiconductor production, from wafer processing all the way to inline testing. Motor selection is critical to system architecture, and factors in control methods, feedback requirements, and mechanical attributes.

Motors and actuators used for these applications are required to deliver cogless and absolute precision. Low profile motor architecture is ideal, because of the large internal aperture so optics or cabling can be routed through the middle. In addition to wafer positioning, precision motors are needed to direct optical systems, such as beam steering, with precision actuation to deliver precision to the micron level.

The continued use of Direct Drive solutions enables system-level advancements needed by semiconductor processing and test equipment.  Rapid and accurate movement defines the performance specifications.

Beyond zero cogging, ThinGap motor kits have near zero Eddy-current, low hysteresis, and a harmonic distortion of less than 1%, so torque output is directly proportional to current throughout the operating range. The resulting smooth motion, linear output, and low profile of ThinGap’s motor kits make them perfect for use in precision applications. Slotless motor kits with high torque, direct-drive capabilities are in many cases the ideal solution for semiconductor equipment.

ThinGap’s LS Series of slotless motor kits is an industry leader for applications requiring performance and efficiency. Standard LS motor kits range in size from 25 to 267 mm diameter and produce torque from 0.1 to 12.0 N-m continuous. With standard and modified configurations, the product line will cover voltages from 24-400 volts and current from 1 to 100 amps.

To learn more about the LS Series, click here.

With the fast and aggressive build out of Space, namely the rapidly growing number of LEO constellations orbiting Earth, comes the pervasive need for free-space optical communications that allows space-to-space, space-to-air and space-to-ground connections. Point-to-point use of highly collimated light in high-bandwidth communication is critical to the utility of “mesh networks” connecting each spacecraft with each other and to the ground.

Space-rated gimbals used for Satcom and Optical systems need high torque actuation that allows for decisive move-and-hold positioning and smooth motion for long-range target lock. With size and weight constraints being a design objective for spacecraft, a large aperture, low-profile is ideal for deep integration and desired performance. Zero cogging and high linear torque output inherently come with the slotless architecture.

Multi-axial gimbaling mechanisms, like those used in Coarse and Fine Pointing Assemblies can leverage the benefits of high performance Ring Motors to directly drive movement and maintain position. Frameless motor kits offer the further ability integrate the actuation function as part of optimized systems. Optimized systems offering Size, Weight and Power (SWaP) savings, which is highly desirable in any kind of spacecraft application.

Other Space-systems, like larger gimbal-based Control Moment Gyroscopes (CMG) are used for Attitude Control in larger satellites requiring greater quantities of torque and precision. In some cases, to quickly and precisely move in both azimuth and elevation, and in other cases, to quickly compensate for external “tumbling” disturbances common in orbit.

ThinGap’s LS Series of slotless motor kits is an industry leader for gimbal applications requiring high performance and efficiency. Using a proprietary design, thin wire-wrapped stators and optimized permanent-magnet rotors, ThinGap provides that can match the torque output of slotted motors while avoiding the cogging that plagues them.

ThinGap’s LS line of slotless motor kits range in size from 25 to 267 mm diameter and torque from .1 to 12 N-m continuous. With standard and modified configurations, the product line will cover voltages from 24-400 volts and current from 1 to 100 amps. Hall devices and special configurations are also available.

To learn more about the LS Series, click here.

ThinGap will be participating in the 37th Space Symposium in Colorado Springs on April 4-7, 2022. The company will be represented at the show by CEO, John Baumann, and Lead Applications Engineer, Matthew Panesis. Also present at the show will be members of ThinGap network of sales representatives. Besides meeting with existing and potentially new customers, domestic and international space agencies, and industry partners, a working unit of ThinGap’s H-LSI 75-12 turnkey Direct Drive Motor Assembly (image) based on the company’s slotless motor technology will be demonstrated at the ESI Motion booth (booth #612).

Matthew Panesis, ThinGap’s Applications Engineer commented on the event, “With the recent launch of our new TGR Series of Reaction Wheel Assembly motor kits, the timing is perfect to update our business partners, as well as customers about this new space-rated offering. In addition, we’re proud that our colleagues at ESI Motion will be demonstrating our Direct Drive Motor Assembly being driven by their control electronics.”

ThinGap slotless motors are widely used in many space applications, including Reaction Wheels, Control Moment Gyroscopes, Gimbals, Point-and-Track Satcom, Pumps and other precision actuation functions needed in spacecraft. For vacuum-compatible motor kits, ThinGap can easily provide variants of its commercial off-the-shelf motors. With these modifications, the motor kits can address the need for various program specifications, including low outgassing materials, specialty electronics, and in some cases, redundant stator windings to provide mission-critical assurance.

Space Symposium, held at The Broadmoor in Colorado Springs, Colorado, USA, has brought together space leaders from around the world to discuss, address and plan for the future of space since the inaugural event in 1984. In recent years, the Space Foundation team has welcomed more than 14,000 people from around the world, including speakers, attendees, exhibitors, volunteers, educators, and students. Space Symposium has become widely known as the premier U.S. space policy and program forum for information on and interaction among all sectors of space.

Small form-factor and high inertia-to-weight ratio ideal for microsatellites

Today’s Low Earth Orbit (LEO) satellites, including “SmallSat” and “CubeSat” microsatellites require a range of critical functions to serve their mission as cost-effective spacecraft. One of the most important functions is Attitude Control, which enables high accuracy pointing capabilities.

Reaction Wheel Assemblies (RWA) are used for multi-axis Attitude Control. RWAs use multiple motors that each spin at varying speeds creating a change in kinetic energy in the desired axes. RWAs utilize optimized rotating inertia, speed, and torque to accomplish this.
Motors used in RWAs need to have the optimal balance between torque and inertia, with negligible rotational losses and smooth motion performance. Zero cogging is critical to achieving this smooth motion. Additionally, parts must be made with low-outgassing materials, have flight heritage, and be sourced from suppliers that can support space programs’ stringent requirements.

ThinGap has tuned its product offering of “air core” motors to meet the demands of this application. This moving magnet air-core motor lends itself to very low drag at high operating speeds, and a wide speed range with constant torque. ThinGap’s ironless stator puts all the magnetics (the heaviest part of the motor) in the rotor, maximizing the inertia for a given weight and size requirement. The reaction wheel’s necessary flywheel mass can be reduced, and sometimes fully incorporated into the rotor. The resulting package is lighter weight for the same momentum storage capacity.

Smooth operation is achieved through a zero cogging slotless design that maintains sinusoidal torque versus angle curves with total harmonic distortion of less than 0.5%. The precision wound coil results in a phase-to-phase balance within 1%. Hands down, ThinGap has the highest precision RWA motors available, yielding pure torque vector control, with very low losses and zero cogging.

Motor sizes range from 25mm to 250mm in diameter and axial heights as small as 22 mm, with through holes up to 80% of the outside diameter. Since 2015, ThinGap has shipped thousands of Space-grade or MIL-STD rated motor parts for use in commercial satellites, military and commercial aircraft, and flight-grade NASA programs.

ThinGap Motors Used For RWA Applications

To learn more about the TGR Series of motor kits, click here.

The use of gimbals is becoming pervasive in Low-Earth-Orbit (LEO) Satellites and even ground-based systems. A heavy reliance on gimbal-based systems is an important part of the Defense Agencies’ critical Intelligence, Surveillance and Reconnaissance (ISR) objectives. In addition to defense, there are emerging uses in communications, and remote imaging applications.

Satellites use Gimbals for communication in a similar method for pointing and positioning, with the gimbals acting as the turret and gimbal unit alone, and a device called a fast-steering mirror delivering fine precision control that ensures a reliable optical data connection between satellites, either between low Earth orbit and geostationary satellites and between low Earth orbit satellites.

Multiaxial gimbals require high performance motors to directly drive their movements and to hold position. Advanced space-rated gimbal systems, like those used in Control Moment Gyroscopes (CMG), require a large amount of torque. In some cases, to move in both azimuth and elevation quickly and precisely, and in others to quickly compensate for external “tumbling” disturbances common in orbit.

One of the largest use-cases for ThinGap’s slotless motors are Gimbals, so much so that it considers itself to be the performance leader in Gimbal motors. From handheld applications for action cameras to large platforms designed for satellite-to-satellite communication, the applications of gimbals are endless. By using an array of different sensors and motors to counteract movement, electrically controlled gimbals serve to keep platforms stable and focused. Last summer, ThinGap delivered a series of motor kits to NASA for use in a space-based gimbal application, which serves as a testament to the quality and processes at ThinGap.

Using its proprietary design, thin wire-wrapped stators, and optimized permanent-magnet rotors, ThinGap provides motors with specifications that can match the torque output of slotted motors while avoiding the cogging that plagues them. Ring motors are the perfect form factor for gimbals with their round shape, direct drive mounting capability and empty center.

ThinGap’s motor kits offer a large through hole, usually 65% of more of the device’s outer diameter (OD), due to its efficient mechanical design and optimized components. ThinGap’s LS line of slotless motor kits range in size from 25 to 267 mm diameter and torque from 0.1 to 12 N-m continuous. With standard and modified configurations, the product line will cover voltages from 24-400 volts and current from 1 to 100 amps. Hall devices and special configurations are also available.

To learn more about the LS Series, click here.

ThinGap has made available two new Space-rated frameless motor kits specifically designed for Reaction Wheel Assemblies (RWA) used to control small and miniaturized satellites. The new TGR 29-12 and TGR 45-20 are an extension of the widely used TG Series of aerospace motors supplied by ThinGap for nearly two decades.  The vacuum compatible parts are 29mm and 45mm wide, and 12mm and 20mm tall, respectively.

ThinGap’s patented motor architecture has inherent advantages in RWA and flywheel applications: an efficient ironless core, zero cogging stator, high torque capacity, dynamic responsiveness, and overall weight savings.

The “air core” architecture lends itself to very low drag at high operating speeds and cogless torque. The wave-wound design of the stator produces a sinusoidal Back-EMF with total harmonic distortion of less than 1%. The precision hand wound coil results in a phase-to-phase balance within 1 degree. In combination, these produce the highest precision RWA motors available which yields essentially pure torque vector control with very low losses and zero cogging.

The new TGR’s design puts all the magnetics (the heaviest part of the motor) in the rotor, maximizing the inertia for a given weight and size. The resulting package is lighter weight for the same momentum storage capacity, and because of no iron saturation in the stator, ThinGap’s peak torque capacity is much higher than a similar weight motor. This gives a high dynamic response significantly better than the competition at a lighter weight. The motors are also highly efficient (up to 95%) since the architecture lends itself to very low drag at high operating speeds.

The TGR 29-12’s offers a continuous torque of 0.012 N-m and 0.0054 N-m/√W motor constant. The TGR 45-20 offers a continuous torque of 0.075 N-m and 0.0197 N-m/√W motor constant. This allows the new TGR motor kits to offer more than double the torque of the closest competitor with minimal losses.

Prior TG Series models have been widely used in RWA systems. Sample quantities of the new TGR 29-12 and TGR 45-20 are available with a 12 week lead time.  Additional models of the TGR Series will include a 79 mm and 61 mm OD part set to be released later in 2022.

To learn more, click here.