Showcasing ThinGap’s highly adaptable technology, the TGD 129-114 introduces carbon fiber components for the most extreme TG Series part set ever made.

Designed for the high-power and high-speed required in UAV and other Airborne applications.

ThinGap has completed its latest high-power motor-generator prototype, the TGD 129-114, in support of a Government-funded defense program. In generator mode, the new assembly is designed for a steady 10 kW of power output at 7,000 RPM and is capable of 45 kW at 20,000 RPM. Mechanically, the TGD 129-114 has an outer diameter (OD) of 134 mm (5.28 in.), and an axial height of 124 mm (4.91 in.), making it about the same size as a coffee can.

Developed for use by the United States Army in airborne applications, namely Class II unmanned aerial vehicles (UAVs), the TGD 129-114 is the most radical evolution of the ThinGap TG Series to date. Designed for the extremely high continuous speed requirements typical in airborne generator applications, as well as being strength and weight optimized. Previous TG Series part sets have been used as starter-generators in other UAV platforms.

To minimize unit weight and maximize rotor inertia, the new assembly uses carbon fiber reinforced polymer (CFRP) for both the inner and outer sleeves that retrain the rotor’s magnets and are joined together by a purposely designed metallic top cap with fan blades that forces airflow across the stator. First developed in the late 1950s, CFRPs have become ubiquitous in demanding, high-performance applications such as aerospace and motorsports to reduce weight while not sacrificing strength.

The TGD 129-114 demonstrates ThinGap’s ability to deliver tailor-made high-power solutions. With more than two decades of experience in the design and production of slotless motor kits, ThinGap leverages its proven designs and analytical modeling that results in highly accurate transitions from predicted performance to real world operation. Furthermore, the process steps needed to produce motors of all sizes are highly scalable, and ThinGap has shipped large class motors with up to 400 kW of output power.

Designed for Reaction Wheel Assemblies (RWA) and Flywheel Applications

Optimized for maximum inertia, giving the greatest momentum for the least amount of mass

Specifically built for use in vacuum, making it space compatible by design 

ThinGap has delivered to a commercial customer its latest purpose-built reaction wheel motor kit, the TGR 60-30. This newest motor kit has an outer diameter (OD) of 60 mm and an axial height of just 29.6 mm, providing a continuous in-vacuum torque output of 0.08 N-m, and a peak torque of 1.61 N-m. A complete datasheet is available on ThinGap’s website.

With a total part mass of 273 grams, the TGR 60-30 fits between the already released TGR 89-26 and TGR 29-12, showcasing the Company’s highly scalable stator architecture. In addition, the rotor of the TGR 60-30 is optimized for maximum inertia, giving the motor the greatest momentum for the least mass. As part of the industry’s first clean-sheet reaction wheel assembly product line, the TGR Series is designed for Attitude Control in SmallSat applications and other high precision systems.

Prior TG Series models have been widely used in Reaction Wheel Assemblies (RWA), due to the patented architecture’s inherent advantages when used in flywheel applications. Because of the efficient, lightweight ironless core, zero-cogging stator, and high power-to-weight ratio, the TGR 60-30 offers more than double the torque of the closest competitor with minimal losses and no radial forces between the stator and rotor.

With more than two decades of experience in the design and production of slotless motor kits, ThinGap can leverage proven designs and analytical modeling that results in highly accurate transitions from predicted performance to real world operation. Furthermore, the process steps needed to produce motors of all sizes is highly scalable; ThinGap has shipped motors from 25 mm up to 600 mm in size.

Scheduled to launch early in the morning on February 6, 2024 from Kennedy Space Center aboard a SpaceX Falcon 9 rocket, the PACE Mission marks the first time ThinGap has achieved flight certification by NASA. PACE is a NASA mission that ThinGap has been proud to support. Developed and produced by NASA Goddard Space Flight Center in Maryland, PACE is a planned decade-long mission to study the Earth’s oceans and atmosphere.

The PACE launch is scheduled for 1:35 a.m. EST.  In attendance to witness the historic event firsthand will be representatives from ThinGap’s management and engineering teams.  In 2021, ThinGap supplied custom made LS Series motor kits to the development team at NASA Goddard.  These motors were designed to be integrated into the PACE Mission’s Ocean Color Instrument or OCI sensor payload.

The goal of the PACE mission is the monitoring of worldwide oceanic health through observation of the color of the ocean’s surface, as well as how reflected sunlight interacts with the atmosphere. The color of surface water is heavily influenced by sunlight’s interaction with chlorophyll, a green pigment found in plants as well as the phytoplankton that inhabit the ocean. Designed and built by NASA Goddard, the heart of the OCI (Ocean Color Instrument) is an advanced hyperspectral optical spectrometer, capable of measuring the color of the ocean from ultraviolet, through visible color, to short-wave infrared wavelengths. Previous NASA satellites have been limited to studying a small portion of this spectrum, so a single instrument being able to capture more data than before is a huge benefit to researchers. ThinGap supplied custom LS Series motors to NASA in 2021 that drive the continuously rotating cross-track telescope.

The two other payloads aboard PACE are polarimeters intended to measure how sunlight reflected by the Earth’s surface interacts with clouds, aerosols, and the ocean surface. The first is SPEXone, designed and built by a Dutch team including Airbus Defense & Space, Netherlands Institute for Space Research, and supported by the Netherlands Organization for Applied Scientific Research is designed to characterize particles suspended in the atmosphere by chemical composition and their impacts on climate change.

The other polarimeter aboard PACE, designed and built by University of Maryland Baltimore County’s Earth and Space Institute is HARP2 (Hyper-Angular Rainbow Polarimeter) sensor. HARP2 is a wide-angle imaging polarimeter designed to measure the properties of atmospheric particles, including their size, distribution, shape, and density. Previous HARP instruments have been flown on both airborne platforms as well as CubeSats, which helped influence the design of HARP2.

ThinGap is honored to support this mission by supplying custom motors, as well as achieving flight certification. Additionally, ThinGap has supplied more than 2,500 motor kits in support of a major commercial constellation, as well as US Space Force projects for prime customers.

Seventy percent of the Earth’s surface is covered in water. Whether for defense, industry or exploration, the demand of underwater systems, such as manned submersibles, Remotely Operated Vehicles (ROVs), and Unmanned Underwater Vehicles (UUVs) is a market that is expected to grow to more than $10 billion by the 2030s, according to Emergen Research.  These underwater platforms of all forms stand to leverage the benefits of ThinGap’s high efficiency motor kits. With critical functions such as robotic actuation and quiet, yet highly efficient propulsion, ThinGap’s motors continue to find a home in marine and subsea applications.

An emerging use for ThinGap’s brushless DC motors is marine propulsion. ThinGap motors are ideal for underwater direct drive thrusters because of a high torque-to-diameter ratio. ThinGap recently delivered a floodable motor assembly based off its LS Series to a defense customer for a UUV application. With no gearbox, there are no drivetrain losses, enabling lower assembly weight, increased torque, and greater reliability.

As a flooded motor, ThinGap’s stator has the added benefit of inherent cooling from the cold seawater.  In addition, the thin profile of the slotless stator architecture provides less fluid resistance than more traditional actuators.  Mechanically speaking, the 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.

With more than two decades of experience in the design and production of slotless motor kits, ThinGap leverages its proven designs to deliver engineered solutions to support both commercial and defense applications underwater. With standard products ranging in size from 25 mm to 393 mm in outer diameter, ThinGap’s highly scalable motor technology can be modified to fit any environmental requirement.

Fourteen seconds. That is the amount of time that the crew of Apollo 13 was instructed by NASA’s Mission Control to fire their Lunar Lander’s descent engine to return their damaged spacecraft back to Earth. With the ailing spacecraft being 60-80 miles off-course, this was the critical “push” that the crew needed to correct their return trajectory. The inside of the command module was close to freezing due to most onboard systems being shut down to conserve energy, including the onboard digital timer. With the odds stacked against the crew, it was up to a mechanical backup to time the engine burn – – Astronaut Jack Swigert’s Omega Speedmaster wristwatch. While the availability of a backup seems so obvious as to be an afterthought, it was in fact a decision that had been qualified by NASA five years earlier.

Flight qualification is a process by which components intended for space are subjected to a variety of conditions intended to replicate the harsh environment outside the atmosphere, not limited to vacuum, temperature, and shock. These tests are designed to push systems to their very limits to ensure functionality, an achievement that ThinGap motors have accomplished in support of an upcoming NASA mission.  Qualifying anything for use in space, whether it be a ThinGap brushless DC motor or a commercially made Omega wristwatch, is an important and complex process.

The story of the watch that saved Apollo 13 began nearly a decade earlier, with Mercury-Atlas 8 in October 1962. In the early days of manned spaceflight, astronauts were not issued watches, and instead were permitted to wear their personal timepieces. For Mercury-Atlas 8, test pilot and astronaut Wally Schirra wore his Omega Speedmaster, beginning what became a long relationship between Omega Watches and NASA.

With America’s lofty goal of fulfilling recently assassinated President John F. Kennedy’s dream of landing a man on the Moon by the end of the 1960s, no detail was overlooked, including the astronauts’ watches. By the time NASA was ready to select a watch for the Apollo program in 1965, they issued a solicitation to a handful of watchmakers based off of astronaut feedback, with ultimately only three makers responding: Omega, Rolex, and Longines.

With the three brand of watches procured for evaluation, it came time to test them in the most scientific way possible… to destruction, with the following flight certification regiment having been pulled from historical documents:

1. 1. 1. High Temperature– 48 hours at a temperature of 160°F (71°C) followed by 30 minutes at 200°F (93°C). For the high temperature tests, atmospheric pressure shall be 5.5 psi (0.35 atm) and the relative humidity shall not exceed 15%.
      2. Low Temperature –Four hours at a temperature of 0°F (-18° C)
      3. Temperature Pressure Chamber – pressure maximum of 1.47 x 10exp-5 psi (10exp-6 atm) with temperature raised to 160°F (71°C). The temperature shall then be lowered to 0°F (-18°C) in 45 minutes and raised again to 160°F in 45 minutes. Fifteen more such cycles shall be completed.
      4. Relative Humidity –A total time of 240 hours at temperatures varying between 68°F and 160°F (20°C and 71°C, respectively) in a relative humidity of at least 95%. The steam used shall have a pH value between 6.5 and 7.5.
      5. Pure Oxygen Atmosphere –The test item shall be placed in an atmosphere of 100% oxygen at a pressure of 5.5 psi (0.35 atm) for 48 hours. Performance outside of specification tolerance, visible burning, creation of toxic gases, obnoxious odors, or deterioration of seals or lubricants shall constitute a failure. The ambient temperature shall be maintained at 160°F (71°C).
      6. Shock –Six shocks of 40g each, in six different directions, with each shock lasting 11 milliseconds.
      7. Acceleration –The test item shall be accelerated linearly from 1g to 7.25g within 333 seconds, along an axis parallel to the longitudinal spacecraft axis.
      8. Decompression –90 minutes in a vacuum of 1.47 x 10E-5 psi (10 E-6 atm) at a temperature of 160° F (71° C), and 30 minutes at a 200° F (93°C).
      9. High Pressure –The test item shall be subjected to a pressure of 23.5 psi (1.6 atm) for a minimum period of one hour.
      10. Vibration –Three cycles of 30 minutes (lateral, horizontal, vertical, the frequency varying from 5 to 2000 cps and back to 5 cps in 15 minutes. Average acceleration per impulse must be at least 8.8g.
      11. Acoustic Noise –130dB over a frequency range from 40 to 10,000 HZ, for a duration of 30 minutes.

As if the torturous and destructive test routine wasn’t enough, the watches were subsequently required to retain their accuracy within 5 seconds a day. The Speedmaster was the winner by default, with the Longines and Rolex having failed at the beginning of the first temperature test. Despite being the victor, the Speedmaster was still worse for wear, with all the luminous paint on the dial having crumbled off, yet its workings remained accurate to within an impressive 4 seconds a day.

The Omega Speedmaster has changed very little cosmetically since it’s 1957 introduction

The reasons for the Omega Speedmaster’s durability ultimately comes down to a simple, yet robust mechanical movement inside, as well as a rugged, yet elegant case that envelops it. Introduced in the late 1950s for use in motorsports, the Omega Speedmaster is a hand-wound chronograph (a watch with an integrated stopwatch function) with a minimalist black dial with white markings and protected by a domed bubble acrylic watch glass. The Speedmaster had become a favorite amongst pilots due to the highly reliability, legibility, and most importantly, the accuracy it possessed.

Ed White on a spacewalk during Gemini 4

With the Speedmaster now qualified for all manned space missions and extravehicular activities, they became standard issue to NASA’s crews.  In June 1965, Ed White wore his on the first American spacewalk during Gemini 4. When Apollo 11 landed on the Moon in July 1969, mission commander Neil Armstrong left his in the Lunar Lander to serve as a backup timer as the Lander’s internal electronic timer had malfunctioned. However, Buzz Aldrin chose to affix his for the moonwalk, making the Speedmaster the first watch worn on the Moon.

Buzz Aldrin in the Lunar Module ahead of lunar landing

Despite its previous widescale acceptance by the aeronautical community, the Speedmaster’s defining moment came during Apollo 13 in April 1970, after an exploded oxygen tank crippled the Apollo Lunar Module en-route to the Moon. With their vehicle critically damaged, making their lunar mission impossible, the astronauts agreed to forsake all creature comfort, and powered down all support systems, except for basic life support, including the digital mission timer to save power. Jack Swigert’s manual 14 second burn, timed on the watch, ensured that their freezing capsule re-entered the at the right angle, instead of their trajectory which would have bounced them off the Earth’s upper atmosphere and back into space.

Astronaut Jack Swigert during spacesuit fitment

The Speedmaster flew with NASA for the rest of the Apollo moon missions, and subsequent NASA programs. When Apollo-Soyuz, the first international space flight, flew in 1976, both the American astronauts and Soviet cosmonauts were seen wearing Speedmasters–an interesting detail given that cosmonauts had previously worn exclusively Soviet-made watches as a way to promote their domestic industry and were regularly worn aboard the Mir Space Station.

The Speedmaster was re-certified by NASA in 1978 for the Space Shuttle program, yet again undergoing the same rigorous regime. Through the Shuttle program, the Speedmaster remained standard issue for all astronauts, and in the 1990s, NASA and Omega collaborated on a clean-sheet watch, designed with the needs of modern astronauts in mind. This joint venture resulted in the Speedmaster X-33, which saw the purely mechanical watch upgraded to a modern, battery-powered computerized watch. Despite being superseded by a modern replacement, the original Speedmaster has still been seen worn aboard the International Space Station.

German Astronaut Alexander Gerst is seen wearing his Speedmaster X-33 aboard the International Space Station

To this very day, one can walk into a jeweler and buy a watch that is cosmetically and functionally identical to what has been flown since 1962. In fact, from the mid-1960s onward, the caseback of every Omega Speedmaster Professional (affectionately referred to as the Moonwatch) bears the inscription “Flight-Qualified By NASA In 1965 For All Manned Space Missions-The First Watch Worn On The Moon”.

1970s Omega print ads detailing the Speedmaster’s involvement with NASA and the Apollo program

ThinGap has supplied flight-qualified motors to NASA in support of their upcoming PACE mission. Focused on monitoring the overall health of worldwide oceans and atmosphere by monitoring the color of the seawater, PACE is set to launch in February 2024 from Kennedy Space Center. ThinGap is honored to support this mission by supplying custom LS Series slotless motors that drive the satellite’s primary sensor, the Ocean Color Instrument. Additionally, ThinGap has supplied more than 2,500 motor kits in support of a major commercial constellation.

Works Cited:

OMEGA and Apollo 13 – The 14 critical seconds between success and failure

NASA Testing Regime for the Omega Speedmaster Moonwatch

Apollo 13 — A Life-Saving Fourteen-Second Burn Timed With The Omega Speedmaster Professional

A Watch Made for Space but Ready for Anything

Actual Pictures Actually Showing The Speedmaster Professional Actually Being Used For EVA, Today (Well, In 2014)

Watches used in space exploration

Designed around a low profile cogless motor with an optical encoder, precision bearing set, and anodized aluminum housing, the unit is for use in a ground-based NASA optical platform.

ThinGap recently shipped a housed version of its LSI 267-32 motor kit to a commercial customer in support of a ground-based NASA application, adding to the list of successful deliveries of housed units. Built around the company’s slotless 267 mm outer diameter BLDC motor kit, the H-LSI 267-32 integrates the high performance motor with a precision bearing set, and an optical encoder into a lightweight, Chem Film coated aluminum housing.

As a turnkey solution designed for a ground-based optical platform, this unit adds to ThinGap’s repertoire of housed and framed motor assemblies. The assembly measures 282 mm in diameter, with an axial height of 86 mm, and an internal aperture of 190 mm; the whole assembly weighs in at 8.34 kg (18.4 Lbs.), and produces a continuous torque output of 12.5 N-m, with a peak 1-second torque of 184 N-m.

Customers often come to ThinGap in need of a motor kit, wanting to take advantage of the low-profile, lightweight, and frameless architecture that is ideal for deep system integration. Yet, the time and cost of developing a housed solution are not lost on program managers and developers, so the availability of a ThinGap-led, fully engineered direct drive assembly provides a tangible advantage.

Beyond zero cogging, ThinGap’s air core motor kits have near zero Eddy current, and a harmonic distortion of less than 1%, so torque output is directly proportional to current. The resulting smooth motion and linear output makes them perfect for use in precision applications. ThinGap’s LS Series of slotless motor kits range in size from 25 to 267 mm in diameter, torque from 0.1 to 12 N-m continuous, and voltages from 24-400 volts.

For additional information on custom motor development, please contact the company at [email protected] or visit www.thingap.com.

As part of regular documentation updates, ThinGap recently outlined the process by which commercial-off-the-shelf motor kits are modified for space applications. Titled “ThinGap Space Qualification Capabilities Statement,” and available on the Compliance Information page, this one-page document provides an overview on how the company handles modifications to meet the needs of both LEO applications typical of NewSpace, as well as more rigorous Government space programs, including NASA and defense applications.

ThinGap’s brushless DC electric motor kits are high quality, high performance motion components. The company has an extensive space heritage with commercial, scientific and military programs, including 2,500 motor kits supplied for an undisclosed LEO satellite constellation, 20+ space-grade programs actively being supported, and delivery of flight-grade kits for NASA’s PACE Program.

ThinGap has a standard approach and delivery set for providing space-grade motors, as well as the capability to support more stringent customer-specific flow downs, in addition to offering the space-rated off-the-shelf TGR Series.

Commercial Space Standard

ThinGap has established a commercial standard to provide “space-grade” motor kits using a set of process and material callouts. Essentially any of ThinGap’s standard motor kits can be upgraded to a space standard. The defined space upgrades provide an affordable option, especially for high volume and rapid reaction programs, such as commercial LEO applications.

The baseline for commercial space motor kits includes the following:

• A controlled Materials and Processes (M&P) list
• Use of low outgassing materials, per NASA guidelines
• Class 3 PCBs
• Leaded solder and IPC J-STD workmanship
• Raw material certifications
• First Article Inspection Reports

Additional Supplemental Deliverables

ThinGap can quote a wide range of customer requested flow downs applicable to motor deliveries. When requested, the company can engage third parties to satisfy requirements outside its on-site capabilities, including certain types of testing and analysis. Optional customer requested deliverables include i.) structural and finite element analyses, ii.) on-site source inspection, iii.) DFARS compliant material sourcing and iv.) thermal vacuum testing conducted by a third party.

At the time of quoting, ThinGap requests a customer-provided compliance matrix with any required callouts or flow downs to be completed and returned by ThinGap.

Summary

The company prides itself on its heritage and being able to support a range of requirements called for by space applications.  Default deliverables are the baseline of the company’s capabilities, and can be supplemented with additional customer-specific requirements as required.

To view and download the statement, click here.

ThinGap was pleased to learn of the acquisition of Sierramotion by its parent company Allient, formerly known as Allied Motion Technologies. Sierramotion is a company that ThinGap has a solid history of working with to provide tailored mechatronic solutions for customers in the robotic, medical, defense, semiconductor, and industrial fields.

John Baumann, President of ThinGap commented “I see lots of potential officially being on the same team as Sierramotion, and expect to work even more closely with them going forward.”

Sierramotion and ThinGap’s working relationship was first announced back in 2019 and has been mutually beneficial ever since.  Sierramotion even mentioned ThinGap’s LS Series as a market leader in direct drive motors on their website back in 2021. With such a shared history of collaboration, this news offers great potential for the future.

With an outer diameter of 146 mm, the LSI 146-16 fits between the LSI 130 and LSI 152 motor kits

The axial height of the newest addition to the LS Series is only 16 mm tall

ThinGap continues to build out its LS Series of slotless motor kits with the latest release, the LSI 146-16. The new LSI 146-16 kit has an outer diameter (OD) of 146 mm, and an axial height of just 16 mm. With a total mass of just over 460 grams, it offers a continuous torque output of 1.48 N-m, and peak 1 second torque as high as 18.1 N-m.

Despite a maximum operating speed of up to 1,600 RPM, the LSI 146-16 was designed for use in slower speed gimbal systems, joining other LS Series models that have found uses in this application. Multi-axial gimbal systems leverage the benefits of high performance cogless Ring Motors, such as ThinGap’s industry leading LS Series, to directly drive movement and maintain position, while offering significant Size, Weight, and Power (SWaP) savings.

Using its proprietary 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, size and weight penalty that plagues them. ThinGap’s LS Series of slotless motor kits range in size from 25 to 267 mm diameter and torque from 0.1 to 12 N-m continuous and voltages from 24-400 volts.

Left to Right-Joseph Kay, PhD-Director of Engineering, John Baumann, President of ThinGap, and Robby Estep and Dustyn Strosnider from NASA Goddard Spaceflight Center

This past week, ThinGap hosted visitors from NASA who delivered their appreciation for the support of their PACE mission. The team from NASA Goddard gave a progress update on the mission, as well providing a Certificate of Appreciation that the ThinGap team can proudly display. NASA’s PACE mission is focused on monitoring the overall health of worldwide oceans by monitoring the color of the water, as well as atmospheric observation.  ThinGap is honored to support this mission by supplying custom LS Series slotless motors that drive the satellite’s primary sensor, the Ocean Color Instrument. NASA’s PACE Spacecraft is schedule to launch from the Kennedy Space Center in January 2024.