Twist Capsule Assemblies/Mechanisms (Electro Mechanical Assemblies)

Electro Mechanical Assemblies, Twist Capsules, and Cable Wraps supporting Space, Aerospace, and Defense customers.


Cristek combines a quarter century of interconnect design with world class manufacturing experience to support its strategic aerospace and defense customers with box build and electro mechanical assembly. Cristek specializes in high density packages where complex wiring is integrated with electro mechanical and electronic component



  • Do you have an old design with obsolete components that requires updating prior to your next build?
  • Have spiral development and performance upgrades to your major system or subsystem “crowded out” your box or assembly to the point that you need a major redesign?
  • Need a supplier who documents its materials, processes and assembly instructions providing you no doubt that each assembly will be made exactly the last and that the components used are traceable and precisely what you have specified?
  • Do you need to outsource some of your assembly to free up internal staff and/or meet supplier subcontracting goals for diversity?

Twist Capsules

A niche breed of electro mechanical assembly is a called “twist capsule” or “twist cap.” This unique construction is used when signals between and input and output must be rotatable in relation to each other and when a traditional cable wrap assembly or slip ring just won’t do.

The twist capsule is an application specific design which combines structural components (stator and rotor) with situationally appropriate interconnect construction throughout (connectors, cable, flex circuitry, etc.). The resulting assembly provides up to a total rotation of 360 degrees (175 degrees in either direction). This packaging approach yields a higher life expectancy and substantially lower torque than a traditional cable assembly. Twist capsules can provide higher circuit density and are typically more cost effective than a slip ring. They also beat the slip ring solution by providing higher signal quality over the system life and having the best overall torque and stability performance.

Cristek’s expertise in high density connector design (down to .025” pitch), harness and flex assembly development and precision machining are laying the foundation for this emerging product line to become a major focus for future investment and growth. Due to the critical need for cleanliness and FOD control to optimize twist capsule performance, assembly is performed in Cristek’s “control room.”


Orion Series™

  • Effective Slip ring alterative
  • Designed for power transfer, can carry up to 90 Amps in a form factor aperture of 0/12.8
  • Can use one to 8 connector interfaces transmission of up to 111 discrete lines
  • Fully redundant power pins available with multiple points of contact
  • Heat sinking to chassis body to meet thermal requirements


Hydra Series™ Signal and Power: Commercial / Space

  • Small form factor, high signal count and rotational limitations.
  • Intended for cost-driven terrestrial lab, field, military, or commercial space applications
  • This TCA meets environmental specs that require resistance to temperature, radiation, and vacuum
  • Radiation-tolerant COTS electronics or screened to GSFC EEE-INST-002 Level 1 or 2
  • Up to 740 discrete lines with several protocols used


Aquila Series™ High Frequency and Transmission: Space Applications

Aquila is Cristek's flagship space-qualified dynamic signal transmission mechanism in the TCA® product line. This mechanism has been designed to meet the performance and environmental requirements for the most demanding space missions. The system can support up to 15Gbps, low torque, and signal counts up to 740 across a +/-200 degree rotational platform. 

  • Up to 80dB of signal shielding IAW MIL-STD-461
  • Proprietary shielding provides cable harness level protection while supporting rotational needs
  • Designed to deliver high performance and high reliability for extended on-orbit missions
  • Space variant with electronic components screened and qualified to GSFC EEE-INST-002 Level 2 or higher
  • Structural, Thermal, Radiation Analyses provided to Specific Mission or Orbital profiles
  • Wide array of interfacing configurations and geometry



If you have a rotational package with I/O signals – give us a call to see what we can do for you!


Standard Sizing Options Below - all dimensions are customizable to serve your design

TCASeriesTMOD (in/mm)Aperture (mm/in)Bundle 
Flex Circuit / or BundleCapsule Height (mm/in)InmmInmm
1 to 831.75/1.251.2531.7500
1 to 863.5/2.53.588.9125.4
1 to 2063.5/2.54101.61.538.1
1 to 2069.85/2.7551272.563.5
1 to 2069.85/2.756152.43.588.9
1 to 876.2/3.006.75171.454.25107.95
1 to 882.55/3.258203.25.5139.7
1 to 888.9/3.5021.5546.119482.6
5 to 2063.5/2.53.588.9125.4
5 to 2070/2.754.25107.951.7544.45
5 to 2076.2/3.006.5165.14101.6
5 to 2076.2/3.007.25184.154.75120.65
5 to 2082.55/3.257.5190.55127
5 to 2095.25/3.75102547.5190.5
5 to 20101.6/4.0012.5317.510254
5 to 20108/4.2514.5368.312304.8
5 to 20114/4.5021.5546.119482.6
All capsule heights can use structural members to bridge system interfaces
Cells in Grey are directly compatible with Quantic BEI optical encoders sizing 
Grouping Option - 
26/28 AWG copper wire, 34 conductors, rated to 300V
22 AWG copper wire, 10 conductors, rated to 18kV
100 ? coaxial cable, 8 cables
75 ? coaxial cable, 8 cables
50 ? coaxial cable, 8 cables
USB 3.0 cable, 3 cables*
Fiber Optics, 12 Discrete (MT)*


Tiered performance Options Below - The Aquila Series is bundled with comprehensive Thermal, Structural, and Radiation Reports. Users can conveniently utilize all available options in the Interfacing and Material Options below.

MechanismsTCASeriesTM
OrionHydraAquila
Intended MarketComm.            SpaceComm.        SpaceSpace
Certification and AnalysisYesYesYes
Output Torque (continuous) N-m.1 - .5 N-m.2 - 1.0 N-mConfig.
Hysteresis Torque<20%(1)<10%(1)<5%
Typical Signal Transfer Count9 - 11137 - 14837 - 740
SizeConfig.Config.Config.
Vacuum capability YesYesYes
Mass<1.5 kg<3.5kg<4.9kg
Precision Alignment Need1-Axis (Radial) (2)2-Axis (Axially) (Radial) (2)2-Axis (Axially) (Radial) (2)
Low OutgassingAvailableAvailableStandard
Angular Range<±125(3)<±210(3)<±355(3)
Rotational speed25°/s60°/s60°/s(4)
Radiation Tolerance krad(Si)50 (4)50(4)100
Lifetime Rotational Fatigue1.1E05 - 1E061.00E+06Config.
On-Orbit Equivalent for Rad and Fatigue1-5 Years on Orbit3 - 5 Years on Orbit3 - 15 Years on Orbit
Max Data Transfer Rate5 Gbps10 Gbps15 Gbps
Power Throughput Capacity.66 - 1.5 kW>2.7 kWConfig.
Operating Temp. (°C)-40 ~ 80-55 ~ 85-55 ~ 110
Storage Temp. (°C)-60 ~ 90-60 ~ 90-60 ~ 90
Notes(1) The torque profile is primarily shaped by geometric factors, whereas in a motor-driven system, this aspect assumes a diminished significance.
(2) System Level Alignment depending on interfacing
(3) Range can be reduced or increased depending on application to reduce weight and increase signal performance
(4) Can be adjusted for mission performance trades with shielding weight