Craters in the surface of the Moon. Elements of this image furnished by NASA's Scientific Visualization Studio.

Electrical Propulsion Pointing Mechanisms

Beyond Gravity delivers high-performance pointing mechanisms for electric propulsion thrusters, enabling precise and efficient spacecraft maneuvering.

Bert Menhardt Sales Manager Thermal & Mechanisms

Beyond Gravity is a leading supplier of high-performance pointing mechanisms for electric propulsion thrusters, also known as thruster gimbals. Thruster gimbals are increasingly being used on commercial satellite platforms and scientific spacecraft due to their fuel mass efficiency advantages.

Beyond Gravity's pointing mechanisms support electric propulsion thrusters in their nominal position during launch, by means of a dedicated hold-down and release mechanism if necessary. They also reduce the mechanical loads on the thrusters via dedicated damper elements. Upon its release, the thrusters can be tilted around two axes using two actuators, which drive the platform either via a strut-linkage around a spherical joint or a cross gimbal type arrangement. This allows for high-accuracy thruster orientation.

A third axis can be realized with a robotic arm deployment mechanism. This provides a larger pointing and deployment range, which can be useful for off-loading the momentum wheels needed for spacecraft stabilization.

Our Experience

  • 10+ different mechanisms developed
  • 10+ sizes/types of thrusters supported (Hall effect and ion)
  • 23 models delivered
  • 21 flight models in orbit
  • 54 mechanisms in production
  • 25+ years of development and engineering

The Gateway space station, an essential element of NASA’s Artemis program, will serve as humanity’s first space station in lunar orbit supporting crewed and uncrewed missions to the surface of the Moon and future deep space exploration missions. Maxar ordered a pointing mechanism from Beyond Gravity.

APPMAX Family

The Beyond Gravity APPMAX Family is a series of low-cost, standardized, modular, and scalable 2-axis and 3-axis pointing mechanisms for electric propulsion. The APPMAX Family can accommodate a wide range of thruster types and sizes, making it a versatile solution for a variety of spacecraft applications.

The APPMAX Family is used for:

  • North/South and East/West station keeping
  • Compensation of center of gravity shift
  • Orbit raising and dropping
  • Momentum wheel off-loading
  • Graveyard de-orbit at spacecraft end of life
  • Interplanetary travel
Aappmax2-H-Single

APPMAX2

The APPMAX2 is a low-cost, easy-to-integrate pointing mechanism for electric propulsion. It is designed for simple integration without zero gravity devices and easy scaling to support a wide range of thruster types and sizes, including thrusters of 1-5 kW. The APPMAX2 points in a 15° cone.

APPMAX2-H

The APPMAX2-H is upscaled for a 50 kg thruster and equipped with a hold-down and release mechanism (HDRM).

APPMAX2-XS

Beyond Gravity is preparing a downscaled version of its popular APPMAX2 pointing mechanism for future constellation satellite missions. Smaller satellites are becoming increasingly popular, and they need smaller, lighter pointing mechanisms. The APPMAX2-XS is designed to meet this need, offering the same high performance and reliability as the APPMAX2, but in a smaller and lighter package.

Download our datasheet on the APPMAX - Family
APPMAX3-HDRM

APPMAX3

The APPMAX3 is a modular deployable thruster mechanism that offers a number of advantages over traditional designs. It is flexible, lightweight, and cost-effective, and it can be configured with a variety of thrusters and pointing ranges to meet the specific needs of different spacecraft missions.

The APPMAX3 uses three stepper motor-based actuators to move the thruster module to its desired position, and it includes piping that is protected by micrometeorite shielding. The flow controller can be mounted close to the mobile plate and is equipped with radiators and/or MLI according to thermal analysis.

The baseline foresees hard, direct mounting of the mechanism at the interface to the spacecraft, but elastomer dampers can be implemented depending on the thruster allowed random and shock loads. Redundant switches for position reference are implemented, and a zero-G device is provided. Thermal and micrometeorite protection is provided for the actuators and other components as necessary.

The APPMAX3 is a versatile and powerful thruster deployment mechanism that can be used in a wide range of spacecraft applications.

Download our datasheet on the APPMAX - Family
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