The Challenge
Antenna Pointing Systems (APSs) are lightweight, compact systems responsible for aligning antennas to satellites for the transmission and reception of data. One such kind of APS is being utilized today on airplanes to provide in-flight entertainment via on-board Wi-Fi, placed on the exterior of the plane, these devices are often exposed to environments with dramatic changes in temperature.
Additionally, the device must be lightweight and have a minimal profile to limit drag on the aircraft, thus saving fuel costs. Transmitted and received between the aircraft and Fixed Service Satellites (FSS), Ka or Ku Band channel frequencies require elevation and rotation of the beam as the aircraft transits.
Today, there is a push towards LEO/ MEO High Throughput Satellite (HTS) services in aircraft, this antenna system necessitates extremely dynamic and specific positioning to sustain the appropriate transponder performance when rapidly tracking orbiting and setting satellites.

Image Credit: Celera Motion
The Solution
The Celera Motion Infinity Series motor is a direct drive motor with an ultra-thin low profile that is also arc-shaped. Parts of the motor can be utilized individually or combined to produce a full circumference up to 360 degrees.
The ironless direct-drive motor provides smooth motion critical for precise positioning, necessary when making specific movements. Pairing the motor with the Celera Motion IncOder, a high resolution rotary inductive position sensor allows for dependable position sensing. As a standard product, the rotary sensor is available up to 595 mm outer diameter (OD) form factor.

Image Credit: Celera Motion
The Benefit
The lightweight, ultra-thin Infinity Series offers the low profile required for an APS with minimal weight requirements. The ability to design any outer diameter (OD) size enables the Infinity to take to any antenna shape. When employing the 360-degree design, the large through-hole allows space for the routing of cables and additional system elements.
Dynamic motion and high-power density, paired with the durable and reliable inductive position sensing IncOder, makes it possible for the antenna to be positioned rapidly, an attribute that ensures a high transponder throughput.

Image Credit: Celera Motion
Specifications
Table 1. Infinity Series Motors. Source: Celera Motion
|
|
Configuration |
Axial arc-segment forcers |
Continuous Torque |
0.65 to 63.4 Nm |
Peak Torque |
1.95 to 190.2 Nm |
Outer Diameter |
112 to 765 mm |
Height (Axial Length) |
20 to 40 mm |
Peak Current |
3.4 to 4.5 Amps |
Table 2. IncOder Series Inductive Encoders. Source: Celera Motion
|
|
Resolution |
22-bits possible |
Repeatability |
+/- 1 bits |
Outer Diameter |
37 to 595 mm |
Operating Temperature |
-60 to 105°C possible |

This information has been sourced, reviewed and adapted from materials provided by Celera Motion.
For more information on this source, please visit Celera Motion.