Compact Star Trackers

“Azmerit” designs and manufactures compact star trackers for nano- and micro-satellites. The company is a member of the Skolkovo Foundation. It was founded by the employees of the space projects laboratory of the Sternberg Astronomical Institute of the Lomonosov Moscow State University. The team is built up by highly qualified specialists in the area of space instrumentation.

“Azmerit” has developed a Nano star tracker AZDK-1. The Nano star tracker AZDK-1 is designed to determine the spatial orientation of the structures on which it is installed with respect to the inertial equatorial star coordinate system by observing stars in the visible spectral range.

The Nano star tracker AZDK-1 successfully passed the full cycle of ground tests including functional, vibrodynamic, thermal vacuum tests and test in the night sky.

To measure the permeable magnitude of the star tracker at the time of its work (exposure 0.1 sec), observations of the starry sky were performed. The value of penetrating ability - 6.2 magnitude allows Nano star tracker AZDK-1 to work confidently across the entire starry sky. For the Nano star tracker AZDK-1, an original onboard catalog of ~ 2,400 stars has been created.

The Nano star tracker AZDK-1 has passed vibrodynamic tests. During the tests, the star tracker was subjected to sinusoidal, random (white noise) and shock effects on three axes X, Y, Z. Peak shock acceleration was 25 g with an exposure duration of 1-3 ms.

In the process of thermal vacuum testing, the pressure inside the chamber did not exceed 2∙10–6 bar. The extreme temperatures of the thermal cycle were -27 ºC and +57 ºC. The total time of the technological vacuum was 71 hours and 40 minutes. During the thermal vacuum tests, the operation of the star tracker, the change in focal length, dark currents and the functioning of the calibration shutter and the Peltier element were continuously checked.

The results of thermal vacuum tests showed that the Nano star tracker AZDK-1 provides its characteristics, and also maintains the performance, structural integrity and appearance after exposure to thermal cycles in the claimed temperature range from minus 27 ºC to +50 ºC under high vacuum.

MZD AZDK-1 successfully operates on board of the nano-satellite «Orbicraft Zorkiy», launched into orbit on March 22, 2021, on board of the nano-satellites «Orbicraft Zorkiy», «Orbicraft Zorkiy-M» and other, launched on orbit on June 27, 2023. At the moment, more than a dozen star trackers AZDK-1 carry out their mission in orbit.

The company is expanding its product line. In 2024, flight tests of the next version of the small star
tracker - MZD AZDK-2 - are planned. The new star with smaller dimensions will have higher accuracy and frequency of issuing the orientation quaternion.

Download Technical Description (pdf rus)
Parameters AZDK-1
 Entrance pupil 18,6 mm
 Field of view 22°
 CMOS geometry 1024×1280 pxls
 Pixel size 5,3 µm×5,3 µm (5,3"×5,3")
 Dimensions, mass (with baffle) 56×60×93 mm, 193 g
 Power (w/o Peltier cooler) 0,65 W
 Volume of Stellar Catalogue 2 400 stars up to 5,5m
 Accuracy σx, σyz 5''/30'' (ω<3.5°/sec)
 Update rate 5 Hz
 Supply Voltage 5 V
Оptical-dynamic stand (ODS)

Designed and manufactured optical-dynamic stand (ODS). ODS is designed to simulate the starry sky in the laboratory. Simulation of the starry sky is necessary for calibrating the Nano star tracker AZDK-1, functional tests in different modes (stationary, slow movement, fast movement), for testing the satellite orientation systems along the star field.

Simulation of the starry sky is achieved by reproducing on the focal plane of the Nano star tracker AZDK-1 an image of the starry sky as close to real as possible. To create such an image, a microdisplay is used, on which, using the control device, an image of a fragment of the starry sky is built according to the real catalog of stars up to 7.5 magnitude. To ensure maximum dynamic range when playing back images of stars, an OLED microdisplay with high contrast is used. Depending on the operating mode, certain sections of the starry sky moving in the focal plane of the Nano star tracker AZDK-1 with a given angular velocity can be reproduced.

There is also a mode for simulating the motion of the starry sky in the field of view of the Nano star tracker AZDK-1, when the spacecraft moves in a given near-earth orbit.

Download Technical Description (pdf rus)
Comm and power supply unit for nano star tracker AZDK-1
This device is designed to work with the nano star tracker AZDK-1. The unit allows powering AZDK-1 from a ~220 V and connecting it to a personal computer for further work with AZDK-1. The indicators of the unit reflect the actual voltage and amperage of the power supply AZDK-1. There is a knob-regulator that allows varying voltage of the Peltier element of the AZDK-1.
Main parameters:
Parameters Value
 Supply Voltage ~220 V
 Dimensions, mm 128×187×78
 Mass, g 740
 Сonnector DRB-9MA CAN
 Сonnector DR25S-H-CN to AZDK-1
 Сonnector USB type B (COM-port) RS-485
Azmerit ltd.©
Space сompany