System of Guidance Sensors (SDG)
Space Research Institute of the Russian Academy of Sciences is involved in the creation of the International space Astrophysical Observatory (WCO-UV), designed for space exploration in ultraviolet range with high angular resolution.
The observatory is based on a "Spektr-UF" s/c with a T-170M telescope onboard.
In order to solve the observatory tasks the telescope should be pointed to the observed object with high accuracy and hold in the specified position for a sufficiently long time intervals.
To do this, it is planned to use in the telescope the System of guidance sensors (SDG) being developed at the Optico-physical department.
Guidance sensors are located in the telescope's focal area and are capable to observe the stars with a magnitude of 15-17 through its optical system.
Data from the guidance sensors is transmitted to the data processing unit, where it is processed to determine the telescope attitude in inertial space
Arrangement of equipment in the telescope's instrumentation compartment
Prototype of the guidance sensor
Guidance sensor engineering model
Main characteristics of SDG
| Number of guidance sensors | 3 |
|
Power consumption, W: - with one operating guidance sensor - with two operating guidance sensors - with three operating guidance sensors |
less than 20 less than 30 less than 40 |
| Cable length between Data processing unit and guidance sensor, m | 4 |
| Probability of failure-free operation | more than 0,95 |
| Lifetime, years | 10 |
|
Rms of determining the deflection angle - around the axis perpendicular to the line of sight, arcsec - around the line of sight |
0,01 15 |
| Data updatement frequency, Hz | 0,5 |
Guidance sensor characteristics
| CCD-matrix | "Sfera-1000" |
| Number of CCD pixels(pixel size, mkm) | 1024х1024(16х16) |
| Mass, kg | 0,7 |
| Dimensions, mm | 152х112,5х45,8 |
| Operating temperature range, °С | +15..+25 |
| Ultimate star magnitude | +17 |
| Field of view, arcmin | 3х3 |
| ADC capacity, bit | 12 |
| Gain | 5..15 |
Characteristics of data processing unit
| Mass, kg | 4,3 |
| Dimensions, mm | 230х178,5х154 |
| Operating temperature range, °С | -20..+40 |
| Redundancy | cold redundancy |
| Output interface | MPI(GOST Р 52070-2003) |