NSS sun sensor

NSS Fine Sun Sensor


The sun sensor determines the spacecraft body angles with respect to the sun. It accepts configuration commands and outputs digital angles and telemetry over a serial interface to the on-board computer. The unit is powered from unregulated DC power from the spacecraft.

The front surface of the sensor is a mirror with slits cut in the reflective metal. Sunlights passes through these slits and then through an optical filter. Below this is an array of photosensors interfaced to a micro-controller.

The charge on the photosensors are read by the micro-controller, which processes the image and computes the sun vector. The vector and other telemetry is returned to the spacecraft through the serial interface.

  • Features
  • Performance
  • Product properties
  • Documents
  • Accurate determination of sun-angle
  • Four sensors can achieve full sky coverage
  • Used in conjunction with a magnetometer or simple attitude control
  • Can be used as saf°e-mode sensors on gyro or star-mapper controlled systems
  • Digital architecture
  • High accuracy
  • Wide field of view
  • Small size and mass
  • Low power
  • Simple to interface
  • Field of view 140°
  • Update rate 5 Hz
  • Accuracy +/- 0.1°
  • Digital I/F: UART, SPI, I2C, CAN or RS-485/422
  • Mass: 35 grams
  • Power: 7.5 mA average, 26 mA peak
  • Size: 34 mm x 32 mm x 21 mm
  • Operating temperature: -25°C to + 50°C
  • 15g rns random, 1000g shock (qualification levels)
  • 10krad total dose (component level)
  • Power Supply: 28V DC nominal ( 5V to 50V)