HORACE (Horizon Acquisition Experiment) is an experiment flying on REXUS 15/16. The Sensor-system is supposed to evaluate autonomously its attitude relative to the earth. What we want to determine on our flight is whether this approach is really apt to acquire the attitude even under stress conditions.
The System is meant to consist of a camera and an embedded system on which an algorithm is working. While system is bulkhead mounted to one of the experiment modules, the camera is positioned in a 90° angle and so it is skin mounted, watching outside through a hole in the shell of the rocket and taking pictures.
They will be processed by the algorithm, that means by recognizing the silhouette of the earth it calculates a vector to the earth centre. Using several processed pictures the attitude can be determined.