Method of working
The system contains two independent instrument systems for excellent reliability in conjunction with the sophisticated software. The professional version contains additional instruments which provide autonomous control of all functions.
The position is measured by sensing the ground, using a principle similar to that of the optical computer mouse; the difference is that the positioning system continues to work at altitudes of up to 20-30m, and even at the onset of dusk. A movement sensor senses the ground in flight, i.e. it virtually replaces the eyes of an airborne pilot. Almost every ground surface exhibits contrast, and this allows the system to detect all relative movements in the horizontal direction, just as accurately as a computer mouse on its mat. The supplementary attitude stabilisation features an artificial horizon and three electronic gyros, and works completely independently of the prevailing visual conditions.
As a result, the HeliCommand is capable of stabilising the helicopter in the horizontal attitude independent of the visual circumstances (in contrast to previous types of stabilisers). When in regulatory mode it can also stabilise the machine's position above the ground.
The HeliCommand-PROFI was developed for commercial applications, and is equipped with additional instruments, including a ground distance sensor for automatic landing, and an air pressure sensor for altitude stabilisation, plus a second redundant ground sensor for drift measurement. The Profi version also contains ultra-precise hardware, enabling it to provide enhanced stability and precision even in unforgiving mission conditions.
Of course, in exceptional visual conditions, e.g. in the dark, above water, over smooth floor coverings or a featureless snow blanket, the visual sensing systems are unable to supply a signal. If this should occur, the other airborne instruments automatically assume the stabilising role. Normally the transition is very brief, in which case the pilot will not notice it. If it lasts longer, the stabilisation automatically switches from “position mode” to “horizontal mode”. In this case the pilot will notice the difference, as he has to compensate for any slow drift by giving straightforward control commands. Even in this situation the level of stabilisation is equivalent to that provided by conventional “inertial control” technology, i.e. it provides tilt stabilisation, as if you had switched off the altitude regulation and several other features of the HeliCommand.
Action chart: HeliCommand 3A, 3D, Rigid
Für kommerzielle Einsätze, Luftfotografie etc. ist der HeliCommand-Profi vorgesehen, der mit weiteren Instrumenten und besonders präziser Stabilisierung ausgestattet ist.
