Optoelectronic Elements in Non-Contact Control System for Self-Servicing of the Disabled

Known non-contact control systems of electric appliances used for self-servicing of the disabled are mainly based on PC and programmed devices that identify voice, image or bio-currents of the brain. The most tempting for completely paralyzed people, especially for those who lost their eyesight and hearing, are bio-currents identification systems. Unfortunately, nowadays these systems are mainly in the stage of development or research and, besides, are extremely expensive. For example, the system developed on the basis of PC by a group of scientists of the University of Tubingem (Germany) under the supervision of Niels Birbaumer and presented by "The Nature" costs $20,000.

During recent years some systems based on PC are known. Among them there are image identifying systems (US Patents No 5410376 and 5481622) which, by employing the video-camera checking the eye-pupil position, make possible administration of the look-control as to the images of the PC display screen (Rensselaer Politecnic Universitat design) and voice identification systems (US Patent No. 5226090) wherein the control is administered by voice commands (APT's Liaison Co. design). But these systems are rather expensive as well ($1,500 - $6,000).

Above the most common commercial models are listed. Of course, one can list a lot of such systems, still all of them have some inherent and essential technical limitations. For instance, the cheapest of the mentioned group, those voice-controlled, have somewhat reduced reliability resulting from their dependence in voice identification upon the voice timbre.

Yet, it is well known that with many people the voice timbre tends to change during the day, especially in the elder or disabled people. And during the days of catarrhal indisposition which are not few during a year the voice timbre changes sometimes to such a degree that the access to the system is practically impossible.

At one time, Professor Shmuel Amromin suggested me to take part in his research at the Institute for Advanced Studies in Arad. The ultimate objective of the said research was the development of the appliance which makes possible for people, who cannot use their hands effectively, to control easily but with proficiency electrical appliances without touching any panel sensor. In so doing, one of main prerequisites of the problem raised was to ensure a low cost of the finished product.

Together with Lev Groisberg, we, using various photo-receivers based on optoelectronic sensors, have developed and tested several versions of the device for a multi-channel remote control of electric appliances, the main prerequisite being a well-known fact that even completely paralyzed persons can, though moderately, move their heads.

All mentioned versions did not go beyond the principal idea which made a provision for coding to select the object of control by way of repeated effect upon the single non-contact panel sensor. The coding was made by a direct re-counting or with the aid of a four-rank code. Nevertheless, this approach turned out quite unsatisfactory one by virtue of the fact that it required some efforts from the user many of which might be rather tiresome.

When searching for the simplification of the problem I managed not only to state a proper idea but to find the way to its solution. The main proposition of the idea is as following:

Switching on/off any object of the multi-channel system should be performed without any coding whatsoever with the aid of a momentary single action upon the sensor of the remote control panel.

To solve this problem the multi-channel system was developed which automatically, on its own, offers consecutively to switch on/off available objects in turn.

Thus, the proposed system containing the non-contact panel, controlling center with a display where the objects of the control are mapped, and a set of radio control sockets makes possible in a simple way, without peculiar efforts, remote controlling of electrical appliances.In so doing, the user should only have a potentiality of moving his head or some other part of the body within the field of vision of the non-contact optoelectronic sensor.

Still, a "coded lock" is provided to prevent an unauthorized access to the system. To open such a lock a momentary single coded action upon the sensor of the panel is necessary and sufficient. This action results in changing the "waiting" mode of the system for the "active" mode. Special commutative circuits of active load with angles close to zero [1,2] are used to make the electric sockets control system insensitive to any commutation noise and to protect the supply line during the active loads commutation.

At first glance the project under consideration may seem quite noncommercial (the disabled's market is not very large, indeed) though in the worldwide scale there are millions of the needy. But the latter judgement is rather shallow. The point is that apart from the disabled badly bed-ridden or confined to one's armchair there exist at least three groups of people who may be in need of this system. These are elderly, old and advanced in years persons.

According to the evidence of the World Health Organization for 1999, the mentioned category of people accounts for 10% of the world population. And only about 3% of them are relatively sound, all the rest of them are sick and feeble.

The most common problems with these people are those associated with bad sight and fingers (tremor, Parkinson's disease, sclerosis, etc.). It makes impossible for them to use conventional multi-buttoned panels. Thus, taking into account the said group of potential users, the market numbers them in the tens of millions or even more. Besides, it is worth mentioning that the said market of consumers is constantly growing at the expense of medicine progress which makes humanity older.

References

1. Nisenboim G. et al. Lamp switching device. USSR author's certificate No 734900, 1980, Int. Cl. H 05 B 37/ 02
2. Nisenboim G. et al. Current commutation device. USSR author's certificate No 792591, 1980, Int. Cl. H 03 K 17/ 72