DESCRIPTION
«System for locating The Mecca City by using the GPS satellite location system and tne relative instrument" Technical Field This invention relates to the technical sector of the production of electronic instruments and particularly of watches .
Specifically, it relates to the production of watches which use the GPS satellite location system, providing their implementation with a further function capable of locating immediately the position of a fixed specific place. The present invention consists of a system capable of locating The Mecca City, by using the GPS satellite location system, that hereafter we'll call simply GPS, by means of a specific electronic instrument preferably incorporated in a watch. Background art
Everybody knows that believers of Islam are used to pray in different hours and periods by ideally looking towards The Mecca City. For this purpose, they are used to orientate themselves following their sense and experience, by pointing the North and moving accordingly. Anyway, they don't use instruments capable of indicating exactly the position of their Holy City towards which they turn for praying. Other known electronic systems which use the GPS system, are capable of determining where the user is, in a certain moment, in any part of the planet. Such instruments, used in various sectors and particularly in the nautical sector, are useful for
locating h s own position but they are not used to locate the position of a place different from the one where he is, and are even less used to locate a specific place, not even The Mecca City. Other known systems consist of watches which embody the GPS satellite location system in order to give the exact position on the earth to the users wearing them. But even these watches don't let the user locate simply and immediately The Mecca City from the place where he is. This invention aims at eliminating the above-mentioned drawback and providing a system capable of locating simply and immediately The Mecca City from everywhere in the world. Disclosure of invention The technical solution which has been adopted consists of a system capable of indicating, on a display unit, the position of The Mecca City, by using the GPS satellite location system, with the characteristics described m the separate claims. Other characteristics of this system are the object of dependent claims . The advantages resulting from this invention essentially consist of the fact that it's always possible to locate The Mecca City from everywhere n the world; that its location is precisely and not approximately indicated; that its location is found quickly and immediately with no need of calculations or conjectures; that believers save time when they are going to pray turning towards The Mecca; that this system is incorporated n a small instrument, preferably a watch, that
the user wears without problems; that it has a reasonable cost and can be largely commercialised; that no similar instruments exist and it represents the best solution to the proposed technical problem. Reduced to its essential structure and with reference to the figures of the enclosed drawings, a system for locating The Mecca City according to the invention, comprises: means to receive information about the geographical coordinates with a radio-receiver capable of reading digital signals coming from the group of geo-static satellites; means to find the position of the magnetic North, with any known magnetic system capable of capturing data; electronic processing means of geographical Information, with a microprocessor equipped with specific firmware; - means to display the position of The Mecca City, determined on the basis of the data received, with a digital display system. The instrument, which involves all the functional blocks we've just described, has the advantage that, thanks to the integration allowed by microelectronic, it's contained into a watch dimension, a typical sport watch like the one worn by seamen and mountaineers, or into another small separate instrument .
The system is conveniently based on the known method of triangulation, that seamen have always used to determine the course to follow. In this case, it is used to determine the direction to which one must turn, in order to be certain he's
looking towards The Mecca City, without denying however the observations we are going to make.
In order to determine the direction to follow, the user must know the following data: 1- the direction of the magnetic North;
2- the co-ordinates of the position where he is;
3- the co-ordinates of the destination.
Data relative to point 1 are determined by means of a magnetic system, like a compass' one; data relative to point 2 are determined by capturing signals coming from GPS satellites; data relative to point 3 are fixed.
For the implementation of this system is conveniently necessary that a microprocessor (2) does a series of mathematical calculations, based on the principles, formulas and equations below described.
With reference to F g. 1: point (A) is the position of the user, point (B) is the position of the magnetic North, point (M) is the position of The Mecca; we insert the three points into a reference Cartesian system, considering that the user is in the northern-eastern hemisphere; by uniting the three points with a line, we obtain a triangle with three different sides and angles (hereby the name of technique of triangulation) . Being α' the internal angle between the two segments AB and AM, β' the internal angle between the two segments AB and BM, and λγ' the internal angle between the two segments AM and BM: the user must calculate the angle Λα' , i.e. the angle formed by the "User - The Mecca" guideline (segment AM) with the "User -
Magnetic North" guideline (segment AB) , as we call " guideline" the line on which each of the above-mentioned segments lies. In order to calculate the angle Λα' , we resort to the Bπggs ' Formulas of the plane trigonometry. Having known the three sides of any triangle, is in fact possible to calculate the three internal angles, with the following formulas:
(3) tg(γ !2) =
where (a) indicates the length of the segment AM, (b) the length of the segment AB and (c) the length of the segment BM. The length of these three segments can be worked out from the co-ordinates of point A (where the user is) and the ones of point B (of the magnetic North), as we are going to describe. As we call the co-ordinates of the geographical point where the user is (provided by the GPS) j and y
1; the co-ordinates of the magnetic North x
n and y
n, the co-ordinates of The Mecca x
m and y
m, we consider the following relations:
(5) α = rf(xm - x\)2 + (ym - y 2
(6) c = -κj(xm - χn)2 + (ym - yn)2
At this point, as we know the co-ordinates of the three points A, B,C, we can calculate the length of the three segments a,b,c, with the formulas indicated above with numbers (4), (5), (6). Consequently, with the reverse formulas (7) of the formula (1), we obtain the angle λα' , i.e. the angle formed by the guideline AB (User - magnetic North) with the guideline AM (User - The Mecca) .
With reference to Fig. 2: conveniently, the receiver block (1) is a normal GPS, which measures the value of the longitude and latitude of the point where the user is, as from the strings of bit coming serially from the satellite, through radio-waves. We do not describe the technical details of the GPS, as they are known, easy to find and not important for the purposes of the present relation. The block (2) is constituted by a microprocessor, aimed at doing the mathematical calculations we've ust described and handling the displaying of the desired direction, by means of a liquid crystal display (3) . The firmware necessary to the microprocessor may be contained in a 'ROM' memory (4). The magnetic sensor for finding the North is block (5) . Feeding will be supplied by a battery (6) . In order to allow the user to have a clear and effective indication of the direction towards which he must turn, so that he has in front of him The Mecca City, we can conveniently image to have a liquid crystal display of graphic kind, where
three lines are depicted: the first one corresponds to the "User - Magnetic North" guideline (9), and its inclination again the border of the display is computed by the microprocessor and then depicted on the screen itself, on the basis of the calculations resulted from the equations (4), (5), (6); the second one corresponds to the "User - The Mecca" guideline (8), and its inclination again the border of the display is computed by the microprocessor and then depicted on the screen itself, on the basis of the calculations resulted from the equation (7); the third one is a reference line (7), designed on the basis of the indications from the magnetic sensor, showing the direction of the North, and must coincide with the "User - Magnetic North" guideline (9) . In practice, it's like having a compass needle, that, rather than being metal, is represented by a line on the display (7), which overlays another line (9) showing the user the direction towards which he must turn. In this way, just as in a conventional magnetic compass it's necessary to align the magnetic needle with the fixed indication on the quadrant, so in this instrument it's necessary to align the line produced by the magnetic sensor (7) with the one calculated and depicted on the same display by the microprocessor (9), on the basis of the data of the GPS. The values of the co-ordinates of The Mecca City are pre-fixed in the firmware, so that they cannot be modified. In order to reduce energy consumption, the instrument is on just when it's used, and it switches off automatically after a fixed period of time. Externally, the instrument could
appear like a watch (we can see a schematic representation of its face in Fig. 3), where, m addition to the Information about the hour and the current date, the co-ordinates of the user's position and the three lines we've ust described will be shown on the screen.
Suitably, the realization on industrial scale of the present invention implies the design of a "custom" microprocessor which implements all the functions of computing and handling of the display, while the GPS interface can use the integrated circuits normally used in the GPS. It's then necessary to develop the handling firmware and create the mould for stamping out the plastic material which constitutes the frame of the instrument . In practice, details of execution may vary, being however equivalent, in form, size, arrangement of components, type of materials used, but still remain within the range of the idea proposed as a solution and, consequently, within the limits of the protection granted by this patent for industrial invention. Brief description of drawings The attached drawings are practical examples of the invention, but are not to be considered restrictive.
Fig. 1 represents schematically a reference Cartesian system, which, in this case, is constituted by the Greenwich meridian (the one passing through the city of London) for the ordinate, by the Equator line for the abscissa. Point (A) indicates the position where the user is, point (B)
indicates the position of the magnetic North, point (M) indicates the position of The Mecca.
Fig. 2 shows the block diagram of this system, constituted by: a receiver block (1), that is a normal GPS, which measures the value of the longitude and latitude of the point where the user is, as from the strings of bit coming serially from the satellite, through radio-waves; another block (2) composed by a microprocessor, aimed at doing mathematical calculations and handling the displaying of the desired direction, by means of a liquid crystal display (3) . The firmware necessary to the microprocessor is contained in a 'ROM' memory (4), while the magnetic sensor for finding the North is block (5) . Feeding is supplied by a battery (6) . - Fig. 3 shows a schematic representation of the face of the instrument, or the watch, incorporating this system, where, in addition to the Information about the hour and the current date, the co-ordinates of the user's position and the three lines will be shown on the screen as well. These three lines indicate the angle formed by the "User magnetic North" guideline (9) with the "User - The Mecca" guideline (8), on the basis of the GPS data. Furthermore, the reference line, depicted according to the Information from the magnetic sensor which indicates the magnetic North (7), and a symbol which identifies The Mecca City as it is located, will be shown on the screen as well. In practice, the details of execution can vary in accordance
with the shape, size, position of the elements, type of materials used, without however, straying from the principle of the solution adopted and therefore remaining inside the boundaries of protection granted by this patent.