GB2068546A

GB2068546A - Method of Exchanging Maps in a Vehicle-position Indicating Device

Info

Publication number: GB2068546A
Application number: GB8101551A
Authority: GB
Original assignee: Teldix GmbH
Current assignee: Rockwell Collins Deutschland GmbH
Priority date: 1980-01-17
Filing date: 1981-01-19
Publication date: 1981-08-12
Also published as: FR2474162B1; DE3001482A1; FR2474162A1; DE3001482C2; GB2068546B

Abstract

A method of changing maps in a vehicle-position indicating device (1) which has a follow-up computing device for calculating the position coordinates of a vehicle provided by a navigation system, and an indicator 9 indicating the position of the vehicle on the map, comprises coding a chosen respective reference point on each of the successive maps through the regions of which the travel path of the vehicle extends, setting this reference point on the changed map against a predetermined position (6) in the device and feeding the coded coordinates of the reference point to the computing device so that the computing device can set a movable indicator (9) to the position on the map which coincides with the vehicle position. A means for correcting any misalignment between the reference point and the predetermined position is described. <IMAGE>

Description

SPECIFICATION A Method of Changing Map Regions In A Map Device The invention relates to a method of changing the region of a map placed into a map device, in which the map device has a follow-up computing device which calculates, from the co-ordinates of the vehicle provided in each case by a navigation system, the point within the region of the map placed in the map device is to be indicated and which corresponds to these co-ordinates. This computing device actuates a circuit for driving a movable indicator for the purpose of appropriately setting it.

Usually, in map devices, several separate but successive or slightly overlapping maps maybe used; when the edge of a map is reached the map is changed and the movable indicator of the map device then has to be displaced by the width of a map or the height of a map in order to arrive at the correct new setting for the indicator. No account is taken of the path which has been travelled after the indicator reaches the edge of the map in this method; in order to achieve this, there are solutions which are known which need not be dealt with here.

In order to use ordinary maps which can be folded or divided up, it seems desirable to so form the map device that the map can be made suitable for placing into the map device by folding, only a part of the whole of the map being visible in the window of the map device. For this purpose, a part of the map device which contains displaceable indicated lines and which can be raised is provided; the map is placed between this raisable part and the baseplate of the device and is clamped there. This makes it possible to bring any desired portion of the map into the window of the map device. In order to do this, it is necessary to give the computing device a reference to the map and to align the map so that its co-ordinate grid has a certain predetermined alignment.

If a predetermined journey or flight is to be made, for example say diagonally within the map, it is more suitable to use a map which can be displaced as desired rather than to use individual maps, because the regions of the journey or flight which are to be placed in the map device can be matched up more easily.

The invention seeks to make it easier to insert these map regions.

According to the invention, there is provided a method of changing map regions in a map device having a follow up computing device which calculates from location co-ordinates of a vehicle provided by a navigation system the point within the map region which corresponds to the location co-ordinates and is to be indicated; wherein, when the travel of the vehicle is provided in successive map regions, a reference point on the map regions is coded and stored, the reference point on the map region is set in a predetermined positional relationship in the map device and the coordinate values of the reference point are provided to the corresponding device so that the computing device using the reference point information, can set a movable indicator to a position on the map region which coincides with the vehicle location.

It is simple to insert the regions of the map which will be required one after another by preselecting and coding reference coordinates on the map which lie within the region of the journey or flight, these coordinates being stored in a store.

The operator only has to place the appropriate region into the window of the card device and to make the reference coordinates coded on the map coincide, for example, with a fixed marking in the map device. Since the position of this indicator in the map device is available to the follow-up computer, after inserting the region of the map, the map coordinates of this indication are made available by the store, e.g. at the press of a button by the operator. Moreover if the actual coordinates of the actual location are fed to the computer by the navigation system, the computer is in a position to calculate the point corresponding to the actual location in the inserted region of the map and to so control the indicator drive circuit that the movable indicator of the map device is moved by the drive to the appropriate point on the map.Therefore, the operator only has to insert the map, align it and press a button in order to call up the reievant store contents. For example, only one of several keys associated with the individual stores have to be actuated or one of the code numbers (address) associated with the individual store has to be keyed in.

An alignment member, for example a clamping element, punched card or strip, may be fixed to the map so that the map is fixed with the aid of a mounting arranged on the map device so that there is a relationship between the map and the map device. This may be achieved by providing the alignment member with an indication and putting this indication into contact with a selected grid intersection point so that, by inserting the coordinate values into the store before the start of the journey or flight, this value only has to be called up when inserting the map and the association between the movable indicator and the portion of the map is made automatically.

If a clear film etc. which can be adhered to the map is used as the alignment member, and the film is provided with associated holes or apertures, then it is also possible to arrange several of these alignment members on different portions of the map and depending on the pdrtion selected, the apertures may be brought into connection with pins arranged on the map device.

The map has to be brought into a relationship with the map device and in this case coordinate intersection points are stored depending on the number of alignment members and the appropriate coordinates can be called up depending on the portion of the map being used.

The coordinates of the grid intersection point may be coded, the alignment member being related to the grid intersection point, so that the coordinates can be detected with the aid of a coding arranged on the alignment member, when inserting the card by means of a scanning device and the movable marking can be associated with the card without manual input. The said coding may be effected by means of known line coding or hole coding, in which the holes are either mechanically scanned with sensors or scanned optically.

The invention will now be described in greater detail by way of example with reference to the drawings in which: Fig. 1 shows one embodiment of the invention; Fig. 2 shows a graph designed to explain other embodiments; Fig. 3 shows a possible arrangement of a map in the map device.

In Fig. 1, an embodiment of a map device in accordance with the invention is shown. Fig. 1 a shows a plan view and Figure 1 b shows a side view of the device from which it is apparent that a part 2 which carries two indicator strips 4, 5 which are displaceable by cord drives, can be raised with the aid of a hinge 3 and a conventional map can be placed between the baseplate 1 and the raisable part 2. A fixed indication is indicated at 6. 7 is a display device and 8 is an operating device.

Before the start of the journey, the navigator searches for various easily read-off grid intersection points in the area of the map over which it is intended to travel and marks them, by giving them a code number for example. In order to store the related coordinates, the key with the additional designation NO is pressed, and then the code number is keyed in with the aid of the operating device 8. After actuating the key ENT because the letters E and N have appeared on the display device 7, the north and east value of the coded grid point have to be put in and stored (ENT) in the store selected by the code number.

During the journey, as the edge of the region of the map which is inserted is approached, the map is changed in accordance with the next part of the journey, the marked grid intersection point of the next region of the map to be used being made to coincide with the indication 6. After pressing the key NO and feeding-in the related code number, the coordinates of the point on the map lying beneath the indication 6 are fed to the computer.

Since the computer knows the position of the fixed indication 6 and the position of the indicator 9, the actual coordinates of the vehicle are fed to it and it has a map reference based on the coordinate values, which come from the store, of the point on the map lying beneath the indication 6; it is able to implement displacement of the indicator 9 so that the appropriate location on the map is indicated.

It is possible to make it easier to place the map into the map device correctly if the coded grid intersection point has to coincide only approximately with the fixed indication. However, it is then necessary for the adjustable indicator of the map device to indicate this fixed indication, i.e. when the command to change regions of the map is fed in, it moves to this particular point.

The method in accordance with the invention will be described in greater detail with reference to Figure 2. There, the window of the map device is designated 20. The position 21 corresponding.

to Figure 1 is not coded by a fixed indication but rather by a settable indication; the indication is formed - as in Figure 1 - by the intersection point of the adjustable lines. On the command being given to change maps, the intersection point of the lines moves automatically to point 21, by appropriate control of the drives of the lines. The new map region is then placed into the map device. When using this modification of the method, it is sufficient if the marked grid intersection point is made to approximately coincide with the point 21.

In Figure 2, 24 is the indicated grid intersection point and 24a and 24b are the related grid lines.

By actuating the drives for the lines 22 and 23, the lines are set to the point 24 by moving distances of Ax and Ay. Therefore the intersection point of the lines is made to coincide with the indicated grid intersection point 24. The amounts of adjustment Ax and Ay are stored in the follow up computer. When subsequently calcuiating the setting of the lines for the purpose of displaying location these amounts of adjustment have to be taken into account. In other words: a map reference point does not have to be brought to a certain point on the card device, instead its deviation from this point is determined and taken into account.

As a result, it is much easier to insert the map particularly if the operator only has one hand free.

The correction stated above is sufficientif the map is aligned, i.e. the grid line 24b is parallel to the thread 22 for example. If the map is rotated by the angle P as is assumed in Figure 2, then an additional correction has to take place. In order to do this, the thread 22 is provided, for example, with a marking 25 or 25' which lies at a predetermined spacing from the point 2-1. The thread 22 now has to be displaced by the path As until its marking 25 lies on the grid line 24b (at 25').

from the relationship: As tg(p= l+Ay or the approximation: As since (p 5 small and l Ay P-- I (p can be calculated and taken into account when setting the lines for the purpose of displaying location. Instead of a marking on the thread 22, the lines 23 may also be moved downwards by the path I and thus find the point 25 to which the line 22 has to be set. Instead of providing the marking 25 or 25' on the thread, a marking can be provided on the grid line 24b (this is assumed to be identical to 25') which lies at a known spacing I' from the marked grid intersection point 24. This marking can be given by another, e.g. the next, grid intersection point.The thread 22 is now displaced by a distance As from the position in which it passes through the point 24 until it passes through the marking 25'. From the value determined for As and the known magnitude of 1', P can now be calculated as follows: sInce (p As As or (p (since (p iS small).

I' I' The basic method of the invention provides for several points to be marked on the map and their coordinates to be stored. The correction processes can of course be used in conjunction with the basic method. However, they can be used in the same way if the change of maps has not been prepared, i.e. if no grid intersection points have been coded or if their data has not been stored; if a grid intersection point has only been selected when exchanging maps and its data has to be fed in first of all.

Fig. 3 shows a folded map 33 which is suspended from pins 27 of the map device 1 (only partly shown) with the aid of a film 26 of which has a part has been adhered to the map and a further part (not adhered) has receiving apertures 28.

A further film 34 is adhered to the map 33, the films 26, 34 having marking arrows which are aligned with grid intersection points. Moreover, the coordinates of the related grid intersection points 29, 35 are applied to the films 26, 34 in coded form. A scanning device 31 is arranged between the pins 27 of the map device 1.

If the map 33 - as shown in Fig. 3 - is placed into the map device, the scanning device 31 detects the grid intersection point 29 with the aid of the coding 30 of the film 26 or it detects its coordinates and passes these to the computer which subsequently displays the actual location on this portion of the map with the aid of the movable indicator. If the location changes and moves into the lower region of the map, or moves downwardly over the portion of the map which is shown, the map 33 may be taken out and folded near the folding line 32, the map 33 then being fixed to the pins 27 with the aid of the film 34 which sticks to the map only with its lower half. If the map comprises individual sheets or pages, the computer determines the next sheet or page of the map which is required by comparing the coordinates and shows the number of this sheet or page on the optical display. As a result, when using individual map parts, the visible part of the map can be changed safely and rapidly. The scanning device 31 subsequently determines the coordinates of the new grid intersection point 35 by means of the coding 30 of the film 34 and the movable marking follows on the manner described above.

Claims

1. A method of changing map regions in a map device having a follow up computing device which calculates from location coordinates of a vehicle provided by a navigation system, the point within the map region which corresponds to the location coordinates and is to be indicated, wherein, when the travel of the vehicle is provided in successive map regions, a reference point on the map regions is coded and stored, the reference point on the map region is set in a predetermined positional relationship in the map device and the coordinate values of the reference point are provided to the computing device so that the computing device using the reference point information, can set a movable indicator to a position on the map region which coincides with the vehicle location.

2. A method according to Claim 1, wherein a fixed marking in the map device is made to coincide with the coded reference point.

3. A method according to Claim 1, wherein an alignment member attached to the map and having a certain position with respect to the reference point is brought into alignment with a mating element arranged in the map device and the map is fixed in a predetermined position by this alignment.

4. A method according to Claim 3, wherein aclear film which can be adhered on to the map is provided as an alignment member and at one non-adhered part of the alignment member, it has receiving apertures and is placed into the map device so that pins-arranged in the map device engage in the receiving apertures and fix the map.

5. A method according to Claim 3 or 4, wherein the reference coordinates are arranged on the alignment member in the form of coding, and a scanning device in the map device scans the coding either while or after the map is placed into it and supplies the reference coordinates to the computing device.

6. A method according to any one of Claims 1 to 5, wherein the fixed indication is formed by the movable indicator of the map device, which indicator moves towards a certain point when the map region is changed, the coded grid intersection point on the map is brought more or less into alignment with this point, the indicator of the map device is adjusted thereafter in the direction of the coordinates by lengths of +Ax and +åy so that the indicator and the grid intersection point coincide and the adjustment paths required (+Ax and +åy) are detected by the follow-up computing device and are taken into account during subsequent setting and follow-up of the indicator.

7. A method according to Claim 6, wherein if the map is at an inclined angle in the map device, this angle is taken into account by adjusting the indicator in a predetermined coordinate direction until a point offset in the other coordinate direction in the extension of the indicator and offset by a predetermined spacing with respect to the fixed indication coincides with the related grid line which passes through the coded map point and from this known length I and depending on the coordinate direction of the length +Ax or +åy which has been selected, the angle of rotation (p of the map is determined in accordance witn tne following relationship: As As tg(p= or l+Ax IlAy or in accordance with the following approximation:: As (since (p 5 small and Ay l) and this angle is taken into account when calculating the setting and follow-up for the indicator.

8. A method according to Claim 6, wherein an inclined position of the map in the map device is taken into account by adjusting the indicator in a predetermined coordinate direction for a distance As until a point which lies on the grid line in the other coordinate direction and is at a distance of a predetermined length I' from the coded grid intersection point is made to coincide by extending the indication in the x- or y-direction; and the angle of rotation so is determined from the magnitudes I' and As in accordance with the following relationship: As As sine (p= or the change in = I' I' and this angle is taken into account when calculating the setting and followup for the indicator.

9. A method of exchanging map regions in a map device substantially as described herein with reference to the drawings.