FR2625576A1 - METHOD FOR REPRESENTING A ROAD NETWORK IN DATA MEMORIES - Google Patents

Abstract

a) Method of representing a road network in data memories. b) Method characterized in that: - each lane 23 of the representation of the road network is assigned a distinctive sign which is deposited in the data memory, - from a collection of data for each lane 23 of the representation of the road network, the coordinates of these support points 24 are successively called, - the data of the support points 24 assigned the smallest and largest address number are called first and stored, - the coordinates of the other support points 24 of the track are called successively in a progressive manner and their distance from the straight line is determined, only are stored, as essential data, the data of the support points and the distinctive sign of the track which have been stored. found as starting and ending points. c) The invention relates to a method of representing a road network in data memories.

Description

Method of representing a road network in

data memories. "

  The invention starts from a method for determining

  the essential data of a representation of a road network and to introduce and store them in a data memory, which is used in a vehicle, with a dead reckoning, for

find a goal called.

  In the BOSCH Technical Reports, volume

  8/86, issue 1/2, pages 61 to 65, is described a

  process for digitizing and memo-

  representation of road networks for

  an autarkic locator system for vehicles

  intervention vehicles, such as police vehicles

  this, firefighters and the like. In this document, the road network representations are stored in a memory array on a two-dimensional frame representation by binary combinations.

  appropriate, such representations being, for example, ob-

  held by optical scanner scanning from a

  city map or topographic sheets. se-

  the density of streets or roads, the weft is then chosen so that, on the one hand,

  memory are limited, and that, on the other hand,

  stored binary pattern allows an assignment

unequivocal streets or roads.

  This method has the disadvantage that for the digital formatting of a city map, important storage means must be implemented. In addition, the data of city plans must then be almost in all cases, read again, before they can be stored in digital form, because the representations of the cities plans that can be exploited by calculator, or do not exist, or can not be

  obtained because of requirements concerning the

  tection of data. Another disadvantage is that such a representation of road networks does not provide for the assignment of address numbers along the tracks, so that the introduction of purpose addresses in the form of routes and numbers Address

  not possible; With the esteem navigation

  nue, only accordingly, the respective location of the vehicle is indicated by the representation of the network

road and memorized.

  In another method known from WO 86/01442 for determining, introducing and

  memorization of locations and goals in a

  of navigation data, the Polish coordinates

  points of departure and arrival are determined with a special measuring device

  and are introduced at the same time as the

  scale of the map, via keys and

  in the corresponding memory of the calculation

  navigator. During navigation, the

  and the distance from the point of arrival called, are

  respectively indicated by the esteem navigation.

  However, this solution has the disadvantage that in the determination and introduction of

  points of departure and arrival by means of their

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  Polar data, we must proceed with great care. As in addition, during the introduction of the goals, the corresponding address can often not absolutely

  not be obtained from street or street plans.

  can only be approximately

  such aims can not be introduced in a pre-

  cise, or to be approached precisely by navigation

esteem.

  With the present invention, it is sought to

  cilitate the navigation for vehicles by calling the track and the address number of the starting point and

  the point of arrival, by determining from

  halogen data, essential data for

  representing a road network and memorizing them

  risking in a data memory of a system of

vigation.

  The process according to the invention is

characterized in that

  a) to each channel of the representation of the road network

  tier is assigned a distinctive sign that is deposited in the data memory, b) from a data collection for each pathway

  representation of the road network, are suc-

  terminally called, by an address number which

  associated with them, and as material for

  the points of support, such as centers of gravity of dwellings, distribution and similar connections, and

  channel data is memorized intermedia-

  (c) the data of the number of

  the smallest and largest addresses are called

  firstly and intermediately stored as the initial point and the end point, and a line is drawn between this initial point and this end point, d) the coordinates of the other points of support of the

  path are successively called progressively

  sive and their distance from the right is determined, e) the largest distance respectively determined is compared with a predefined limit value, f) in the case where the greatest distance from the fulcrum

  is less than the limit value, only the

  number of points of support assigned to the number of

  the largest and the smallest are memorized, with the distinctive sign of the way, as

  essential data, all other points of

  (g) In the case where the greatest distance from the fulcrum is greater than the limit value, this fulcrum is memorized in an additional intermediate way as a new point. terminal, a new line being drawn between it and the affected point of the smallest address number and acting as an initial point, and another line drawn between the new terminal point and the affected point of support of the highest address number and acting as a previous endpoint,

  h) steps d), e), f), and g) of the process are repeated

  for each new straight line, until all distances from the initial point to the

  end point of each of the lines are less than

  above the predefined limit value,

  i) only are stored as essential data.

  tial data, the data of the fulcrums and the lane sign that were found as

initial and terminal points.

  The process according to the invention has the advantage that taking into account the requirements of

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  protection of data, from halogenated data stocks, points of representation of road networks, such as, for example, the coordinates of residential centers of gravity, distribution connections, water intakes, shut-off valves water and gas and the like, be treated in such a way that

  these data are associated with pathways and nu-

  meros of determined addresses. In addition, thanks to the

  according to the invention, the quantities of data to

  memorize are reduced so that the means of

  necessary moralisation be covered even for

  representations of road networks of major cities

  by semiconductor memories,

  cartridges, tapes, CD plates and the like, which can be housed in a navigation system of a vehicle. As another benefit, it is worth considering

  with the data so obtained from the representative

  In a road network, reliable navigation is possible to find arrival points, since departure and arrival points are defined by routes and address numbers and can be

introduced appropriately.

  According to another characteristic of the invention

  the distances from the points of support to the straight lines are gradually determined from a

end of the way.

  According to another characteristic of the invention

  tion, the distances from the points of support to the lines are gradually memorized intermediately

  and compared with the distance from the fulcrum

  until the distance decreases, and the greatest support distance is then

  compared with the predefined limit value.

  According to another characteristic of the invention

  In the case of track layouts for which more than two support points have been obtained, from three successive points of support the distance between the

  median point of support and a straight line through the first

  and the third fulcrum is determined, and this distance is compared with a predefined value

  limit, and in the case where this distance is

  below the value of the limit, the fulcrum is removed for the smoothing of the track layout and

  is not taken into account in the data memory.

  According to yet another characteristic of the invention, for smoothing the path of the track, the

  first three points of support are first called

  that then progressing from one point of

  three other points of support are called for

  route, and these steps continue until the last point of support for the

be apprehended.

  According to yet another characteristic of

  invention, in the case where the distance from the point of ap-

  The median strength of three successive points of support is

  than the value of the limit, this point is sup-

  awarded in the immediately following succession of

  three points of support and is no longer taken into account.

  Finally, according to another characteristic of the invention, the various stages of the process are

  treated for each channel in the representation

  road network by electronic processing.

only data.

  An exemplary embodiment of the invention is shown in the accompanying drawings and exhibited further in

  detail in the description below:

  FIG. 1 is a functional diagram as a function of the procedure of the method for obtaining the essential data of a channel plot; FIG. 2 is a functional diagram as a function of the call for intermediate storage of the data of a channel; FIG. 3 is the representation of a track with housing centers of gravity as support points of the track; FIG. 4 is a functional diagram for the weighting of the support points of the track lying all close to each other - Figure 5 shows the support points of

  the path of Figure 3 with a rectangle

  which is divided into sub-rectangles; FIG. 6 shows a reduced number of support points of the track of FIG. 3 with sub-rectangles on a larger scale; FIG. 7 shows the support points of FIG.

  the path according to Figure 3 left aside by a dou-

  FIG. 8 is a functional diagram for the linearization of the representation of the channel, FIGS. 9 to 15 are the representation of the channel support points with different parts of the linearization, FIG. the representation of the channels by a polygonal line after the linearization, - Figure 17 is a block diagram for the smoothing of the representation of the tracks, - Figure 18 is a block diagram of a navigation system in the motor vehicle, - Figures 19 and 20 are diagrams

  functionalities for the introduction of departure and

  riveted in the navigation system.

  FIG. 1 is a functional diagram showing the progress of the process for

  get the essential data for a way to

  from a halogen data store of a topo-

  graph, this stock including the coordinates of

  centers of gravity of dwellings on the chosen lane

  sie. We then start from the fact that for navigation se-

  data from the city plan, a database of

  is necessary, in which must be contained a representation as simple as possible of the plan of the city. Data must be in an understandable form for the navigation system

  and be easy to handle. For each individual route

  duality, it is necessary to have information from which the layout of the track, its position

  geographical location and information on the

  number of addresses along the way,

come out in an appropriate form.

  Information about address numbers

  existing in the track must allow a conclusion

  feedback on the position of a given number inside the lane. In the case of short ways or places, the address number is, in principle, of little importance, because one can, in this case, that to arrive to find anyway the way or the place. But more importance attaches to address numbers

  when in paths of great

  a particular point must be addressed. As

  in almost all German surveying services

  mands exist for the areas they have taken

  the collection of data concerning the centers

  properties and dwellings, these areas are particularly suitable for obtaining

  essential data of red network representation

  tier for navigation. For each of the channels in the representation of the road network, the process steps shown in Figure 1 and described in more detail below, are successively processed in an electronic data processing installation.

  After starting 10, for a chosen path

  In this case, the centers of gravity of dwellings on this path are, in a first step 11 of the method, called from the halogen data collection and memorized intermediately. In

  step 12 of the process, the centers of gravity of

  close to one another, are weighted to obtain a common center of gravity,

  so that some of the initial data is deleted.

  nted. In step 13 of the method, the entire path of the path is linearized into one or more rectilinear partial expanses, insofar as all the dwellings within a predefined bandwidth are located next to each other. the linearized route of the route. Initial and terminal points of

  rectilinear partial expanses are memorized

  intermediate point and the other intermediate points

  are deleted. In step 14 of the process, two

  Partial linearized partial values are then smoothed to form a new common partial extent if this new partial extent, which lies between the two end points of two partial extents hitherto neighboring, does not exceed

  a determined distance from the intermediate point

  common to both extant neighboring areas. In this case, the point lying between these two partial expanses lying one behind

  the other is also erased. In step 15 of the pro-

  given, the remaining points of support are then

  in the data memory of the

  with their coordinates and the numbers of

  dresses associated with them at the same time as with the distinctive sign of the way. In step 16 the program is stopped. The same process is repeated

  then for each of the other ways of representing

  road network, until all

  have been apprehended and that the essential data

  the ones for their representation have been deposited in the data memory.

  With the help of the following figures, the differences

  the steps of the process of Figure 1 will be ex-

  in more detail, from a data collection

  born, with the coordinates of the centers of gravity of the dwellings. Figure 2 is a functional diagram for the call of the coordinates of the centers of gravity of the houses, for their conversion into successions

  increasing numbers of addresses and for their memo-

  intermediate implementation. After startup 10, it is first selected in step 17, from the stock

  halogen data, a way from the repre-

  the road network to memorize. This lane is then assigned a distinctive sign, for example a number of four digits, which will subsequently be taken into account in a nomenclature of roads of the representation of the road network for the introduction of departures and arrivals during navigation. This

  distinctive sign which increases with each new

  called, is then stored in step 18 for the chosen channel. In step 19, data from

  dwellings of this road are then called success-

  from the data store by number of

  dresses croissants. For each dwelling, three blocks

  data are then memorized intermedia-

  re, the first block containing an address number of

  three digits. The second block contains the coordinates

  X coordinates of the center of gravity of the dwelling, and the third block the coordinates Y. As the coordinate values, for example in a known manner as Gauss-KrUger coordinates, lie in a system of orthogonal coordinates with the equator

  as a reference axis and require many locations

  memories, these coordinates are converted in step 20 into a coordinate system with a reference point within the representation

  of the road network, for example the lower left corner

  the representation of the road network. The coordinators

  data thus converted from the center of gravity of the

  bitations, essentially require only a few memory locations. The conversion can be performed in a particularly simple way when the

  new reference point with its Gaussian coordinates

  Kr ger can be taken from the donor material

  born. In this case, the difference of the X and Y coordinates of the centers of gravity of the dwellings in relation to

  the new reference point, are respectively

  nted. In step 21, the data thus obtained from all dwellings of the called track are then

  memorized intermediately with the number of

  draws up to constitute what are called the points

support of the track.

  In Figure 3 is shown the outline of

  do not see 23 with dead ends starting from this lane in a limited area of the road network representation to be memorized. In this figure are furthermore represented, with their address numbers, all the support points 24 memorized intermediately in the part of the method according to FIG. 2, points from which, with the method according to FIG. essential for the representation of the network

  will be obtained. It is then necessary to remark

  that apart from the number of points of support 24 with their coordinates, there is no other information

  available with regard to the track. The route is

  fictitious. the route, which has been indicated, does not need to be taken from the halogen collection of data. It can be at most tipped, from the position of the centers of gravity of the dwellings

  and distribution, address numbers.

  Figure 4 is a functional diagram with which, by weighting the centers of gravity of houses placed close to each other, the number of support points for the track is reduced. After the start of this part of

  program according to Figure 1, are first detected

  intermediate, in step 26, the most

  outside. With these points of support, then is con-

  staged, in step 27, a rectangle in which the

  X or Y coordinates of these points of support, are collected

  to form the coordinates of the corners of the rectangle. In FIG. 5, this rectangle, which includes all the support points 24 of the track, is designated 36. In step 28 in FIG. 4, the rectangle 36 defined by the memorized angle points is divided into a plurality of sub-rectangles 37. The number of these sub-rectangles 37 is then determined by the number of support points 24 per lane. It turned out

  advantageous, as regards the number of sub-

  rectangles 37 per side of the rectangle, divide the

  number of points of support 24 by the number 4 and

  round up the result up or down.

  This subdivision for the track according to the

  Figure 3 is shown in Figure 5. In the case of this example, there are 33 points of support of the total track, a subdivision of the rectangle 36 8.x 8

  sub-rectangles 37. These sub-rectangles 37 are also

  stored in an intermediate way with their coordination

  data. points of angles. Such subdivision shall, however, be carried out only for lanes with a minimum number of dwellings, for example at least 14 dwellings. In step 29 of the functional diagram of FIG. 4, it is checked accordingly whether the rectangle 36 in the previous step 28 has been subdivided into more than 9 sub-rectangles 37.

  is actually achieved in the case of the present

  ple, all the sub-rectangles 37 are successively checked in step 30 to know if, in one or more of these sub-rectangles 37, there are two or more points of support 24. If this is the case, the coordinates of the bearing points 24 concerned with such a sub-rectangle, are weighted in step 30 and, at

  from there, a center of gravity is made up of

  which is assigned one of the address numbers of the points

  weighted and this number is then

  mediated with the coordinates of the center of gravity. The support points considered until now in this sub-rectangle can now be erased. It may then be advantageous to assign to the center of gravity the address number of the

  fulcrum 24 closest to him.

  In the case of the example according to FIG. 5, in five of the sub-rectangles 37, five gravity centers 38 have been formed by weighting which have been memorized, whereby six points of support 24 can

  to be erased. In step 31, the number of sub-

  rectangles on each side of the rectangle, is then

  covered by 2, that is to say that the surface of

  rectangles is increased by the multiple 4. It is indicated in FIG. 6 that henceforth the rectangle 36 has been subdivided into 4 × 4 sub-rectangles 37a. In step

  32 of the functional diagram according to FIG.

  control then again if the number of sub-

  rectangles 37a thus formed is greater than a number of 9 sub-rectangles. As is the case with the present example, all sub-rectangles 37a thus enlarged are then checked successively in step 33 to find out if there are more than two

  24 points in one or more of these sub-

* rectangles 37a. External support points determine

  born in step 26 are then not taken into account.

  In step 33, the coordinates of all the support points 24 which are

  included in a sub-rectangle 37a. Thanks to this

  6, each of which is assigned in the case of the present example, the smallest address number of the points of support contained in the sub-rectangle 37a, is formed in accordance with FIG. corresponding. These centers of gravity 38 are memorized intermediately in

  as new points of support with the numbers of

  which are assigned to them and with their coordi-

  17, until now considered sub-rectangle 37a, can be erased. Figure 7 shows the relatively uniform new distribution of support points after double weighting. The remaining initial support points 24, as well as the centers of gravity obtained by weighting, are then deposited in common in a data memory during step 34,

  as support points for the track, with their coordination

  data, with the address numbers assigned to them.

  as well as with the distinctive sign of the track.

  This deposit includes at the same time, the four external support points of the track, which were left aside during the weighting during step 30 and

  from step 33. In this way, by taking account of

  data protection requirements, obtained

  from a halogen collection of data, with the centers of gravity of one-way dwellings,

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  essential data for this route, data which make it possible, by introducing a

  address and an address of arrival in

  distinguishing the distinctive sign of the track and the address number, to achieve in a system

  esteem navigation, pre-navigation

  cis as to the goal to be achieved. The need for means of

  memory in the data memory of the navigation system

  in this case, are considerably reduced in relation to the need for memory

Halogen collection of data.

  When determining points of support according to the part of the method according to FIG. 4, it is important that the number of sub-rectangles, during the first subdivision of the rectangle 36 containing all the points of support, is rendered depending on the number of

  support points 24 of the track. In the case of a repair

  relatively uniform dwellings along the road, it may occur that in step 30 no sub-rectangles 37 are found which contain

  more than one fulcrum 24. In this case, the enlargement

  sub-rectangles 37 in accordance with step 31 is immediately performed. These process steps are

  then repeated until a formation of cen-

  very serious or until the number of sub-rectangles is reduced to nine. If it is already the case in step 29, no weighting

  is not performed. The program then jumps immediately

Step 34. In order to find the beginning and the end of the track, in step 4 of

  block diagram of Figure 4, the numbered bearing points 24 assigned

  the highest and the smallest addresses are

  also stored with their coordinates as fixed points of support for the track and in view

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  additional treatment, or they are

  as essential data of the channel in the data memory. In the case of this example,

  the number of points of support 24 is reduced by the

  33 to 17. As a variant of the functional diagram of FIG. 4, it is possibly advantageous that, in steps 26 to 34, only the affected support points

  even address numbers are first called

  stored in an intermediate way, possibly reduced

  in centers of gravity in the sub-

  rectangles, and stored with the address numbers that are assigned to them. Then, the same steps of the process are carried out with the points of support of the

  track that carry an odd address number. Well

  Tense, the flow can be reversed starting with odd address numbers and ending with * even address numbers. In the formation of sub-rectangles 37, 37a, the number of the fulcrums of a channel is decisive. For the number of sub-rectangles 37 to be formed for each side of the

  rectangle 36, containing the points of support 24, the name

  number of points of support 24 must be divided by a

  tiple of 1. In the case of a small number of

  points of support, it should be divided by 2 or 3.

  For a very large number of housing support points

  it is advantageous to repeat the

  enlargement of the sub-rectangles 37 as well as the

  and intermediate storage, according to steps 30 and 33 of the functional diagram of Figure 4, until we obtain for each channel, 3 x 3 sub-rectangles.

  If for a lane, there must be relative

  few centers of gravity of dwellings as points of support, it is advantageous when

  the formation of sub-rectangles 37 to choose the name-

  sub-rectangles for each side of the rectangle so that in none of these sub-rectangles

  have more than one fulcrum. Then, the sub-

  rectangles can be enlarged until in one of the rectangles there are two points of support from which a new center of gravity is

  then formed by weighting. After this first

  With a center of gravity, the sub-rectangles are enlarged again until, in another sub-rectangle, there are two points of support. These also are then gathered by weighting for

  constitute another center of gravity and are

  in the case where the number of

  minimum of 9 sub-rectangles is not yet reached.

  The enlargement of the sub-rectangles can not, of course

  to be repeated several times. However, to avoid

  thus to a too important distortion of the points of support, the weighting and the formation of

  centers of gravity should be limited to a maximum of

two operations.

  Another reduction of the points of support of a track is obtained by a linearization of the route of the track, which is carried out in part 13 of the diagram

  according to Figure 1. This part of the procedure

  is connected to the process for weighting and

  Formation of the centers of gravity according to Figure 4.

  During linearization, the channel support points obtained in the previous part of the process,

  must be reduced in a complementary way. We imagine

  First of all, to join together by a polygonal route, the existing points of support in increasing or decreasing successions of the address numbers assigned to them, this polygonal trace being then replaced by a simpler one. This polygonal route more

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  simple is then examined to see if it describes

  sufficiently precise the polygonal layout predefined

  nor existing points of support. If so, the

  simple polygonal layout, that is, the points of

  connected by it, is directly used and the other points of support are eliminated. If, on the other hand, points of support are too far removed from this simplified polygonal layout, this one is widened and compared again

with the support locations.

  Figure 8 shows, in a functional diagram,

  tional part of the method for linearizing the representation of the track on the basis of the support points 24, obtained in FIG. 7, of the track 23 of FIG. 2. After the starting 40, is firstly called and memorized as a starting point in step

  41, the assigned fulcrum of the smallest number of

  among the existing support points 24 of the

  way. In step 42 we examine whether for the so-called

  There are several points of support. If this is not the case, it must be a square or a very short lane, which is characterized by only one dwelling. This fulcrum is then deposited in the data memory as a single fulcrum of the channel and the program in step 43 returns to the main program. If, as in the present case, it

  There are several points of support 24, the point of support

  number of the largest order number, is then called

  in step 44 and stored as a final point

  nal. Another part of the process is then exposed with the aid of FIG. 9. In this figure, the starting point has the address number 3 and the end point the address number 35. In the step 45 a straight line A is mathematically drawn between the starting point and the end point. In the next step 46, starting

  starting point, the point of support to which

  the highest address number coming from the following

  te, is called and, in step 47, the distance

  pendicular from this point to the line A is measured and memorized in an intermediate way. In step 48, it is checked whether the end point of line A is at-

  complexion. As long as this is not the case, the point of

  assigned the next highest address number, is called in step 46 and again its

  distance to the right A is measured and stored in

  intermediate step in step 47. If, finally, the end point is reached on this line, the fulcrum having the largest distance stored intermediate to the line A is called and in the case of the present for example, it is the fulcrum with the address number 15 whose perpendicular to the line A is represented in dotted lines. This distance b is then compared in step 50 with a predefined limit value a which constitutes a zone of tolerances on the left and on the right of the line A. This limit value is, in

  the case of the example shown, predefined at 40

  very. If all the points of support are within the

  within the zone delimited by this limit value to the left and to the right of line A, the route of the

  way, thanks to this line A, is considered as suf-

  well linearized. In step 51, it is checked whether the endpoint has the largest address number. If so, the starting point and the end point

  are delivered in step 52 as control points.

  the final route and in step 53 all

  other points of support are erased. The program

  then comes to step 54 in the main program

according to Figure 1.

  In the case of the example according to FIG.

  the distance b from the fulcrum having the number of

  15, is above the limit value

  predefined a. Now in step 55, the point

  used until then, ie the point of application

  then with the address number 35 is set aside and in step 56 the fulcrum obtained with the address number 15 is taken as a new end point, while via a loop 57, the

  program steps 45 to 50 are then again

  run, the line B being drawn at step 45 and at step 49, the fulcrum with the address number 8 being found as the one having the greatest distance from the line B. At the step 50, it is again found that this point of support with the address number 8 has a distance which is greater than the limit value a. Accordingly, in step 55, the endpoint previously used with the address number 15, is set aside, and in step 56, the fulcrum with the address number 8 is taken

  as a new endpoint. The course of the program

  me, through the loop 57 can then

to be done again.

  Figure 10 shows that, due to this new

  calf loop course of the program according to figure 8, it is found with the line C, in turn a point

  number assigned to address number 7, and whose

  to the right C is greater than the limit value

  predefined a. The program part, through

  of loop 57, should therefore be

  run again, the straight line D being formed. Again, the distance of the fulcrum with the address number 4 is greater than the limit distance a, so that through the loop 57 of the

  functional diagram, the line E is then formed.

  FIG. 11 shows that from now on the point of support remaining with the address number 3a has, relative to the line E, a distance that does not exceed

  the limit value has predefined. At step 51 of the di-

  functional gram according to FIG.

  the end point thus found with the address number

  se 4, is at the same time the largest address number of the track. As this is not the case in the example considered, the end point thus found is stored in step 58 and in step 59, this end point thus found is now set up as a new point.

  departure. In step 60, the end point set to

  tent last in step 55, is taken from the stock as a new endpoint, and

  through loop 61, the previous steps

  45 to 60 of the process are again traveled.

  In the case of the example under consideration, it is then

  As a new endpoint in step 60, the dot having the address number 7 and thus in the step, according to FIG. 11, the line F is formed. Here, too, the intermediate support points are within the limit value, so that in

  step 58 the end point with the number of a-

  7 is stored and in step 59, it is taken as a new starting point. The fulcrum with the address number 8 is called from the stock in step 60 as a new endpoint, and the line G is thus formed. In the same way, the line H is then found. Again, the fulcrum with the address number 11a is not outside the limit value, so that in step 58, the support points with the address numbers 8 and 15 are

  finally, also, memorized.

  As shown in FIG. 12, the point with the address number 35 is then taken as a new end point in step 60 of the functional diagram according to FIG. 8, and through the loop 61, the steps 45 to 60 are now traversed again as described until, in step 51, the fulcrum with the largest

  address number, is recognized as the endpoint.

  With regard to Figure 12, this means that with

  the right I, first of all the point of support with the nu-

  address maer 29a is found as a new ter-

  and then, the line J is formed between the

  new starting point and the new terminal point.

  Figure 13 shows that with the help of the line J a new end point, with the address number 20 is found, and thus the line K is established. Via the line K, the fulcrum having the address number 17 is then found and the line N is thus established. As between the starting point and the end point of the line L, there are no other points of support, the point of support with the address number 17 is stored in step 58 of

  functional diagram, according to Figure 8.

  Figure 14 shows that now between

  point with the address number 17 and the new

  calf terminal point taken from the stock with the

  address number 20, is placed the line M, and that

  be the starting point and the point of arrival of this line M, there are no other points of support, so that in step 58 the end point with the address number 20 is as soon as when stored and with the new terminal point taken from the stock and having the

  address number 29a, the line N is established.

  It can be seen from Figure 15 that

  of the N right, the point of support is

  killing outside the limit value a and

  as the address number 21, is found as a new terminal point which now forms with the starting point, the right O. As between the starting point and the ending point of the line O it does not there are no other points of support, the terminal point with the

  address number 21 is accordingly also,

  in step 58 and then form with the new

  terminal point 29a, the straight line P. As the fulcrum with the address number 21a is remote from the line P within the limit value a, the end point with the address number 29a is immediately when also stored in step 58. As new

  terminal point, the fulcrum with the number of

  35 is then taken from the stock and so

  the line Q is constituted. As in this case,

  the intermediate points of support do not cross

  the limit value a, this terminal point is

  nally recognized in step 51 as a point

  support assigned the highest address number.

  In step 52, the initial starting point, assigned the lowest address number, is transmitted to a

  data memory, as well as all the end points.

  stored in step 58, and in step 53,

  all other points of support are cleared.

  Figure 16 shows a polygonal plot of

  in this way between the points of support

  tants, with the partial segments or the sections of the straight lines E, F, G, H, L, K, O, P, Q. Thanks to this feature

  polygon, the route of the track 23 shown is ob-

  kept in approximate form. In step 54 of the functional diagram in FIG.

  accordingly, to the main program according to Figure 1.

  With this method, a straight path of the path obtained from the assigned center of gravity of the smallest address number and the assigned address number of the largest address number is first admitted and checked. if this route describes, so

  sufficiently precise, the positions of all the cen-

very gravity of dwellings.

  By this method, we first admit a rectilinear plot of the path between the center of gravity of the assigned dwelling of the smallest address number and that assigned with the largest address number, and we check if this route describes, in a sufficiently precise way, the positions of all the centers of gravity

  houses. If all the points are within the

  within the zone delimited by the predetermined limit value

  finished, left and right of the line thus obtained.

  naked, then the route of the path is defined in a sufficiently precise way by this line. But if, on the other hand, one finds, as in the present example, points of support which have a perpendicular distance - greater than the predefined limit value, the line obtained until now must be further improved by a polygonal plot. For this purpose, the fulcrum found to be furthest away is added to the new polygon layout and the process with the resultant sections or lines is repeated. Only the points of support which, according to their address number, are situated between the starting point and the point of arrival of the sections or of the respective straight lines are considered. In FIGS. 9 to 15, the various straight lines successively constituted, are represented by lines in solid lines, in

big dashes and small dashes.

  The final polygonal plot represented on the

  Figure 16 has only 10 points of support

  shown in Figure 9 which included 17. It is also

  possible to reduce the existing support point data for each channel from the halogen collection of data, without

  or the constitution of centers of gravity in the

  12 of the main program according to FIG. 1, by skipping the weighting method according to the functional diagram of FIG. 4. In the same way, a starting point and an end point are determined with the

  diagram of Figure 8, through

  the data of the points of support having the highest and the smallest address number of the channel, this starting point and this end point being deposited in the data memory and a line being then drawn between them. The coordinates of the channel memory points stored in an intermediate way are then successively called and the distance of these points of support to the right is determined. The largest distance found is compared with a predefined limit value. In the case where the largest distance of support points is less than this limit value, only the data of the points of support assigned the highest and the smallest address number, as well as the characteristic sign of the channel, are deposited in the data memory, all the other data points of support of the channel being on the other hand, suppressed. For the case where the greatest distance of support points is greater than the value

  limit, this point of support is memorized internally

  with its address number, as a new

  cal end point and between it and the fulcrum with the smallest address number, a new first straight is drawn. Between the new endpoint and the fulcrum with the highest address number so far, a new second straight is drawn. These process steps are then repeated for each new line until all the bearing point distances are smaller than the predefined limit value. The distances of the points

  support for the different rights, are then determined

  progressively born from the end of the track or

  well from a starting point or a point ter-

  minal. As a variant of the procedure of the method according to FIG. 8, a linearization of the channel represented with the aid of the existing support points can also be achieved by starting from the starting point the

  distances from the points of support to the right are progressing

  determined, memorized intermedia-

  and compared with the distance from the remaining fulcrum

  above, until the distance of the current fulcrum decreases with respect to the previous fulcrum. The largest distance of stored memory points is then compared with the predefined limit value. In case the distance from the point

  is less than this predefined limit value

  the distances of the support points continue to be determined progressively and compared

  between them until, after a further increase

  the distances of points of support, these

  grow again. The largest distance of support points found is then compared again with the predefined limit value. As soon as a support point distance is found, which is greater than the predefined limit value, this support point is memorized from

  intermediary way as a new terminating

  nal. The process steps are then repeated until all the points of support between the starting point and the new end point have a

  distance from the straight line at

  lower than the predefined limit value. The point

  thus obtained is now memorized as

  new starting point and all the points of support

  termediaries are erased. Between the new starting point and the end point of the track, a new

  right is now established, and the distances to this-

  the new right of the intermediate points of support,

  are again, in the manner previously described,

  between them and with the limit value

  defined. In this way, the layout of a track is

  presented in that for a predefined limit value

  for example 50 meters, the final points of support-

  stored in the memory are represented by a polygonal layout with straight sections to such an extent that the deviation of the support points thus found in relation to the actual layout of the track exceeds

worth the limit value.

  The part of the process described with the dia-

  functional gram according to FIG. 8, for the lineari-

  of the track layout, can also be achieved

  separately by means of support points with an even address number and support points with an odd address number. In navigation courses, we can thus find in better

  housing conditions on a lane with a den-

  very varied construction site.

  After the linearization in the part 13 of the main program according to FIG. 1 is completed, in part 14, the polygonal pattern obtained for the representation of the channel is smoothed and represented in FIG. 16. This part of the process is discussed in more detail in FIG. 17 using a functional diagram. After starting 62, we

  first check in step 63 whether for the

  of the way, there are more than two points of

  pui. If this is not the case, we can not perform a

  linearization because then, it is accepted that the way is

* Straight line between the two points of support which

  mark the beginning and end of this path. In con-

  sequence, in step 64, one returns to the main program according to FIG.

  for the representation of the track, three points of

  or more, the affected point of support of the most

  tit address number is then first called

  in step 65 and stored as a point of departure.

  part in step 66. On the representation of the track, according to Figure 16, this corresponds to the point

  with the address number 3.

  In step 67 is then called and memo-

  intermediately, the touchpoint assigned the address number immediately higher, in the case the address number 4. In step 68 is called

  stored as an end point, the point of application

  next, in this case, assigned address number 7. In step 69, a right is mathematically drawn between the starting point and the end point, and in step 70, the distance to the right of the intermediate point of support is measured. This distance is * compared in step 71 with a limit which in the

  case of this example, is predefined with 10 meters.

  If the distance thus determined from the mechanical fulcrum

  dian is not greater than the value of the limit, it proceeds between the starting point and the end point of the line, at a smoothing, in that in step 72, the median support point is therefore deleted and the

  endpoint is used in step 73 as new

  point of departure. If, on the other hand, the distance

  if determined from the median support point, as in the case of the example according to Figure 16, is larger

  than the predefined limit, then the

  dian is stored in step 74 as a new starting point. In step 75, it is then checked whether, beside the three points of support already detected, there are other points of support for the representation of the track. If it is, as in the present example, the case, then via a program loop 76 the new start point is again memorized

  intermediately in step 66, and the process

  described in steps 66 to 75 is repeated until in step 75 there are no further points of support of the track. In step 77, the first starting point, the last end point, and the starting points and intermediate terminals, are

  given as points of support for a representative

  now smoothed the track and in step 78,

  we return to the main program according to Figure 1.

  In the case of the example according to FIG. 16, it has no longer been found for a limit of 10 meters of support points which would have made it possible to reduce the

  number of points of support by the method of smoothing se-

  Figure 17. This must be attributed first

  that the actual route of track 23 is strong-

  bent. But in other tracks, some

  points of support can still be saved

thanks to this smoothing process.

  Starting from the halogen collection of data

  with the steps thus described of the process for a representation of a road network with a view to

  navigation, on the one hand, sufficient essential

  for the representation of the tracks are determined

  created and stored for navigation in a data memory, so that a purpose indicated by the channel and the address number can be found by a vehicle with dead reckoning. On the other hand, the data taken from the halogen collection of data are selected through the steps

  thus described of the process in such a way by weighting

  tion or formation of centers of gravity, by

  nearisation and smoothing, so that we can take

  account requirements for the protection of

  born, go back to existing data collections. The navigation system in a motor vehicle, known by the

  WO 86/07142, is not suitable for an application for the representation of a road network in a data memory, which have been obtained from a halogen collection of data, according to the method previously described. It must be completed or modified so that the

  memorization of the starting point and the points of arrival

  of a journey to be traveled, may be effected by

  troduction of the channels and address numbers corresponding to

laying eggs at these points.

  An introductory routine is needed,

  which can be called alternatively for the introduction

  duction of the distance and angle from the point of arrival. To this routine, the mission is to determine appropriate data for navigation from the values to be introduced for the route and the

  address number of the departure and arrival points.

  This is done using city map data.

  reduced in the form of channel support points that must be available for the system as a database in a data store, such as

  that read-only memory, floppy disks, circuit boards im-

prizes, cassettes or the like.

  To maintain the need for means of

  Morisation for the data of city plans within tolerable limits, we renounce to the introduction in clear text of the name of the ways. Instead, the channels are identified with a distinctive number assigned to them, which number can be taken from a list. Such a list is attached as

  software to the vehicle navigation system. The nu-

  The distinctive merits assigned to the channels can then be taken directly from the topographic service data files. If, on the other hand, the list of the lane names with the distinguishing number is filed together with the representation of the network

  in a data memory of the navigation system

  vigor, it is then possible, during the introductory

  departure and arrival points, to call the name of the route via a clear text The corresponding distinguishing number is then determined by the navigation system from

  from the list or from the stored data file.

  Figure 18 shows the navigation system of a motor vehicle, a system in which start and end points can be introduced for

  a navigation to find a goal. It is

  staggered by an input and output unit 80, a microprocessor 81 with a data memory 82,

  as well as by a route indicator 83 and an indica-

  the direction of travel 84. The micro-

  processor 81 processes the data from

  the path indicator 83, of the direction indicator

  84 as well as those coming from the operating keys of the input and output unit 80, and it also controls the output of data and

  direction arrows on a clear crystal display

  80 of unit 80. The operation of the

  navigation is performed using 5 service keys

  these. With a rocking key 86, numeric values

  The values can be changed up and down on diode 85. By pressing a confirmation key of order 87, the value is memorized.

  current digital display displayed on diode 85 which appears

  In the lower part of this diode 85, for example on a seven-segment, four-digit display 88. With a function selection key 89, the navigation system is switched in the context of a proposed menu. , in accordance with

  90 on the left border area of the uni-

  80, the information respectively displayed on the diode 85 being indicated by an arrow 91 of the

  diode 85 at the level of the inscription 90. Another

  key mutator 92 serves to turn on and off the navigation system. A seven-segment, two-digit display 93 in the upper zone of the diode is used to characterize 99 different allocations of goals or steps. A rosette 94 of the diode 85 with 16 different invisible arrow elements serves

  to provide directional information, the arrow of di-

  commissioned 95 representing either the direction of the north or the direction of the goal to be attained. Instead of the tilting key 86, it is also possible to use

  a keyboard for the introduction of numbers.

  The introduction of the point of departure and of

  will now be explained in more detail using

  functional diagrams of Figures 19 and 20.

  After switching on the navigation system by

  the key switch 92, the ENTER menu is selected

  selected by the selection switch 89 by pressing the selection key 89 repeatedly until the indicator 91 on the edge

  left of the display shows "ENTER". By a child

  short-term confirmation of the order confirmation key 87, the usual introduction known to the

  WO 86-07142, paths and angles with respect to

  port to the north between the point of departure and the point of arrival, is called. To arrive at the routine

  of introduction for routes and address numbers

  se, the command confirmation key 87 must be held down for about 2 seconds, until step number 93 starts flashing on the diode

  85. The desired mode of introduction is then selected.

  tioned. With the flip-flop 86, the step number to

  grammer can be modified. If the desired step is displayed, by pressing the command confirmation key 87, programming can be started. By

  depression of the selection key 89, the introduc-

  tion can be interrupted at any moment, and it

then appears the menu "NAVIGATION".

  In accordance with Figure 19, after the start

  96 of the introductory routine, it is determined in step 97 whether the programming is resumed or

  good if it is implemented for the first time.

  In this case, the system first requests, in step 98, the introduction of a starting point. In contrast to programming using paths and angles with respect to the goal, the introduction of a starting point is necessary to obtain a reference point for coordinates, reference point

  from which the system can calculate the coordinates

  orthogonal shapes from the data file in polar coordinates. If the order confirmation key 87 is depressed, the text "channel" appears on the display 88, by which the system requests the entry of the channel number. For the introduction

  number, the confirmation key

  dre 87 must then be pressed again. The navigation system predefined then from the memory

  82 with the representation of the road network.

  tier, the lowest channel number in the file of

  data. With the flip-flop 86, the desired channel number

  can be set up. That being done, the process

  by pressing the confirmation button

  87 must be completed. The introduction of the address number is then done in the same way. The lowest address number existing in the called channel is first predefined and can be changed with flip-flop 86. The system allows only numbers

  addresses that are between the address number

  the lowest and the highest of the appeals

  so that, in each case, the interpolation

  coordinates from the data of the points of ap-

  may be stored with the address numbers

assigned to them.

  If the correct address number is set up, this must be noted by pressing the order confirmation key 87. Then, it is carried out in step 99, with a sub-program according to FIG. 20.

  a conversion of the data introduced from the point of de-

  part in coordinates of this starting point, which is explained below below. After the introduction of the starting point, the navigation system requests in step 100 the introduction of an arrival point. We

  then proceed exactly, as in the case of

  troduction of the starting point, and in step 101 the coordinates of the end point are determined with the routine of Fig. 20 and stored. In step 102 we check if other points of arrival

  have yet to be introduced for other stages.

  By pressing the select key 89 in step 103, the introduction can be terminated. By embedment

  of the order confirmation key 87, other

  troductions of arrival points can begin.

  Figure 20 shows the flow chart

  for the determination of the coordinates of

  points of departure and arrival introduced. After the

  Marking 104 of the subroutine, the data set of the representation of the road network deposited in the data memory 82, is explored in step 105 to search for the introduced lane sign.

  or, possibly, the introduced path name.

  In step.106, we see if the path has been found

  35. vée. If it is not, this is indicated in step 107 via diode 85 and

  the introduction is stopped. It can be repeated se-

  In FIG. 19, if the channel has been found, the lowest address number of the stored memory points of this channel is called in step 108 from the data set, and is compared in FIG. step 109 with the entered address number. If these address numbers coincide, the coordinates of the fulcrum found are supported as coordinates

  point of departure or point of arrival in a

  which may be overloaded in the data memory 82 of the navigation system. At step 111 a

  new introduction is then requested. If the numbers

  ros address do not coincide, we search in step 112 other address numbers. In the case where no other fulcrum address number is

  most found in the data set, this is indi-

  in step 113 on diode 85 and in step 114

  the introduction is stopped. It can be repeated se-

  Figure 19. If, however, other numbers of

  are found, the next higher address number is called in step 115 and compared to step 116 with the entered address number. If it is still not superior to the entered address number,

  the program, through a loop 117 re-

  comes to step 109 and checks whether there is now coincidence or if there are still other numbers

  address in the data set.

  This process is repeated until the called address number in step 115 coincides with or is greater than the entered address number. In the latter case, the point of departure or arrival introduced is between the two points of support of the last-called track. At step 118 the coordinates of the starting point or the point

  of arrival, must now be determined by

  corresponding to the difference of their number of

  draws by linear interpolation between the coordinates

  born from the two points of support called and memorized intermediately last. Coordinates

  thus determined are at step 119 assigned to the

  address point of departure or arrival point and are supported in the portion that may be overloaded with the data memory 82 of the navigation system. With step 120, the return to

  functional diagram according to figure 19.

  This subroutine is covered by the same

  way, whether for the introduction of the point of departure

  also for the introduction of one or more

  if they arrive. It is then of little importance

  rather than as a starting point or point of

  an address number is entered on a

or on a place.

  After the arrival of the starting point and the arrival point, the navigation system determines, by means of coordinates, taken from the data memory or determined by interpolation, from the point of departure and arrival introduced, a vector of

  purpose by subtracting the coordinates from the point of de-

  part and point of arrival. This goal vector is in-

  in polar coordinates on diode 85, the

  direction 95 indicating the direction towards

  arrival point and the display 88 indicating the distance

  between the point of departure and the point of

  riveted. During the navigation trip, the location of the vehicle at a given time is determined using the known esteem navigation and the goal vector is then, in a known manner for a goal search navigation. , determined from the location

  momentary of the vehicle and displayed.

  In the above, the word "diode 85" or

  LCD stands for "LCD Display".

-15

Claims (7)

  1.- Method for determining and memorizing   essential data for a representation of a re-   road bucket in a data memory, which is used in a vehicle, with a navigation on the air, to find a purpose called, characterized in that: a) at each channel (23) of the representation of the network   is assigned a distinctive sign which is de-   stored in the data memory, b) from a collection of data for each channel (23) of the road network representation, are successively called, by an address number associated with them, and as hardware of mark points (24) on or against the track (23), the coordinates of these points   (24), such as centers of gravity of   connections, distribution connections and the like,   and this data material of the way (23) is memo- rised intermediately,   (c) the data of the points of support (24) assigned to the   the smallest and largest address hero are   first called and memorized intermedia-   as an initial point and a terminal point, and a line is drawn between this initial point and this end point, d) the coordinates of the other points of support (24) of   the path are successively called pro   and their distance from the right is determined   e) the largest distance respectively determined is compared with a predefined limit value (a), f) in the case where the greatest support distance is less than the limit value (a), only the data points of support (24) assigned number   of the largest and smallest address are memo-   rised, with the distinctive sign of the track, as essential data, all the others   the points of support of the track being, on the other hand,   awarded, (g) where the greater distance from the fulcrum is greater than the limit value (a), that point   support is memorized intermediately in sup-   plement as a new endpoint, a new line being drawn between it and the fulcrum (24) assigned the smallest address number and playing the role of initial point, and another line drawn between the new point terminal   and the fulcrum (24) assigned to the address number   highest and playing the role of the previous endpoint,   h) steps d), e), f) and g) of the process are repeated   for each new straight line until all distances between the initial point and the   end point of each of the lines are less than   above the predefined limit value (a),   i) only are stored as essential data.   tial data, the data of the fulcrums and the lane sign that were found as initial and terminal points.   2. The process according to claim 1, wherein   characterized in that the distances (a) from the bearing points (24) to the straight lines are determined progressively.   from one end of the track.   3. The process according to claim 2, wherein   characterized in that the distances from the fulcrum points (24) to the lines are progressively memorized intermediate and compared with the distance from the respective previous point of contact until the distance decreases, and the greatest distance from the point   is then compared with the pre-existing limit value defined (a).   4. Process according to any one of   Claims 1 to 3, characterized in that, in the case of track layouts for which more than two support points (24) have been obtained, from three successive points of support, the distance between the point of medial support and a straight line passing through the first and the   third point of support, is determined, and this   tance is compared with a predefined value of one   limit, and in the case where this distance is less than   the value of the limit, the fulcrum is sup-   awarded for the smoothing of the track layout and is not   taken into account in the data memory.   5. A process according to claim 4, characterized   characterized in that for the smoothing of the path of the track, the first three points of support are first called, that progressing then from a fulcrum (24), three other points of support are called for the   smoothing of the track layout, and these steps continue   wind until the last fulcrum of the way be apprehended.   6. A process according to claim 5, characterized   characterized in that, in the case where the distance from the median fulcrum of three successive fulcrums (24) is less than the value of the limit, this point is deleted in the immediately following succession of three points d (24) and is no longer taken into account.   7. Process according to any one of   Claims 1 to 6, characterized in that the differences   The process steps are again processed for each channel in the road network representation.   according to an electronic data processing. 35.