FI104445B - Landmarks for a vehicle's navigation device and device and method for navigation of a vehicle - Google Patents

Description

104445

Landmark for vehicle navigation equipment and vehicle navigation equipment and method

The invention relates to a land mark for vehicle navigation equipment according to the preamble of claim 1.

The invention also relates to a vehicle navigation apparatus and a navigation method.

10 Navigation equipment known to locate a vehicle using terrain landmarks is known. Current methods have a number of problems: accurately positioned landmarks need to be located at very frequent intervals for accurate and reliable positioning. While navigating on uneven and / or sloping surfaces, despite the abundance of landmarks, it is not obvious that the vehicle will find a sufficient number of landmarks. Known solutions provide relatively reliable information about the horizontal direction, that is, the position of the vehicle in two-dimensional coordination. Obtaining vertical information (= device height information) with sufficient accuracy and speed has been impossible for current devices.

20 .. !! The object of the present invention is to eliminate the deficiencies of the technology described above and to provide a completely new type of navigation equipment and ground control.

: * 'character for the navigation system. I

• * _ 9 • · ·

The invention is based on the fact that the reflective part of a landmark is at least two parts

♦ · · _ such that the width of the reflector portions changes as a function of height in a manner known to the measuring apparatus, and the optical measuring apparatus comprises precise directions 1 • · · __ «* !! '. sensing means for adjusting and detecting the vertical position of the laser beam.

: m '\ 30 More specifically, the landmark of the invention has

characterize what is set forth in the characterizing part of claim 1. L

»· · • · ΓΓ •» »_ • * 104445 2

The navigation apparatus according to the invention, in turn, is characterized by what is stated in the characterizing part of claim 5.

The invention provides considerable advantages.

5

Vehicle vertical information is obtained quickly and reliably. Landmarks are a powerful source of information, despite their simple structure.

Accurate mirror vertical measuring equipment can compensate for obsolete mechanics of the measuring device. Without this feature, it is impossible to achieve high accuracy in vertical measurement.

The combination of a new landmark and accurate out-of-beam radar measuring instrument and method provides an accurate real-time navigation system for the most demanding applications.

The invention will now be further explored by way of exemplifying embodiments of the accompanying drawings.

Fig. 1a is a top plan view of the arrangement of a device according to the invention in a road working machine.

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Fig. 1b is a side elevational view of the arrangement of a device according to the invention in a particular machine.

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Figure 2 schematically shows a navigation device according to the invention.

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Figure 3 is a fragmentary side elevational view of another navigation device according to the invention.

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Fig. 4 is a block diagram of a navigation and computing unit for the navigation apparatus according to the invention.

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Figure 5 is a block diagram of a mirror position adjuster according to the invention.

Figure 6 is a block diagram of a light transmitter according to the invention.

Fig. 7 is a block diagram showing one light receiver according to the invention.

Fig. 8 shows a wiring diagram of one of the voice coil control electronics according to the invention.

Figure 9 is a front view of one landmark according to the invention.

Figure 10 is a block diagram of a horizontal angle calculator according to the invention.

1a, 1b, and 2, the position and position of the vehicle 13 are provided by reflective landmarks 5 measured at the edges of the working area, in accordance with specifications to be determined at a later date. The device 14 measures the horizontal and vertical angles at which the laser beam transmitted from the device 14 is reflected back to the measuring device from the landmark 5.

The device 14 is positioned in the vehicle 13 in such a way that it has an unobstructed view of the road edges.

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In the case of the grader 13, the location may be the boom of the machine as shown in Figures 1a and 1b. The planer cab and gauge frame make up • · · = ···· 25 areas to the rear. However, it is irrelevant to the operation of the device. • · · _________ "* · ''.

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As shown in Figure 2, the device 10 has a laser light source 1 which emits light at a constant wavelength in the vicinity of the device. The laser diode 1 is mounted vertically, ♦ · · ~; 30 that the light hits the center of the rotating mirror 3 in the direction of the axis of rotation.

The light passing through the mirror 3 propagates almost horizontally into the environment and: V returns only if it is reflected from the surface of landmark 5 Γ 104445 4. The returning light no longer forms a narrow beam but is scattered from the landmark 5 in its reflection into a narrow beam. In order to collect as much of the incident light as possible on the LED 7 to detect the landmark 5, the mirror 3 and the lens 2 focusing on the LED 7 must be sufficiently large. At the end of each rotation of the mirror 3, a pulse is generated from the optical reading fork, which after receiving the control electronics e.g. calculates the horizontal and vertical angles at which landmarks 5 were visible and concludes from which marks the measurement was obtained.

10 In order for the beam exiting the measuring device 10 to hit the ground marks 5 at different heights or to allow the road tool 13 to travel along a sloping surface, the vertical angle of the beam must be adjustable by tilting the rotating mirror 3. In the implemented prototype of the measuring device, the vertical deflection of the beam is a completely independent operation of rotation of the mirror 3, whereby the beam can be arbitrarily varied within the limits set by the speed of the actuator and the length of movement. For example, one may try to drive the vertical deflection of the mirror so that the desired landmarks are pointed as often as possible without wasting time.

20 In order to determine unequivocally the position and the position of the vehicle 13, the device 10 must obtain a simultaneous measurement (horizontal and vertical) of three: landmarks 5, whereby one of the solutions can be removed as impossible.

• · · • · * Using data from four landmarks 5 provides a unique solution.

Since one measurement cycle lasts 10 ms, a maximum of one mirror 3 • · · · ;;; Landmark observations made over 25 laps are considered simultaneous (the vehicle moves a few centimeters within 10 ms). In practice, however, it may be common for a beam to not hit four • · · 'V.' during one measurement cycle. ' landmark, but measuring four characters can take longer. In this case, the problem is that the measurements are made at different locations and the vehicle is in a different position. There are a few options available to calculate the position and • position of the vise.

• · »* · a» • ·. a il 104445 5

Assuming that the longitudinal inclination and direction of travel of vehicle 13 do not! change during measurement and with a separate sensor measuring the transverse inclination of the vehicle 13 and the distance traveled, the angular observations obtained from four different landmarks 5 can be converted to a single point measurement. Then the position and asen-5 to can be calculated normally. Another option is to make a model that represents the machine's movement space as accurately as possible. This business model is updated based on direction of travel and distance traveled. A measurement of the transverse tilt of the vehicle 13 can also be combined with the model. Each measurement from landmark 5 is associated with the model using, for example, a Kalman filter.

10

The structure of the measuring device 14 is in simplified form as shown in Figure 3. The measuring device 14 consists of the actual probe 10 and a separate control and counting unit 15. These can be mounted on separate device housings or on the same housing, if necessary.

15

The beam directed at the terrain is produced, for example, by a semiconductor laser 1 attached to the center of a lens 4 cm in diameter. The beam is swept horizontally by means of a rotating mirror 3. The mirror 3 is rotated using a DC motor 19 with a hollow axis. At the end of each rotation, a pulse 11 is obtained from the optical reading fork 20, which is used to determine the horizontal angles corresponding to landmarks 5.

The vertical angle of the mirror 3 is adjusted by the voice coil 17. The position feedback is adjusted by the linear encoder (LVDT) 21 for the adjustment of the voice coil 17. The linear motion of the voice coil 21 is converted to the rotation of the mirror relative to its mounting axis. using a rod 23 mounted through a rotary motor 19 and pivoted on mirror 3. "

To achieve the required measurement accuracy, all joints should be ~

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• _ very small play. The rotating mirror 3 must be light so that the gyratory forces caused by the rotating motion "I I -" do not slow down the adjustment of the vertical angle of the mirror. Instead of mirror 3, the f prism can also be used in the solution of the invention. .

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The beam reflected from the landmark 5 is collected by means of a rotating mirror 3 into a perforated lens 2 which focuses the incident light on the LED 7.

For position measurement, the vertical angle of the beam can be measured once with each rotation of the mirror 3 by means of a second laser 24 and a line camera 25. Laser 24 applies a beam to the mirror, which always reflects back to the row camera 25 according to the position of the mirror 3. Based on the location of the return beam detected by the row camera 25, the angle of the mirror 3 and the outgoing beam can be uniquely determined. The angle measurement accuracy of the mirror 3 can be increased by increasing the distance between the mirror 3 and the row camera 25 and / or increasing the resolution of the row camera 25. Instead of laser 24, laser 1 can also be used, whereby a suitable focusing element, such as a lens, is required in front of the row camera 25.

In addition to the actual measuring device 14, electronics are needed to control the functions of the measuring device and to calculate the position and position as shown in Figure 4.

The control and calculation unit consists of seven electronic cards mounted on the PC bus 36. The cards are optic card 27, horizontal card 29, 20 mirror 3 tilt control card 31, vertical angle card 33, probe control card 35, position and position calculator 37 and l / O card 39.

: The main function of the optic card 27 is to reliably provide the start and end edges of the reflective portion of each landmark 5, for example, a TTL pulse * * * 25 (start and stop pulse). In addition, it can modulate the intensity of the transmitted laser beam so that the reflected beam can be distinguished as reliably as possible from ambient light. The modulation frequency used is about 20 • · · * »*. MHz. The receiver uses a light emitting diode 7, which is connected to a pre-amplifier board in a built-in test apparatus. The amplified signal is transmitted to the optic 30 card 27 for further processing. The optic card 27 further amplifies the signal level and the received signal is filtered by a bandpass filter having a center frequency of I f • a modulation frequency. The filtered signal indicates the • • 104445 edge of the 7-character reflective region. To compensate for variations in ambient light, the card uses a feedback loop that corrects the gain of the preamplifier relative to the amount of backlight emitted from the LED 7.

5 The horizontal angle card 29 is coupled to the optic card 27, where it receives start and stop pulses corresponding to each landmark 5. Its main function is to store in the FIFO memory a counter reading of the horizontal rotation angle of the mirror corresponding to each pulse received. In addition, it stores the counter value corresponding to the full rotation of the mirror 3. The card 29 stores the counter counts of all the landmarks 5 detected during one revolution of the mirror 5, when the round is complete, it interrupts the probe 10 control card processor which reads the stored counter counts into its own memory.

With the mirror tilt control card 31, the tilt angle 3 of the rotating mirror 3 is controlled by 15 "voice coils" 17. The object of the design is to achieve a very fast response in controlling the tilt angle of the mirror 3 and a sufficiently large and programmatically adjustable vertical angle range.

The voice coil 17 functions in the same manner as in the loudspeaker. It has a coil wound of copper wire 20 surrounded by a permanent magnet core. The force between the coil and the magnet depends on the amount of current supplied to the coil. Suitable current ··:: Controls the position of the coil inside the magnet. Articulation transmits = «t« s • · · __; ·] To change the tilt angle of the reel movement mirror. The position of the coil is measured • · * · φ _ directly in a linear crash with a resolution of a few micrometers.

· ::: '25] • · *

The mirror position adjuster is fully in accordance with Figure 5. In practice, however

indeed, a simpler structure, at least the current control 47 being omitted, is sufficient. The controller has at least two implementation options. It is possible that a ready-made commercial control and strength = «« · 30 tincture, for example Seidel 02S or Maxon PSC, can be used for positioning the coil 4T. However, the preferred option is to make the adjustment programmatically and use a simple amplifier board of FIG. 8, which is controlled by the analog output of the I / O board 30.

I · · 104445 8

Accurate vertical positioning of the machine 13 requires that the laser beam output angle be known precisely. Continuous measurement of this angle is obtained from the LVDT sensor 21 connected to the voice coil 17. However, the most accurate result is obtained by measuring the beam departure angle directly from the beam 5. This is accomplished using either a separate laser diode 24 or a laser diode 1, whereby the line camera 25 requires a focusing lens, a line sensor 25 (e.g., a CCD sensor) and electronics connected thereto. The function of the vertical angle card 33 is to read the contents of the row sensor 25 once in a rotation of a mirror 3 (for example, a resolution of 2048 pixels) and to find as closely as possible the pixels of the camera 25 to which the laser 24 was exposed. In practice, the laser 24 illuminates a few pixels wide area of the line camera 25, so that the data provided by the camera 25 also shows a lighted area a few pixels wide. Vertical angle card 33 looks for the left and right edges of this region, for example, the weighted average of which is proportional to the vertical angle of the laser beam.

15

The probe control card 35 controls the operation of the rotary motor 19 and the voice coil 17. It also reads from the FIFO of the horizontal angle card 29 the counter values corresponding to the angles of all the landmarks 5 detected during the rotation of the mirror 3 and the reading corresponding to the full rotation. From this data, it calculates 20 horizontal angles with 5 landmarks each. The control card 35 knows the location of all landmarks 5 and the position and measured angles of the vehicle 13, and calculates which character each angle reads. The control card 35 also reads from the «i ·: vertical angle card 33 once in a rotation of the mirror 3, which can * * retrieve the exact vertical angle of the laser beam corresponding to the table. The control card «· · · 1» 25 35 sends the vehicle 13 position and position descending card 37 angular readings, corresponding landmark symbols, distance traveled and vehicle transverse tilt once for each mirror rotation (100 Hz).

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The tasks of the probe control card 35 require quite a lot of computing power. Kor- «k ·

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The t / 30 t must have a connection to PC bus 36, non-volatile memory, and at least one parallel port.

»» 1 »1 • · ·» 104445 9

The Position and Position Calculation Card 37 is required to calculate the position and position of the measurement data from the horizontal and vertical angles where landmarks have been detected. The calculation can be supported by measurement of the distance traveled and the transverse tilt of the vehicle. This information is obtained from the probe control card 35. Calculating position 5 and position is a mathematically difficult operation, and a minimum of 486 class CPU card must be available if you want to access multiple Hertz. In addition to high computing power, the card requires enough non-volatile memory, one parallel port, and one RS232 port. For example, the ASC486SLC fulfills these requirements.

10 I / O cards 39 are required to supply the setpoint for mirror rotation and tilt motors. Two 12-bit D / A converters are required for this. In addition, analog and digital inputs are needed to connect the mirror tilt angle LVDT sensor, the machine's odometer, and the transverse tilt sensors. In addition, the card must be connected to a PC bus. For example, the requirements are met by Ajeco's ANDI-MM.

6, the transmission electronics of the laser 1 consists of an oscillator 70 which controls a power amplifier 72. The power amplifier, in turn, supplies a laser 1, 20, which is fed back to the power amplifier 72.

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»~.:! As shown in Figure 7, the receiver electronics typically consist of a receive * * *: '' output diode 7, the signal of which is amplified in the preamplifier 74. The resulting signal is filtered at low frequencies by a low pass filter 76 and a low pass filter 1 76; 25, the filtered signal is integrated in integrator 78, the output of which is used as feedback to the light-emitting diode 7. In the second branch, the center frequency f0 is separated from the signal by bandpass filter 80. The filtered signal is amplified • ~ «·» \ Editor 84 START and STOP pulses.

# ·:,.: ’30

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T Adjusting the vertical angle of the mirror 3 is done, for example, by software on the probe control computer. In this solution, the computer calculates the angle at which the mirror should be driven, measures the current angle of the mirror, and calculates a control value for the amplifier circuit controlling the voice coil 17. The connection is according to Fig. 8. The amplifier is designed to operate at a single-sided voltage (OV and + 24V). The control voltage level from I / O cor 39 should be increased by about 12 V in order to operate at control voltage values around the zero voltage. The voltage is raised by a zener diode 64 supplied by a constant current source. The voice coil 17 is powered by two power operation amplifiers 66 which are connected to the bridge. This connection enables the entire supply voltage range to be utilized to control the coil 17. In order to ensure stability of the connection, the supply voltages of the operational amplifiers 10 to 66 must be buffered by capacitors 68. In addition, the output voltages of the amplifiers must be filtered as shown.

9, the landmarks 5 used to locate the road working machine 13 are required e.g. reasonable size and price, weatherproof and • 15 easy to install. In addition, the sign 5 should be such that it can be detected at a sufficiently wide viewing angle and at sufficiently large distances. Another important requirement is that the mark should provide information about the height of the laser beam that was swept over the mark.

For example, the landmark J 5 of Figure 9 fulfills the above requirements. Its triangular reflector portions 12 are, for example, 3M made of Gradient reflector material. Such reflective material reflects · «·! · · · '** Incoming beam back to beam direction. This property is called retroreflectivity. The reflectors 12 are self-adhesive and can be attached to, for example, weatherproof plywood. Between the triangular reflector portions 12 f * o, a non-reflective non-reflective spacer 94 is formed, which defines the center of the sign 5 at the return beam and the height of the sweep «*«! * At the sign 5. The marks 5 can be mounted at arbitrary positions: / li, along the road, as long as they are detectable by the sensor and mounted in a known position 30, preferably such that the non-reflective spacing 94 is in a vertical position. Later, a method by which the beam hit height can be • described. · • »»: calculates the middle of the character.

«* • * · 9 r« 9 · 104445 11

The laser beam's hit height to the mark 5 can be solved by utilizing the shape of the mark. When the beam hits the mark, the optic card gives 27 pulses at the beginning and end of both reflective portions. In this way, it is possible to measure the time it takes for the beam to travel over part 12 of each character 5 and between them 94.

However, from this information it is not possible to determine the actual lengths S1, S2 and S3 shown in Fig. 9, since the distance and direction to the sign are unknown. The measurement therefore gives only the segment length ratios S1 / S2 and S3 / S2, denoted here as t1 and t3. When the angle of the beam with respect to the horizontal plane is denoted by p, we can say: 10 sin (P) = (h1-h2) / S1 = (h3-h2) / S2 = (h4-h3) / S3 (1) t1 = S1 / S2 = (M-h2) / (h2-h3) (2) 15 t3 = S3 / S2 = (h3-h4) / (h2-h3) (3) denote k = -1 / by today's (4) SI = V ( h1-h2) 2+ (a + kxhl) 2 i5) (i: S2 = y / c2 + {h2-h3) 2 (6)

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· <I I »· t · *» 2: ♦ ·! S3 {h3-h4) 2 + a + kxh4) 2 (7) v • I · f ψ »a ·» · fj '20 The value h sought is the mean of the heights h2 and h3: «ft * h = (h2 + h3) / 2 (8) * * I * • · ·

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From equations (1-7), the following expressions can be derived for h2 and h3: t · '' / 25 f. * a1 * h22 + (b1 + c1 * h3) * h2 + d1 * h32 + e1 * h3 + f1 = 0 (9) k i * I. II * 104445 12 a2 * h3z + (b2 + c2 * h2) * h3 + d2 * h22 + e2 * h2 + f2 = 0 (10) where 5 a1 = k2 + 2 * k2 * t1 + k2 * t12 (11) b1 = 2 * a * k * t1 + 2 * a * k (12) c1 = -2 * k2 * t1 * (t1 + 1) (13) 10 d1 = k2 * t12 (14) e1 = -2 * a * k * t1 (15) 15 f1 = a2-t12 * c2 (16) a2 = k2 * (1 + 2 * t3 + t32) (17) b2 = 2 * a * k * (1 + t3) (18) 20 c2 = -2 * k2 * t3 * (1 + t3) (19) d2 = k2 * t32 (20) • · · · · · · · · · mw 25 e2 = −2 * t3 * a * k (21 ) • · · l:;:; f2 = az-t32 * c2 (22) • · · • · · •

From equations (9) and (10) it is not possible to solve h2 and h3 in closed form 30. In practice, the best way to solve for h as a function of t1 and t3 is to use tables. For this, a three-dimensional table is needed, from which the measured values of t1 and t3 are used to obtain the best value for h. The result is sufficiently accurate

J

i 104445 13 using a table of n, 3 x 4000 numbers with a maximum error of h of 2.5 mm.

To get a quick look up from the table, sort it by t1 in order of magnitude. Using the measured t1 as the search key, the table closes with the half-search to find the value closest to t1. Around this value, look for the row in the 5 tables that minimizes the error abs (t1-t1, au,) + abs (t3-t3laul). This line contains the best value for h.

To test the computational need of the application procedure, the above algorithm was practically tested with a C language program. According to the measurements made, the search of the value of h in the table typically takes 0.3 ms when running the program on a 50 MHz 486-PC. Based on the test, the algorithm runs fast enough for real-time measurement.

10, the horizontal angle calculation card 29 is connected to the PC bus 62 15 so that both writing to and reading from the card are possible. The interface logic details are not provided here.

The pulse generator 51 outputs a logical 1 level with a 5 in the field of view of the receiver diode 7 and otherwise a logical 0 level. In the design of the operation 20, by means of a D-flipper providing the leading edge of the sign, the "stop" signal and the corresponding end edge (= inversion of the light-emitting diode 7 signal) respectively are thought to be "stop" sig-

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1 «« - 'nal. The use of flip flops is designed to protect against rapid interference signals at the edges of the characters as the flip flops are only reset to a suitable level

Ml after the delay.

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The rotational speed of a rotating mirror is measured by means of an optical reading fork located on its axis. For example, the numerical fork 11 shown in more detail in Fig. 3 gives: 360 ° a short pulse per revolution for block 52. '

To generate a rotation pulse, the LED of the reading fork 11 is • powered by a resistor connected to a constant voltage. Fork LED Diode Gives Directly · · ·

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: · 'TTL level pulse. On the other hand, the mirror rotation speed is adjusted. Γ • Il • «104445 14

The "start", "stop" and "360" signals from the landmark 5 resulting from the rotation of the mirror 3 cause the controller logic block 53 to include the contents of the angular steps and to write the "start", "stop" and "360" signals to the FIFO memory 55.

The "360" signal resets the contents of the counters 54 after writing to FIFO 55.

When writing to FIFO 55, the controller logic 53 must take care that the write never reaches the active edge of the counters 54 of the clock signals, but only when the counter is stable.

From bus 62, the START / STOP logic states of the measurement event can be provided. STOP mode stops the measurement immediately. The START pulse starts 15 measurements after the next "360" pulse.

Counter 54 is formed, for example, from 8-bit circuits which are chained so that they step simultaneously and together form a 24-bit counter. It is thus possible to rotate the mirror very swiftly, ···; 20 again without risk of 54 overflows of counters.

• · • I · ·

Il ·: \ FIFO memory has 55 depths of 64 memory slots. FIFO memories 55 must be capable of being cleared from bus 62 by hand. So is their "EF" (= empty flag) and

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The "FF" (= full flag) flags must be read in pairs (upper / lower 16 bits) on 25 buses 62. The FIFO 55 stores the count of the counter 54 each time a "start", "stop" or "360" is received on the card. "-pulse. In addition to the counter reading, information is stored about what the event reads ("start", "stop" or "360" signal).

«FIFO still has 5 free bits, at least some of which can be taken \ .I. for use, eg for detecting overflow in the counter chain.

* "30 • · · • ♦ · · '. The bus buffers 56 connect the card to the PC bus 62. In the reading event, the FIFO' '' 55 output counter must be incremented each time the buffer is read.

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Address encoding 57 provides the card with a base address to be selected on bus 62, for example by short circuits. As usual, the various registers on the card "appear" around the base address at the addresses encoded by the lowest address bits.

5 The different positions of the corner card must be able to be set and read by means of the write and read pen discipline 58.

At least the following operations must be available from the write buffer of block 58: - Simultaneous reset of FIFO memories 55 - Reset of corner card 10

And the following variables must be readable from the read buffer of block 58: -Fl-FO states can be read in pairs by their "EF" and "FF" flags, -possible cause of interruption.

It is advantageous for the invention that any of the FIFO 55 status signals could be wired to cause interruption on the bus (e.g., by means of a logical OR). The reason for the interruption could be read from the read buffer. This would better prepare for abnormal situations.

; ; Although the triangular shape of the reflectors 12 of the landmark 5 is advantageous because of its easy mathematical control, it is not the only alternative to the solution according to the invention. The triangles 12 may be • = to obtain information about the landmark is that the width of the at least one reflector pattern 12 II · ^ 25 or the gap 94 changes unequivocally in the height direction of the landmark 5 and [this dependency is known to the receiving device 14. A unique change in width The width of the landmark element 12 or 94 is not: ·! ·. the same at two different elevation positions of landmark 5. The width dependency of the landmark 5 can be, for example, linear, 30 exponential or logarithmic.

A part 5 is sufficient if the vehicle 13 is moving in a known plane. If more accurate! no location information for vehicle 13 is available, landmark 104445 16 requires two uniquely variable parts 12 or 94.

The following features are typical of Landmark 5: 5 1. Landmarks 5 are made of a 3M traffic sign film.

2. The marks 5 are shaped so as to calculate both the height of the beam on the surface of the mark and the inclination of the machine in relation to the mark.

3. The size of the character 5 is approximately 120 * 60 or 60 * 60 cm. (The appropriate size is determined experimentally.) 4. The marks 5 are placed along the road edges so that the measuring distance and the vertical deflection range of the beam 15 are sufficient.

A preferred embodiment of the invention is designed to operate, for example, in the following operating environment:; 1. Machine tool 13 may be inclined ± 3 ° to the horizontal.

\ 2. The machine 13 has a forward speed of up to 7 km / h and a 9 · backward speed of 15 km / h. When reversing, it is not necessary to lower the position or height of the machine '' 'II except that the machine will not lose its location information in a known environment.

3. The system is splash-proof.

• * * • • · · · 4. The unit operates in all lighting conditions except for a maximum of 30 pours of rain or heavy fog.

5. The apparatus operates within a specified accuracy with a gradient vibration acceleration of less than 0.1 g and an amplitude of less than 5 mm.

The following are typical performance objectives of the invention.

5 1. The rotation speed of the laser beam is adjustable and the maximum min speed is 100 r / s.

2. The vertical deviation of the laser beam from the horizontal is ± 7 ° and the deflection rate is 50 ° / s. The deflection rate is adjustable, (i.e., edge to edge 280 ms). The angle of the mirror is measured with a semiconductor laser and a line sensor.

3. The accuracy of the horizontal alignment mark shall be at least 0,1 °. (i.e., 35 mm at 20 m) 15 4. The accuracy of the vertical alignment mark shall be at least 0,01 °. (i.e. 3.5 mm at 20 m) 5. Measuring distance 3 - 200 m.

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i i i:;: γ 6. Vertical deflection range of laser beam ± 7 °.

·. 7. The positioning accuracy of the device in the x and y directions is ± 10 cm '·' · and in the z direction ± 2 cm.

i:: J 7 • · · • · · · * · - • · · -z 9 9 9 9 9 9 9 - f I <1

Claims (9)

1. Landmark (5) reflecting eating at least in the direction of an incoming light beam and intended to be used as a landmark (5) for a navigation system (14) for a vehicle (13), in which system a predetermined ginger repetition angle is searched by means of a light source (1) for determining the position of the vehicle (13) in a three-dimensional coordinate system, characterized in that - each landmark (5) is formed by at least two separate reflector portions (12) and by a non-reflective region (94) located therebetween, - the width of the at least part (12, 94) of the landmark (5) varies unequivocally in the height of the landmark (5). Landmark (5) according to claim 1, characterized in that the reflector portions (12) are rectangular triangles, between which an even, non-reflective area (94) is formed. Landmark (5) according to claim 1, characterized in that the reflector portions (12) are made of parallel triangles and the non-reflecting region (94) has the shape of a truncated triangle. • · • ~ • · · __ • __ • • o Landmark (5) according to claim 1, characterized in that the reflector parts (12) consist of retroreflective material. • · · “· • · · · · · __ • · ·. ·, · 1 ί A navigation device (14) for a vehicle (13), comprising L i - 'i - »« if II - a light source (1), • <i * - • M ^ t · f _ i «· - I« - «« 1 22 104445 - a reflector (3) for reflecting the light from the light source (1) to an object (5), - a horizontal deflector (19) for deflecting the reflector (3) in the horizontal direction and thus for sweeping the light in a a desired angle of space, - a vertical deflector (17) for deflecting the reflector (3) in the vertical direction, and - a receiver (7) for receiving the light reflected back from the object (5), characterized by - the light source (1) and the receiver means (7) are arranged on the same optical axis in such a way that the light source (1) is in the center of an aligning lens (2), and the device (14) is provided with positioning means (24, 25) for determining the position of the reflector (3). Device (14) according to claim 5, characterized in that the positioning device consists of a light source (24) and a row camera (25). Device (14) according to claim 5, characterized in that the same light source as • | · Constitutes the light source for the beam intended to be directed to the landmark (5) acts as • # · *: T: light source (1) for the positioning devices. • · · V Device (14) according to claim 5, characterized in that the vertical deflector • · ·: (17) is a voice coil. «*» • ♦ · Method for determining the position of a vehicle (13) by means of the terrain. * * ·. arranged landmarks (5), whereby • an ambient scanning beam of light is directed from the vehicle (13) towards the landmarks (5), - the reflected light beams from the landmarks (5) received and detected, the characteristic wattage - the height position of the vehicle (13) is calculated from the length of at least two pulses reflected from at least three landmarks (5) and from the angle of the emitting beam. • · • ~ • · • · · · t · »• · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · • 1 • 1 · “· •«