JPS6057066B2 - Automotive course guidance system with memory retention mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an in-vehicle course guidance system with a memory storage mechanism, in particular, an electronic display mounted on the driver's seat of a passenger car, and a map showing roads etc. on the display screen of the display. In a course guidance system that extracts the location of the vehicle using a direction sensor and a speed sensor mounted on the vehicle body, plots it on the display, and guides the driving course by correlating it with the map. In-vehicle course guidance with a memory retention mechanism that makes it possible to retain the contents of the system's memory, which stores travel trajectory information, for a predetermined period of time even when the engine key is removed from the passenger car. It's about systems.

Recently, microcomputers have become relatively easy to obtain, and they are now being considered as driving navigators for automobiles.

Direction sensor and speed sensor as one of this kind of navigator? The driving position of the car is extracted using the above-mentioned software, and the driving trajectory is plotted on, for example, a cathode ray tube display, and a road map is associated with the display, so that the plot extends along the road on the map. Systems are being developed to guide the course.
When adopting this system, in order to retain the contents of the system's memory even if the power is turned off, since the power of in-vehicle electronic devices is generally turned off when the car's engine key is removed, It is necessary to use non-volatile memory or to perform battery backup using low power consumption CMOS memory.

However, if these are used, they will be considerably more expensive than general volatile memories in terms of cost. The driving trajectory information used in this system usually needs to be kept for a relatively short period of time, such as when shopping or eating while driving. Therefore, it is desirable to use an inexpensive general volatile memory so that the contents of the memory can be retained even if the engine key is removed from the vehicle. The present invention solves this problem by using a general volatile memory to supply power to the system for a predetermined time even when the car's engine key is removed, and the contents of the memory are immediately destroyed. The purpose is to ensure that there are no

Further, when the engine key of the car is removed and the power switch of the system is set to OFF, the purpose is to shorten the power supply time and avoid unnecessary consumption of power. This will be explained below with reference to the drawings. FIG. 1 is a perspective view of an entire embodiment of a unitized course guidance system of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is position information stored in the trajectory memory shown in FIG. FIG. 4 is an explanatory diagram for explaining the storage mode and readout mode, and FIG. 4 shows the configuration of an embodiment of the memory holding mechanism according to the present invention, which is not shown in FIG. 2.

In FIG. 1, 1 is a display screen of a cathode ray tube display, 2 is a shade part, 3 is a map printed on, for example, a transparent film, 4 is a map insertion guide groove, 5 is a map fixing means, and 6 is a traveling vehicle. It represents the trajectory.

As will be described later with reference to FIG. 2, a direction sensor and a speed sensor are mounted on the vehicle body to extract the momentary running position from the starting point, for example, and display the running trajectory 6 on the display screen 1 of the cathode ray tube display. Let's plot it.

On the other hand, a map 3 printed on a transparent film is inserted from below in the figure along the map insertion guide groove, and the map is positioned in front of the display screen 1 and fixed by the fixing means 5. be done. Needless to say, consideration has been given to displaying the trajectory 6 in accordance with the scale of the map. Then, the traveling locus 6 is made to appear sequentially along the desired traveling route on the map, and the driver or passenger knows the current traveling position from the correspondence between the traveling locus 6 and the map, The direction, current position, etc. are determined. FIG. 2 shows an overall block diagram of one embodiment of the present invention.

Reference numeral 7 in the figure is a direction sensor that detects the direction in which the vehicle is traveling in accordance with a certain reference direction. 8 is a speed sensor which emits clock pulses corresponding to, for example, the rotation of the wheels.

Reference numeral 9 indicates input keys, and various keys are provided on the front surface of the shade portion and the side surface of the display body as shown in FIG. 1;
represents the display.

Direction information from the direction sensor 7 is converted into a digital signal by an A/D converter 11, and converted into angle information by an angle converter 12.

On the other hand, the clock pulses from the speed sensor 8 are counted by a pulse counter 13, so that a sample clock can be output, for example, every 10 revolutions of the wheel. Every time the sample clock is issued, the angle information from the angle conversion section 12 is supplied to the X component calculation section 15X and the Y component calculation section 15Y via the angle correction section 14. Then, the calculation unit 15X extracts the change on the x-axis based on the direction (north), adds it to the cumulative value of the change on the x-axis up to that point, calculates the current position coordinates on the x-axis, and memorizes the trajectory. The data is supplied to be stored in bank #0 (BANK) of river 6. In addition, the calculation unit 15Y similarly extracts the change on the Y axis, adds it to the cumulative value of the Y axis change up to that point, calculates the current position coordinates on the Y axis, and calculates the current position coordinates on the Y axis (bank #0 of the trajectory memory 16).
BANK). That is, for example, when the coordinates of the starting point are (0, 0), the coordinate values of the current position are calculated and supplied to the trajectory memory 16. The contents of the trajectory memo 1 river 6 are read out for transcribing to the trajectory memory 18, subjected to a predetermined conversion in the memory conversion processing section 17, and stored on the trajectory memory 18.

In this case, a conversion is performed that corresponds to the map scale, but
This will be described later with reference to FIG. The contents of the trajectory memory 18 are read to be transferred to the trajectory display memory 20, and are subjected to a predetermined conversion such as parallel movement in the memory conversion processing section 19, and then stored in the trajectory display memory 20. The contents of the trajectory display memory 20 correspond to the image graphics displayed by the display 10, and are read out via the display drive circuit section 21 and supplied to the display 10. That is, a traveling trajectory 6 as shown in FIG. 1 is obtained. The traveling trajectory 6 is observed through a map drawn on a transparent sheet shown in FIG. 1, and is matched with a desired road on the map to provide course guidance. Reference numeral 22 is a scale register in which scale information of the set map shown in FIG.

The contents of the register 22 are supplied to the memory conversion processing section 17 and used when transcribing the contents of the trajectory memo I month 6 to the trajectory memo I river 8. Further, the contents of the register 22 are notified to the sampling interval determining unit 23 and the memory address generating unit 24
The processing during this time will be described later with reference to FIG. 3. 25 is a θ correction register, and a correction value for correcting the angular deviation between the above-mentioned travel trajectory and the map when actually driving on a road is entered by input key 9.
It is set from

Then, the content of the trajectory memory 16 is calculated using the correction value set in the adjustment mode, that is, the correction value set to correct the angular deviation in the adjustment mode such as when the unit shown in FIG. 1 is mounted on the vehicle body. When transcribing to the trajectory memory 18, the above-mentioned angular deviation is corrected. 26 is X
, Y, O correction register, and when the map is set as shown in FIG.
Correction data is set via the input key 9 in order to correct the slight distortion between the two.

Then, when the contents of the trajectory memory 18 are transferred to the trajectory display memory 20, the above distortion is corrected in the memory conversion processing section 19. Reference numeral 27 is a parallel movement and/or rotation movement register, which is used to move the entire travel trajectory 6 on the display 10 in parallel or rotate it when the map 3 set as shown in FIG. 1 is replaced with a new map. When the movement amount information is set from the input key 9 and the contents of the trajectory memory 18 are transferred to the trajectory display memory 20, the memory conversion processing section 19
The above-mentioned parallel movement and rotation are performed.

28 is a count value memory, which stores the pulse counter 13 at the time when the car passes, for example, a railroad crossing or a bridge.
The content is set and used for plotting the passing position on the display screen of the display 10 in a display mode different from that of the traveling trajectory 6 described above.

That is, a memory mark of a brighter point is left in the travel trajectory 6 and is used for alignment with the map. Reference numeral 29 denotes a comparison processing section, which is used to write marks on the locus display memory 20 corresponding to points corresponding to the contents of the count value memory 28. Furthermore, 30 is an encoder that generates a code corresponding to input information from the input key 9. The display drive circuit 21 shown in FIG. 2 receives suppress mode instruction information from the encoder 30 and running information from the speed sensor 8, and suppresses the display on the display 10 while the vehicle is running. The display suppressor has a display suppressing function to prevent the driver from being undesirably distracted by the display 10 while driving.

Said X component calculation section 15X. ．． The main processes in the Y component calculation section 15Y1 trajectory memo i river 6, memory conversion processing section 17, and trajectory memo i river 8 will be described in detail with reference to FIG. As mentioned above, the X component calculation section 15X and the Y component calculation section 15Y
calculates the coordinates (Xl, yi) of the vehicle traveling position at the time corresponding to each sample clock, for example, using the coordinates (0, 0) of the start point.

This result is stored in the trajectory memory 16, and if this aspect is illustrated corresponding to the traveling trajectory 6, it can be considered as the one shown on the left side of FIG. 3A. That is, from the coordinates (a), 0) of the starting point to (Xn-1, yn-1)9'' (X29
y2)9(Xl9yl)9(XO9yO) is stored in the trajectory memory 16. For example, the trajectory memo I river 6 includes #0 bank (BANK) for 128 words and #1 bank for 64 words.
Equipped with bank or #5 bank. Then, 128 coordinates starting from the illustrated coordinates (XO, yO), that is, (
Xl27, yl2T) are sequentially stored in the #0 bank using, for example, a bush-down method, and the coordinate information overflowing from the #0 bank is extracted, for example, one in two, and stored in the #1 bank using a bush-down method. For example, one out of every two pieces of coordinate information overflowing from the #1 bank is extracted and stored in the #2 bank in a bush-down manner. The same holds true for storage in banks #3 to #5. In other words, as shown in Figure 3B, the current location (XO,
The coordinate information for 128 pieces from yO) is for each sample●
It is stored in bank #0 for each clock, and the current location (
XO, yO) From the 12th to the 256th,
One piece of coordinate information is stored in bank #1 every two sample clocks.

Similarly, from the 51st to the 1024th item, there is one piece of coordinate information for every 4 sample clocks. The data will be stored in the individual #2 bank. Furthermore, bank #3 has one clock for every 8 sample clocks, bank #4 has one clock for every 16 sample clocks, and bank #5 has one clock for 32 sample clocks.
One by one is stored in each clock. When using a map as described above, the travel trajectory on the display 10 should be displayed in a manner that matches the scale of the map.

For this reason, when displaying the travel trajectory 6 corresponding to the map with the smallest scale, the coordinate information on the #0 bank is sampled at the interval RL (without sampling) as shown in FIG. 3C. The data are read out sequentially to generate a travel trajectory consisting of 128 points. In addition, when using a map with a scale factor of approximately twice, sampling intervals R2.0 from bank #0. J (extract every other item) to read out the coordinate information for the difficult pieces, and read out the coordinate information for 64 pieces from the #1 bank at the sampling interval r1,
A travel trajectory consisting of a total of 128 points is generated. Similarly, when using a map with a scale of approximately 32 times, every 32 points from bank #0, every 1G from bank #1, every 8 points from bank #2, and every 8 points from bank #3. Every four points, every two points from the #4 bank, and all the points are read from the #5 bank to generate a travel trajectory consisting of a total of 128 points.
When transcribing the contents of the trajectory memory 16 to the trajectory memory 8, scale information is set in the scale register 22 in accordance with the above-mentioned scale rate, and the above-mentioned sampling interval is determined accordingly. A corresponding memory address is generated. Then, based on the address, the trajectory memory 1
6 is accessed. During this time, the above-mentioned 0 correction register 25
Correction is performed based on the contents of , but a detailed explanation thereof will be omitted in connection with FIG. 2. However, in extracting 128 points from the contents of the trajectory memory 16 and storing them in the trajectory memory 18, the memory conversion processing unit 17 converts the current coordinate The position is the origin (0, 0), the previous coordinate position is (X1-XO, yl-YO), and the previous coordinate position is (
X2-XO, y2-YO), . . . are converted and transferred to the locus memory 18. By doing so, when displaying on the display 10, it becomes possible to process the current position as a reference, and it becomes easy to make various adjustments. An in-vehicle course guidance system according to an embodiment of the present invention has the configuration and functions as described above, but the memory of the system, such as the trajectory memory 16, is replaced by a general volatile memory. In this case, even if the engine key of the automobile is removed, the contents of the memory need to be retained without being destroyed for a relatively short period of time, such as when shopping or eating while driving.

The configuration of one embodiment of the memory holding mechanism according to the present invention will be described in detail below with reference to FIG. In Figure 4, 31 is a battery, 32 is a relay, 33 is a DC/DC converter, 34
is a system CPU/memory unit including the trajectory memory 16, etc.;
35 is the main power switch, which connects and disconnects the power to the entire system such as the display device and sensors, and is normally set to the ON state at all times and is inoperable by general users; 36 is the main power switch. A relay drive circuit that operates the relay 32, 37 is a timer counter, 38
39 is a decoder that determines the set time for the timer counter 37; 39 is a timer select switch for externally instructing the set time for the timer counter 37; 40;
41 is an AND circuit, 42 and 43 are inverter circuits, 44 is an OR circuit, 45 is an ignition signal input terminal, 46 is an ignition detection circuit, 47 is a charge signal input terminal, 48 is a charge detection circuit, 49 is a system display section only 50 represents a system display unit including a display 10. The power switch 50 has no relation to sensors or the like.

In Figure 4, during normal use, the main power switch 3
5 and a power switch 49 for turning ON/OFF the display on the system display section 50 are both in the ON state.

Further, the ignition signal and the charge signal, which are signals from the vehicle, appearing on the ignition signal input terminal 45 and the charge signal input terminal 47 are also in the ON state. In this state, HIGH is output from the ignition detection circuit 46 and the charge detection circuit 48, the output of the OR circuit 44 is HIGHl, the output of the AND circuit 40 is HIGH, and the relay drive circuit 36 is set to 0N. , relay 32 becomes ON. Therefore, D
Power is supplied from the battery 31 to the system CPU/memory unit 34 via the C/DC converter 33 . The system display unit 50 also shows that the output of the inverter circuit 43 is HIGH.
Therefore, regardless of whether the above-mentioned subless mode is selected or not, when the car stops running, a screen showing the driving trajectory etc. is displayed. Since the output of the inverter circuit 42 is LOW, the output of the AND circuit 41 is 10 W, and the timer counter 37 does not operate. In the above state, that is, when the main power switch 35 and the power switch 49 are ON, when the engine key of the car is removed and the ignition signal is turned OFF, the output of the ignition detection circuit 46 becomes 10W, and the output of the AND circuit 40 becomes IOW. However, as the output of the inverter circuit 42 becomes HIGH, the output of the AND circuit 41 becomes GH, and the timer counter 37 operates.

As the timer counter 37 operates, the relay drive circuit 36 also operates and keeps the relay 32 in the ON state, so the system C
Power continues to be supplied to the PU/memory unit 34. That is, the contents of the memory are not immediately destroyed but are retained as they are. The set time to the timer counter 37 is supplied from the decoder 38 depending on the state of a timer select switch 39, which is provided in several types as required. After counting the timer holding time received from the decoder 38, the timer counter 37 outputs a STOP signal to the relay drive circuit 36, and sets the relay 32 to 0.
Make it FF. In other words, the power to the system CPU/memory unit 34 is turned off after a predetermined period of time has elapsed since the engine key of the car was removed. If the power switch 49 is in the 0FF state when the ignition signal is 0FF, the output of the inverter circuit 43 is LOW, so the decoder 38 recognizes that the system is not in use and selects the timer select. The timer counter 37 is set to a time shorter than the timer setting time instructed by the switch 39.

Therefore, unnecessary power consumption can be prevented when the power switch 49 is OFF and the system is not in use. When the timer counter 37 is operating, if the ignition signal and charge signal are set to 0N again within the timer setting time, the output of the AND circuit 40 becomes HIGH, and the relay drive circuit 36 unconditionally sets the relay 32 to 0N.
N, power is supplied to the system CPU/memory unit 34, and the system enters a normal operating state.

As explained above, according to the present invention, even if the car's engine key is removed, power can be supplied to the memory of the system for a predetermined period of time, and even if general volatile memory is used, the memory contents can be left unchanged. It becomes possible to hold it.

Further, unnecessary power consumption can be suppressed when the power supply of the system is OFF.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an entire embodiment of a unitized course guidance system of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is position information stored in the trajectory memory shown in FIG. Explanatory diagram illustrating storage mode and readout mode, fourth
The figure shows the configuration of an embodiment of the memory holding mechanism according to the present invention. In the figure, 1 is the display screen of the display, 2 is the shade part,
3 is a map, 4 is a map insertion guide groove, 5 is a map fixing means,
6 is a running track, 7 is a direction sensor, 8 is a speed sensor, 9 is an input key, 10 is a display, 13 is a pulse sensor.
Counter, 16 and 18 are trajectory memories, 17 and 19 are memory conversion processing units, 20 is a trajectory display memory, 21 is a display drive circuit unit, 22 is a scale register, 23 is a sampling interval determination unit, and 24 is a memory address generation unit , 26 is X, Y,
O correction register, 32 is a relay, 34 is a system CPU
36 is a relay drive circuit, 37 is a timer counter, and 49 is a power switch.

Claims (1)

[Claims] 1 A direction sensor and a speed sensor are mounted on the vehicle body, and a display mounted on the vehicle body and a map displayed in correspondence with the display screen of the display are provided, and the direction sensor and the speed sensor In the on-vehicle course guidance system configured to extract the location of the vehicle body, plot the location on the display, and correlate the location with the map, the predetermined travel distance obtained from the speed sensor is and the running direction obtained from the direction sensor.
a trajectory memory that sequentially stores component values and Y component values; a trajectory display memory that stores information extracted by making the contents of the trajectory memory correspond to the scale of the map in correspondence with the display screen of the display; A display is provided for plotting the travel trajectory of the vehicle body on a display screen based on the contents of the trajectory display memory, and a memory retention mechanism is provided for supplying power to the memory of the system including the trajectory memory, the memory retention mechanism being , at least a timer counter that operates for a predetermined time when an ignition signal is not detected, a relay drive circuit that operates based on the output of the timer counter, and a battery and the memory of the system that are connected by the operation of the relay drive circuit. The system is equipped with a relay to retain the contents of the memory of the system for a predetermined period of time when the ignition signal is not detected, and to vary the retention time of the memory contents depending on whether the power switch is turned on or off. An in-vehicle course guidance system featuring a memory retention mechanism.