DE3248192A1 - Device for recording data of a motor vehicle before an accident - Google Patents

Abstract

A device is proposed which serves to record data of a motor vehicle before an accident, or for monitoring purposes. In this way, for example the speed data, and data relating to actuation of the brakes, horn, indicator lights, lights etc., are converted into digital signals and fed to a microcomputer with a microprocessor or even only to a shift register in a simplified form. A control and timing unit supplies a clock frequency from a frequency signal of the speed, which clock frequency is stored in a shift register. The data can be fed when required to a printer via a serial output.

Description

The invention relates to a device for registration or recording of data from a motor vehicle, such as speed, brake actuation, horn, light, Flasher or the like before an accident (accident recorder) or for control purposes.

Tachograph to record the speed in a given Time units are known in various designs. In the DOS 28 33 858 is z. B. describes a tachograph that shows the speed of a rotating Records roller or disk. A similar process has been around for a long time used in conventional trucks. The rotation of the disc or roller happens proportionally to the time, the deflection of the recorder is proportional to the speed.

From the DOS 26 19 070 there is still a short-term tempo recorder known for motor vehicles, in which e.g.

with a tape recorder with an endless loop of tape a certain one Period of time before an accident is recorded.

In particular, the speed of the motor vehicle should be used here registered in an accident.

Such devices are mechanically very complex and require accordingly a lot of space .. Furthermore, the accuracy and thus the reliability of the recorded data left something to be desired.

Lately, more and more motor vehicle cells are coming into the traffic that Equipped with an automatic blocking preventer (ABV or ABS system) are. Such devices prevent the wheels from locking, which at the scene of the accident no skid marks are left behind. These skid marks, however, were previously a important evidence to reconstruct the course of the accident. It was because of that Lately the demand has been made that at least such vehicles, if possible, however, every motor vehicle with a so-called "incident recorder" should be equipped to record the data before an accident. In a publication of the VDI (Journal No. 24, 06/11/1982) it was therefore suggested that z. B. Data of the last 200 meters traveled are displayed legibly and all before these "traffic sins" committed 200 meters are automatically deleted.

The main task of the recorder must be speed, brake actuation, Reliably monitor indicators, horns and lights before the accident.

The invention is based on the object of iron such required To create accident recorder, de- in particular the data of the motor vehicle recorded and registered in an accident.

This task is carried out on the basis of a device of the introductory part characterizing type according to the invention thereby Lö.tt that the to be recorded Data intermittently according to a given distance (s) and / or time unit (t) recorded, digitized if necessary and a microcontroller and / or Microprocessor and / or shift register or other electronic memory supplied and that the values stored in each case if necessary - like after an accident - are readable.

The device according to the invention with the characterizing features of the main claim has the advantage that the task set by the experts to create an accident driver solved with little technical effort can be used, with electronics being used which are particularly space-saving is constructed and works with the highest precision1: O As part of the collection of the Electronics in the motor vehicle can use the device according to the invention without great effort to get integrated.

The invention is based on the principle that after a covered Distance from z. B. one meter (equidistant distance intervals), the most important data of the motor vehicle are recorded and stored in digital form. This storage however, only takes place over a certain distance (e.g.

approx. 500 meters), then the saved data is deleted again and replaced by new ones. After an accident, z. B. only the data of the last approx. 500 meters.

The advantageous embodiment according to dependent claim 2 is in conventional technique, d. H. run without a microcomputer or microprocessor. This is advantageous for small series and individual applications. Basically be the recorded data in a RAM memory according to the principle of a shift register or saved after the FILO (FirstInLastOut). The saved Data is read out using a serial interface at the output of the accident recorder will.

According to the embodiment of the invention according to dependent claim 3 is achieved that a speed that can be registered by an 8-bit, as well as another 8 different ones Signals about the state of the motor vehicle are detected simultaneously and by means of parallel inputs are fed to the shift register. '4 after a distance of z. B. another Meter, the speed and the other data are recorded again and transferred to the Shift register entered. The previous 1 data then moves one position further. If the shift register is full, e.g. B.

after 512 registration steps (512 meters), the first one is entered Data record from the shift register he: ejected and thus deleted. Will be an issue the data for the last distance traveled is desired, then by means of a external clock the shift register via an <iter downstream shift register read out serially.

According to the advantageous embodiment of the invention according to the dependent claim 4, the designated analog-frequency converter converts an analog or digital one The output signal from the speedometer is converted into a digital frequency signal.

So that the tachometer signal processed in this way is fed to an 8-bit counter can be, it must be brought to a smaller value by a divider. The downstream control and timing unit can be based on the speed signal after a certain distance (e.g. one meter) a clock signal for registration convey the data to be recorded in the respective stages.

According to the alternative according to dependent claim 5, one of the speed proportional frequency signal generated by means of an angle encoder. For the Retrofitting or installing a digital tachograph can do the familiar Separate speedometer cables and install an angle encoder. This can be done by a perforated disc can be realized, the rotation of which is carried out by means of an inductive encoder, Infrared light barrier or the like. Is detected. In contrast, a voltage / frequency converter connected in parallel to a moving coil instrument of the speedometer. With automobiles With a digital speedometer display, the accident recorder can read directly on the speedometer or on connected to the existing digital speed sensor.

According to the advantageous measures according to dependent claim 6 are also the other data mentioned on brake actuation, etc. also z. B. after each Meter travel distance recorded and the correct control voltage using the level converter transformed or converted into digital signals. An 8-bit level converter can be used Acquire and text eight different wide signals. For clocked input In the shift register, this data must still be fed to an R / S flip-flop.

According to the feature of dependent claim 7 is an emergency battery for Accident recorder provided. This measure is to avoid that in an accident or if the batter is too weak, the data in the shift register is deleted. An additional control lamp should ensure that the power supply is in the correct state Show.

According to the further subclaims 8 to 10, the invention is one advantageous development of the concept of the invention to the effect that microcomputers or microprocessor with associated peripherals can be used. With automobiles with an existing microcomputer for z. B. engine control, ABS braking system and / or Digital dashboards could ai these the tasks for the digital accident Schreiber überehi However, a completely self-sufficient digital accident recorder is advantageous with its own microcomputer. The entire electron can shed and would therefore be subject to unauthorized interference by unauthorized persons withdrawn. Furthermore, the accident recorder can be designed as a plug-in module, what enables the police to seize the clerk at the scene of the accident.

An advantageous and expedient embodiment of the invention is shown in the drawing and explained in more detail in the following description. 1 shows a schematic representation of the components required for detection and registration of the motor vehicle data, FIG. 2 the representation of the voltage supply with control device, Fig. 3 shows a further embodiment of the invention, especially with the use of microcomputers.

The circuit shown in Fig. 1 relates to the registration a signal from the tachometer 10, as well as signals from the braking device 11, the automatic Blocking preventer 12 (ABV, ABS system), the horn 13, the left indicator 14 and right turn signal 15, the lighting device consisting of Standlich 16, low beam 17, and the high beam 18.

Of course, further data can be added to the system will.

The speedometer signal 10 present in analog or digital form is in an analog / frequency converter 19 into a digital output frequency signal 20 This frequency signal 20 is converted to a divider stage 21 which it divided down so far that the speed registered in each case is in an 8-bit Binary counter 22 can be included. For example, the speed can be from Represent 250 km per hour by an 8-bit binary number.

The divider stage 21 is followed by a control and timing stage 23, the control signals after covering a certain distance, e.g. B. one meter, or also after a certain time unit is available. This control unit 23 clocks z. B. the speed recorded in the 8-I; it counter after a distance from Z. B. one meter further. The signal from the 8-bit counter is then sent over a line 24 is fed to an 8-bit D-latch flip-flop 25. The fault from the control and timing unit 23 of 8-bit counter 22 occurs via line 26 and des 8-bit D-lat flip-flops 25 via the connections 27, 28. B. the Clock input and 28 the reset input of flipfl 25.

The other signals of the motor vehicle 11 to 18 are in different Shape before. In order to adapt this to the electronics of the device according to the invention, a level converter 29 is provided, the various signals - if necessary by means of Optocoupler or the like - converted into digital signals with the correct voltage. In addition to the signal from the braking device 11, there is also a signal from the automatic Blocking preventer 12 provided to the exact timing of the use to determine this system.

This should z. B. can be determined at what time and at which location the blocking preventer was active.

The digital signal processed in the 8-bit level converter is transmitted via a Line 30 is fed to an 8-bit R / S flip-flop 31.

From the 8-bit D-latch flip-flop 25 and the 8-bit R / S flip-flop 31 carries 16-bit information to the shift register 33 via the line 32. This Shift register 33 accordingly has 16 parallel inputs for receiving the information 32 and 16 parallel, each output 34 for forwarding the data. Would be usable vir Commercial shift registers connected in parallel, 512 x 4, i. H. there can be 512 Clock steps are carried out. This means that z. B. the last 512 meters the distance covered by the motor vehicle is stored in the shift register 33 can be. If the data are taken via the parallel output 34, it closes a 16-bit data return line 35 the internal circuit in the shift register 33 (Data recirculation) so that the memory is not erased by mistake.

From the control unit and timing unit 23 leads via line 36 a control pulse on clock input 37 of the sliding registers 33. After every meter of travel, the shift register 33 is clocked one step further, until the 512 clocks (= 512 meters) have been shifted through the shift register. The control and TilfliLy unit 23 takes over the clocking of the counter 22 of the flip-flops 25, 31 and of the shift register 33. The lines are used for this 26 and 28, 36.

If you want to read out the information from the shift register 33, then the parallel outputs 34 of the shift register 33 the parallel inputs of a another 16-bit shift register.

38 supplied. This is done via an external clock line 39 the the shift register 38 is clocked through via the line 40.

The shift register 38 has a serial output 41 for reading out the data on. The 16 parallel inputs must therefore be read out before the shift register 38 receives new data via the parallel inputs 34. For this Adaptation, a counter 42 is provided via line 43 and the input 38 the shift register 33 only continues to clock when all 16 parallel inputs are read out serially in the shift register 38 via line 41.

So that both the control and timing unit 23 over the line 36 and the external clock input 39 via the line 4 to the shift register 33 An OR gate 44 is provided at the shift clock input 37. The administration 45 is used to clock the shift register 38 with respect to the parallel inputs.

In Fig. 2, the power supply of the system is shown schematically. The voltage supply shown schematically is supplied via a battery connection 46 47 the necessary operating voltage. A compressor 48 connected to this compares constantly the necessary voltage and shows the intact by means of a display 49 Operating status of the system. A buffer or emergency battery 50 is added, provided that the battery voltage 46 drops. This fault condition is shown on display 49 displayed.

Instead of one shift register, another one can of course also be used There are memories or a microcomputer combines all of the components.

In Fig. 3 such an alternative circuit of the ore is in accordance with the invention Principle reproduced.

The heart of the device according to the invention is the microcomputer 51 formed. This can either be called a "single-chip microcomputer" or as a Microprocessor with additional memories 52 (RAM, ROM), input / output modules 53, counter 54 and serial controller 55 and frequency divider 56. In the case of microcomputers with serial input and output, the serial controller can be implemented in software.

The microcomputer should be implemented in CMOS technology, uln the requirements for low performance and high temperature resistance to meet.

The program for the microprocessor 57 is in a ROM, PROM or EPROM 52 saved.

The shift register described in the exemplary embodiment according to FIG. 1 for the speed values and operating states is physically located in a RAM 52. At a distance of one meter, the division of the speed in 256 steps, 8 different state inputs and 256 meters of storable distance this results in a storage capacity of the RAM of at least 512 x 8 bits. For smaller ones Distance intervals and / or longer distances to be saved must be stored in the RAM accordingly be enlarged. This corresponds to the embodiment according to FIG. 1.

The frequency divider 56 of the microcomputer is used to divide the microprocessor clock required on a 10 ms cycle. The clock frequency is generated by a quartz. This 10 ms cycle is connected to the interrupt input of the microprocessor. The 10 ms cycle is used as a time base for calculating the current speed from, the speed proportional input frequency. This corresponds to the control and timing unit 23 according to FIG. 1.

The event counter 54 is used to count the input frequency while 10 ms.

The serial controller 55 is used to convert and output the data in a serial data stream for the connection of a printer.

The accident recorder is supplied with power by means of a Voltage regulator 58, which stabilizes the 12 volt network of the vehicle voltage to 5 volts. The output of the controller is fed to the electronics.

A battery is used as an emergency supply (if the 12 volt voltage fails) 59 is provided, which is continuously charged via a charging circuit 60. For safety should the battery z. B. be replaced every 4 years.

As in the exemplary embodiment according to FIG. 1, two types are also used here processed by digital signals. On the one hand, the speed must, on the other hand the other vehicle data are recorded.

The detection of the speed is done by generating a frequency proportional to the speed.

In automobiles with conventional speedometer display 61 connects a speedometer cable 62 a wheel or gear 63 with the speedometer.

For retrofitting or installing a digital driving writer's this speedometer cable 62 is separated and an angle encoder 64 is installed.

The implementation of a digital angle encoder can be achieved by a perforated disk attached to the speedometer cable. With one revolution of the speedometer cable rotates z. B.

the perforated disc once. An intermediate gear could be used for a greater resolution installed (one revolution of the speedometer cable = 10 revolutions of the perforated disc). The holes the perforated disk are scanned by means of an inductive encoder, whereby the disk must be made of metal. Alternatively, the holes can be closed with an infrared light barrier are scanned. The disk can be made of any material.

The conversion of the speed into a frequency results from the proportionality of the revolution of the speedometer cable or perforated disk per unit of time the driven speed. The number of holes in the perforated disc results the frequency per revolution.

The output signal of the angle encoder 64 generated in this way is shown in a signal conditioning 65 debounced with the aid of a Schmitt trigger and then limited to the level of the microcomputer supply.

As an alternative to the digital angular incremental encoder, a voltage Frequency converter can also be connected in parallel to the moving coil instrument of the speedometer. With automobiles With a digital speedometer display, the accident recorder can directly access the speedometer or to connected to the existing digital speedometer.

According to the embodiment shown in FIG. 3 shows the processing of additional signals such as ABS, brake, blinker, horn 66 etc. These signals are via a level adapter 67 (level converter) the Input / output 53 of the microcomputer 51 is supplied. These signals are from the microcomputer after z. B. scanned every meter of travel distance and with the speed data saved.

The realization of a printer to display the in the accident recorder Stored data is done by pressing a button on the accident recorder, whereby all data can be printed out. The data is read out via the serial controller 55 via a signal adapter 68 to the printer 69. Various printers can be used Opportunities.

The digital accident recorder can be connected to a thermal printer be. In this case, the accident recorder and printer are housed in one housing, which inside the vehicle such. B. a radio is installed. It can be a strip printer with 8 characters per line. The Ther- mopapier is allowed However, they change color at temperatures above 700 C at the earliest, in order to avoid the high temperatures withstand in the vehicle.

As an alternative to the thermal printer, a paper strip printer can also be used Ribbon and type wheel are installed. Such printers are used for small desktop computers used.

Alternatively, the data can also be displayed on a round paper disk will. The disc is driven by a motor. The recording takes place with a pen. To simplify the print control can be used for built-in printer a parallel interface (contrary to the block diagram) can be used.

When using an external printer, the serial output of the Accident recorder designed as a standardized V 24 / RS 232 or TTY interface. These serial interfaces are standardized worldwide. The data stored in RAM are converted into ASCII format by the microcomputer and output serially.

There is a plug at the exit of the accident recorder.

A commercially available printer with a serial interface can be connected to this connector be connected. Every police car could therefore have such a printer carry with you: nd take the values accordingly.

There is still the option of using all of the data the date and the current time. Date and time can be from The accident recorder's microcomputer is constantly calculated.

Claims (11)

Official designation: "Device for registration or Recording of data of a motor vehicle prior to an accident claims S Device for registering or recording data from a motor vehicle or the like. Such as speed, brake actuation, horn, light, blinker, etc. in front of you Accident ("Unfall-Schreiber") or for control, characterized in that the data to be recorded intermittently after a predetermined distance (s) and / or Time unit (t) recorded, digitized if necessary, and a microcomputer (51) and / or microprocessor (57) and / or a shift register (33) or the like and that the values stored in each case if necessary - like after an accident - are readable. 2. Apparatus according to claim 1, characterized in that the data the shift register (33) in z. B. sixteen parallel inputs (32) and fed in the encresponding outputs (34) are taken, with the Schlebereregister (33) e.g. B. 512 consecutive steps can take and that the data if necessary - like after an accident - in the middle] of a further downstream shift register (38) with parallel input (34) and serial output (41) through an external Clock (39) can be read out sina. 3. Apparatus according to claim 1 or 2, characterized in that the shift register (33) an 8-bit D-latch FliE for registering the speed signal (10) and an 8-bit R / S flip-flop for registering the remaining data (11 to 18) are connected upstream. 4. Apparatus according to claim 3, characterized in that the detection the speed according to equidistant distance intervals that the speed data (10) in an analog / frequency converter (19) into a digital frequency signal (20) converted, divided in a subsequent divider stage (21), an 8-bit binary counter (22) and then the 8-bit D-latch flip-flop (25), one of the Divider stage (21) downstream control and timing unit (23) the shift clock frequency (e.g. 1 cycle per meter) for the shift register (33), the one upstream of the shift register Flip-flops (25, 31) and the binary counter (22) take over. 5. Device according to one or more of the preceding claims 1 - 4, characterized in that the speed of the motor vehicle by means of an angle encoder (64) connected to the speedometer cable, e.g. B. a perforated disk with an inductive scanner or the like. 6. Device according to one of claims 1 to 3 or 4, marked by, that the other data such as actuation of the brake. (11), horn (13), indicator status (14, 15), the light (16 to 18), entry into force of the anti-lock braking system (12) etc. by means of a z. B. 8-bit level converter (29) (eight different signals) o. for supplying the 8-bit R / S flip-flop connected upstream of the shift register (33) (31) are processed. 7. Device according to one or more of claims 1 to 6, characterized characterized in that the voltage supply (47) for the accident recorder is an emergency battery (50) and a comparator (48) for voltage monitoring. 8. The device according to claim 1, characterized in that for detecting, Calculation, registration and output of the data to a microcomputer (51), in particular a single-chip microcomputer or an equivalent microprocessor (57) with additional Components such as RAM, ROM (52), input-output unit t5)., Counter (54), serial controller (55) etc. applies. 9. Apparatus according to claim 7 or 8, characterized in that the speed data supplied by a signal processor (65) to an event counter (54) for counting the input frequency and from there a microprocessor (57) with ROM memory (52) for user program and RAM memory (52) as a shift register for data storage. 10. Apparatus according to claim 7 or 8, characterized in that the microprocessor (57) a serial controller (5 for conversion and serial Data output is followed by a printer (69) via a signal adapter (68) is. 11. Device according to one or more of the preceding claims characterized in that the other data (66) such as brake signal, blinker, lighting etc. fed to the input / output (53) of the microcomputer via a level adapter (67) connected to the microprocessor (57)