JP2000076584A - Terminal equipment for vehicle operation management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal equipment for a vehicle operation management system capable of eliminating the influence of external noise from the detection data of an analog sensor for monitoring the state of a vehicle and managing the operation of the vehicle with continuity and accuracy. SOLUTION: The analog signals of the analog sensor 5 are A/D converted for every 10 msec and an inputted sampling value is compared with a maximum value and a minimum value among the already inputted sampling values, is updated and stored as the maximum value in a maximum value storage part 15 in the case of exceeding the maximum value and is updated and stored as the minimum value in a minimum value storage part 17 in the case of being smaller than the minimum value. For a total value stored in a total value storage part 16, after subtracting the maximum value and the minimum value stored in the maximum value storage part 15 and the minimum value storage part 17 at each 1 sec, the average value of the remaining eight sampling values is obtained in an average value output part 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal device used in a vehicle operation management system for managing the operation of vehicles used for distribution.

[0002]

2. Description of the Related Art FIG. 3 shows an overall configuration of a conventional vehicle operation management system by GPS used in the distribution industry. In this system, a terminal device A mounted on a vehicle and a management center B side. And a central computer 10 which is a central management device installed in the computer.

[0003] A terminal device A mounted on a vehicle receives a GPS signal emitted from a GPS satellite by a GPS antenna 1 and converts it into current position information by a GPS engine 2.
A microcomputer (hereinafter referred to as a microcomputer) 4 that constitutes an arithmetic processing means is configured to acquire the information from the acquired position information and various analog sensors 5 provided for monitoring the state of the vehicle. A central computer 10 such as a personal computer constituting a central management device provided in the management center B while fetching the state information of the vehicle to be stored into the storage device 3.
The information is transmitted to the management center B via the public telephone line 11 via the mobile communication means including the modem 6 and the mobile phone 7 in response to a request from the user. On the management center B side, information can be exchanged between the central computer 10 and the terminal device A through the ordinary telephone 8 and the modem 9 connected to the public telephone line 11, and the command of the request is transmitted to the terminal device. A, and information on the current position and the state information of the vehicle from the terminal device A can be received.

[0004]

The various analog sensors 5 provided outside the terminal device A include, for example, a temperature sensor for controlling the temperature of a cool box of a cool vehicle. The analog signal of the analog sensor 5 is taken in and A / D converted by an internal A / D function.

By the way, in the operation management of a refrigerator car, since the temperature management of the refrigerator is important, the temperature value of the refrigerator is continuously stored in the storage device 3 as log data.
In a vehicle, since an analog signal from the analog sensor 5 contains a large amount of noise due to ignition noise or the like, correct data may not be obtained, especially when the engine is started.

Further, it is difficult to obtain stable temperature information due to white noise constantly generated in the vehicle. To avoid this problem, eliminate sudden noise caused by turning on and off the ignition,
Both measures are needed to reduce stationary white noise. This applies not only to the temperature sensor but also to all analog sensors used to monitor the state of the vehicle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to eliminate the influence of disturbance noise from detection data of an analog sensor for monitoring the state of a vehicle, thereby improving continuity. An object of the present invention is to provide a terminal device for a vehicle operation management system capable of accurately managing the operation of a vehicle.

[0008]

According to the first aspect of the present invention, G
The current position detecting means of the mounted vehicle using the PS, an analog sensor for detecting the state of the vehicle, and the current position of the vehicle is obtained from the detection data of the current position detecting means, and the state of the vehicle is detected by the detection data of the analog sensor. A terminal for a vehicle operation management system comprising at least arithmetic processing means for obtaining, and mobile communication means for notifying the central management device of information on the current position of the vehicle and information on the state of the vehicle obtained by the arithmetic processing means. The apparatus further includes data conversion means for performing data processing for eliminating the influence of disturbance noise before taking in the detection data from the analog sensor into the arithmetic processing means. The data after the data conversion by the data conversion means is detected by the analog sensor. It is characterized in that the data is taken into arithmetic processing means as data.

According to a second aspect of the present invention, in the first aspect of the present invention, the data conversion means samples the analog signal output from the analog sensor at predetermined time intervals, and obtains a plurality of sampled values obtained within a predetermined period. The maximum value,
The method is characterized in that the minimum value is removed and the average value of the remaining sampling values is output to the arithmetic processing means as detection data after data conversion.

According to a third aspect of the present invention, in the second aspect of the present invention, the data conversion means is means for setting a final number of the sampling values for taking the average value to a power of two.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the analog sensor is a temperature sensor for a cool box.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in FIGS.

In this embodiment, as shown in FIG. 2, a smoothing data processing unit 12 is provided as a data conversion means as a data conversion means before the analog signal from the analog sensor 5 is taken into the microcomputer. Do.

As described above, the noise generated in the vehicle includes a noise having a very large sudden level when the ignition is turned on and off, and a stationary noise having a relatively small level called white noise.

Therefore, the smoothed data processing unit 12 removes a large level of ignition noise,
A function to perform data processing so that this signal can be ignored when a temporarily excessive level signal is generated, and to obtain stability against the signal after temporarily removing the excessive level signal. It has a function to add a smoothing process.

Another configuration of the terminal device A according to the present embodiment is similar to that of the conventional example, and information is transmitted and received between the central computer 10 of the management center B and the mobile communication means including the modem 6 and the mobile phone 7. The microcomputer 4 constituting the arithmetic processing means obtains the current position from data from a GPS receiving device comprising the GPS antenna 1 and the GPS engine unit 2 and obtains a modem 6 in accordance with what is called from the management center side. And transmitted to the management center B via the mobile phone 7. The management center B side has a public telephone line 11,
Information can be exchanged between the central computer 10 and the terminal device A by the ordinary telephone 8 and the modem 9.

The information from the various analog sensors 5 is stored in the storage device 3 of the microcomputer 4 after the data smoothing processing unit 12 performs noise removal processing. Microcomputer 4
The data after the smoothing process stored in the management center B
Is transmitted to the management center B via the modem 6 and the mobile phone 7 at any time in response to a request from the central computer 10.

Next, the operation of the smoothing processing section 12, which is the main configuration of the present invention, will be described with reference to FIG.

First, in FIG.
This shows a case in which a temperature sensor for detecting the temperature of a cool box of a food-cooled car is used, and the analog signal of the analog sensor 5 including the temperature sensor always outputs a signal of an analog signal containing noise. I have.

The smoothing processing unit 12 includes a 100 msec timer 13, an A / D input processing unit 14, a maximum value storage unit 15, a total value storage unit 16, a minimum value storage unit 17, and a 1 second timer 1
8. CPU that realizes average value output unit 19 by software
A / A
The D input processing unit 14 receives the start signal from the 100 msec timer 13 and receives the analog sensor 5 every 100 msec.
Is converted to a digital signal and output to the total value storage unit 16.

The total value storage unit 16 compares the input value with the maximum value and the minimum value of the input sampling values. Since the maximum value and the minimum value are not stored in the maximum value storage unit 15 and the minimum value storage unit 17 at the time of the first sampling, respectively, the first sampling values are stored in the storage units 15 and 17 as the minimum value and the maximum value, respectively. Is done. The second and subsequent sampling values are stored in the storage units 15 and 17.
Are compared with the maximum value and the minimum value stored in the storage unit. If the sampling value exceeds the stored maximum value, the maximum value storage unit 15 updates and stores the sampling value as the maximum value. I do. Similarly, when the sampling value is smaller than the stored minimum value, the minimum value storage unit 17 updates and stores the sampling value as the minimum value. Then, the total value storage unit 16 adds and stores the input sampling values.

The total value stored in the total value storage unit 16 is
At the time, the maximum value storage unit 15, the minimum value storage unit 17
After subtracting the maximum value and the minimum value stored in the average value output unit 19. At this time, the number of sampling values is 1000 msec / 100 msec = 10 samples. As a result of subtracting the maximum value and the minimum value, the average value is obtained by averaging the remaining eight sampling values in the average value output unit 19. The average value of the eight samples is obtained by dividing the total value after subtracting the maximum value and the minimum value by the number of samples 8. By calculating the number of samples 8 as a power of 2, the average value can be calculated. This is obtained by shifting the total value to the right by 3 bits, thereby reducing the load on the CPU. Note that the storage contents of the storage units 15 to 17 are initialized each time the processing is completed by the command output of the 1-second timer 18.

The smoothed data obtained in this way is taken into the microcomputer 4 and is continuously stored in the storage device 3 as log data, and the stored data is used in response to a request from the management center B. Depending on the management center side B
Will be sent to

[0024]

According to the first aspect of the present invention, there is provided a terminal device for a vehicle operation management system configured as described above, wherein the data for eliminating the influence of disturbance noise before the detection data from the analog sensor is taken into the arithmetic processing means. Since data conversion means for performing processing is provided, and the data after the data conversion by the data conversion means is taken into the arithmetic processing means as detection data of the analog sensor, noise caused by turning on / off the ignition mixed in the analog signal of the analog sensor is reduced. The influence of disturbance noise such as white noise can be eliminated and taken into the arithmetic processing means, so that there is an effect that the state management of the vehicle can be performed based on state information having stable continuity and accuracy.

According to a second aspect of the present invention, in the first aspect of the present invention, the data conversion means samples the analog signal output from the analog sensor at predetermined time intervals, and obtains a plurality of sampled values obtained within a predetermined period. Since the maximum value and the minimum value are removed and the average value of the remaining sampling values is output to the arithmetic processing means as detection data after data conversion, data obtained by eliminating the influence of disturbance noise can be obtained by a simple arithmetic processing. Can be.

According to a third aspect of the present invention, in the second aspect of the present invention, the data conversion means is means for setting the final number of the sampling values for taking the average value to a power of two.
When U is used, the load on the CPU can be reduced.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the analog sensor is a temperature sensor for a cool box. Temperature control can be ensured.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram for explaining the operation of a smoothing processing unit according to an embodiment of the present invention.

FIG. 2 is an overall configuration diagram of a vehicle operation management system using the above.

FIG. 3 is an overall configuration diagram of a conventional vehicle operation management system.

[Explanation of symbols]

 Reference Signs List 5 analog sensor 12 smoothing processing section 13 100 msec timer 14 A / D input processing section 15 maximum value storage section 16 total value storage section 17 minimum value storage section 18 1 sec timer 19 average value output section

Claims (4)

[Claims] 1. A current position detecting means of a mounted vehicle using a GPS, an analog sensor for detecting a state of the vehicle, a current position of the vehicle is acquired from detection data of the current position detecting means, and detection data of the analog sensor is obtained. And a mobile communication unit for notifying the central management unit of the information on the current position of the vehicle and the information on the state of the vehicle acquired by the arithmetic processing unit. In the terminal device for operation management system,
Before taking the detection data from the analog sensor into the arithmetic processing means, the data conversion means for performing data processing for eliminating the influence of disturbance noise is provided, and the data converted by the data conversion means is calculated as the detection data of the analog sensor. A terminal device for a vehicle operation management system, wherein the terminal device is incorporated in processing means. 2. A data conversion means which samples an analog signal output from an analog sensor at a predetermined time interval, and removes a maximum value and a minimum value of a plurality of sampled values obtained within a predetermined period to obtain a remaining value. 2. The terminal device for a vehicle operation management system according to claim 1, wherein an average value of the sampling values is output to the arithmetic processing unit as detection data after data conversion. 3. The terminal device for a vehicle operation management system according to claim 2, wherein the data conversion means is means for setting a final number of the sampling values taking the average value to a power of two. 4. The terminal device for a vehicle operation management system according to claim 1, wherein the analog sensor is a temperature sensor for a refrigerator.