Transport vehicle stoppage determination device

Abstract

To provide a stop determination device which can highly accurately determine the stop state without monitoring a plurality of types of signals even when a carrier vehicle is the determination object.SOLUTION: When a forklift stops from the advancement state or the retreat state, a stop determination device monitors a signal of acceleration in the vehicle body front-rear direction, detects a peculiar G value behavior pattern and uses it for determination of stop. In a region of a pre-stop behavior BP1-A or the like, after a behavior in the first state that starts on the side on which the G value in the X-axis direction is minus with respect to a Gx reference value Gx0, the stop determination device detects a behavior in the second state that starts on the side on which the G value is plus with respect to the Gx reference value Gx0, and determines stop after the G value in the X-axis direction converges to the Gx reference value Gx0 and becomes stable. In the case of retreat, the stop determination device monitors the inclination of a speed that reduces from the side on which the G value in the X-axis direction is plus. The stop determination device utilizes a parameter prepared for each vehicle type.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a stoppage determination device for a transport vehicle that can be used to automatically determine the stoppage state of a transport vehicle such as a forklift. [Background technology]

[0002] For example, it is very important to automatically determine whether a vehicle, such as a passenger car, or a transport vehicle, such as a forklift, is stationary. In addition, a device for determining whether a vehicle is stationary typically uses multiple signals, such as an acceleration value, a brake signal, and a vehicle speed signal, to improve the accuracy of the determination.

[0003] On the other hand, the vehicle monitoring system of Patent Document 1 shows that the vehicle's operating state is determined to be one of a stationary state where the vehicle is stationary, a traveling state where the vehicle is traveling, and a transporting state where the vehicle is being transported, based on acceleration information from an acceleration sensor installed in a general vehicle. Furthermore, it shows that state information other than the vehicle's operating state is obtained based on the determined operating state and acceleration information.

[0004] Furthermore, Patent Document 2 discloses a technique for accurately determining when a forklift has stopped moving. Specifically, it discloses that a data recorder acquires the forklift's speed and an identification signal indicating whether the forklift is moving forward or backward, and when the combination of this speed and direction of movement satisfies a predetermined condition, it determines that the forklift has stopped moving regardless of the detection results of sensors equipped on the forklift, records operation data including this determination result on a recording medium, and analyzes this recorded data with an operation management device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-117423 [Patent Document 2] Patent No. 4908654 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the behavior of acceleration detected on a transport vehicle such as a forklift is significantly different from that of a general vehicle such as a passenger car, so the technology of Patent Document 1 cannot be used as is for applications involving transport vehicles.

[0007] Furthermore, when using the technology of Patent Document 2, the back signal must be monitored along with the acceleration signal to determine the direction of travel of the forklift. This increases the processing load on the ECU (electronic control unit) that makes the determination. Furthermore, the effort required for connecting the on-board device to the vehicle increases.

[0008] Furthermore, the behavior of the acceleration actually detected is greatly affected by differences in vehicle type (e.g., battery-powered vehicle / engine vehicle), differences in vehicle size, and unevenness of the road surface on which the vehicle is traveling. Therefore, if a judgment is made by simply comparing the acceleration value with a threshold value, it is easy to erroneously judge the vehicle to be stopped.

[0009] The present invention has been made in consideration of the above-mentioned circumstances, and its purpose is to provide a stoppage judgment device for a transport vehicle that can accurately judge the stopped state without monitoring multiple types of signals, even when the transport vehicle is the target of judgment. [Means for solving the problem]

[0010] The above object of the present invention can be achieved by the following configuration.

[0011] A stop determination device that determines whether a transport vehicle has stopped based on a measurement value acquired by a predetermined acceleration sensor installed on the transport vehicle, The acceleration value in the vehicle traveling direction acquired by the acceleration sensor is set to a predetermined reference value. changes in the negative direction compared to a first state detection unit that detects a first state; Regarding the acceleration value in the vehicle traveling direction acquired by the acceleration sensor, changes in the positive direction compared to a second state detection unit that detects a second state; based on the second condition being detected after the first condition being detected, a final determination unit that determines whether the transport vehicle has stopped; A stop determination device for a transport vehicle. [Effects of the Invention]

[0012] According to the transport vehicle stop determination device of the present invention, even when a transport vehicle is the object of determination, it is possible to determine the stopped state with high accuracy simply by monitoring the measured values acquired by the acceleration sensor. That is, by detecting a characteristic acceleration change pattern resulting from a combination of the first state and the second state, it is possible to determine with high accuracy whether the transport vehicle is stopped.

[0013] The present invention has been briefly described above. The details of the present invention will become clearer by reading the following detailed description of the invention (hereinafter referred to as "embodiments") with reference to the accompanying drawings. [Brief explanation of the drawings]

[0014] [Figure 1] 1(a), 1(b), and 1(c) are time charts showing examples of changes in acceleration in each axial direction detected when vehicles of different models are moving forward. [Figure 2] 2(a), 2(b), and 2(c) are time charts showing examples of changes in acceleration in each axial direction detected when vehicles of different models are reversed. [Figure 3] FIG. 3 is a flowchart showing a processing procedure for determining a stopped state when moving forward. [Figure 4] FIG. 4 is a block diagram showing an example of the functional configuration of the stop determination vehicle-mounted device. [Figure 5] FIG. 5 is a block diagram showing an example of the configuration of the performance data management device. DETAILED DESCRIPTION OF THE INVENTION

[0015] Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

[0016] First, an example of a change in acceleration of the object to be monitored will be described when a forklift truck moves forward.

[0017] Figures 1(a), 1(b), and 1(c) show examples of changes in acceleration in the X, Y, and Z axes detected when different types of forklift vehicles move forward. In each figure, the horizontal axis represents time (seconds) and the vertical axis represents acceleration values. The X axis represents the front-to-back direction of the vehicle, the Y axis represents the left-to-right direction of the vehicle, and the Z axis represents the up-to-down direction. Differences in vehicle types correspond to differences between battery-powered and engine-powered vehicles, as well as differences in vehicle size.

[0018] Figure 1(a) shows the time series changes in acceleration in three axes detected by an acceleration sensor installed on a forklift of "Vehicle Type A," namely, the X-axis G (acceleration) value DXG-A, the Y-axis G value DYG-A, and the Z-axis G value DZG-A.

[0019] Similarly, Figure 1(b) shows the time series changes in the X-axis G-value DXG-B, the Y-axis G-value DYG-B, and the Z-axis G-value DZG-B for a forklift of "Vehicle Type B." Also, Figure 1(c) shows the time series changes in the X-axis G-value DXG-C, the Y-axis G-value DYG-C, and the Z-axis G-value DZG-C for a forklift of "Vehicle Type C."

[0020] 1(a) to 1(c), each stoppage determination section Asp represents a section in which it can be determined that the forklift being monitored is stopped. In other words, the stoppage determination section Asp corresponds to a state in which it should be recognized that the forklift has stopped moving in the forward / backward and left / right directions and that the forks and other parts have also stopped moving up and down.

[0021] Therefore, when automatically determining whether a forklift in a forward moving state has actually stopped, it is important to be able to correctly determine whether it is within each of the stoppage determination sections Asp in Figures 1(a) to 1(c).

[0022] The stop start point tss in Figures 1(a) to 1(c) represents the timing at which the conditions for starting the automatic determination process for the forklift's stop are satisfied. Also, the pre-stop behaviors BP1-A, BP1-B, and BP1-C in Figures 1(a) to 1(c) represent the regions of characteristic behavior patterns that occur in the X-axis acceleration signal Gx (DXG-A, DXG-B, and DXG-C) after the stop start point tss and before the transition to the stop determination section Asp.

[0023] In the example shown in FIG. 1(a), in the time domain of pre-stop behavior BP1-A, a "first state" occurs in which the X-axis direction G value DXG-A changes in the negative direction (opposite to the direction of travel) compared to the Gx reference value Gx0. After the "first state," a "second state" occurs in which the X-axis direction G value DXG-A changes in the positive direction (the same direction as the direction of travel) compared to the Gx reference value Gx0. After the "second state," the X-axis direction G value DXG-A converges to a state where it matches the Gx reference value Gx0. After the X-axis direction G value DXG-A matches the Gx reference value Gx0, the amount of fluctuation in the X-axis direction G value DXG-A is relatively small within the stop determination section Asp.

[0024] On the other hand, in the example shown in Figure 1(b), in the time domain of the pre-stop behavior BP1-B, the X-axis G value DXG-B converges to a state where it matches the Gx reference value Gx0 after passing through the "first state" and the "second state", just like the pre-stop behavior BP1-A in Figure 1(a). Note that the Gx reference value Gx0 in Figure 1(b) may differ from the Gx reference value Gx0 in Figure 1(a).

[0025] Furthermore, in the example shown in Figure 1(c), in the time domain of the pre-stop behavior BP1-C, the X-axis G value DXG-C converges to a state where it matches the Gx reference value Gx0 after passing through the "first state" and the "second state," just like the pre-stop behavior BP1-A in Figure 1(a). Note that the Gx reference value Gx0 in Figure 1(c) may differ from the Gx reference value Gx0 in Figure 1(a).

[0026] In other words, the behavior patterns of the X-axis G values in the pre-stop behaviors BP1-A, BP1-B, and BP1-C are very similar to one another, so by recognizing these characteristic behavior patterns, it becomes possible to accurately determine whether the forklift has stopped when it transitions from a forward movement state to a stop.

[0027] For example, if the forklift is an engine-powered vehicle, the influence of engine vibrations will be reflected in the X-axis G value as a relatively small behavior even when the vehicle is stopped. Furthermore, the influence of unevenness on the road surface on which the forklift is traveling will also be reflected in the X-axis G value. Therefore, when determining whether a forklift is stopped, it is necessary to eliminate the influence of noise, such as vibrations generated by the vehicle itself and vibrations caused by the road surface.

[0028] Next, an example of a change in acceleration of the object to be monitored when a forklift is moving backward will be described.

[0029] Figures 2(a), 2(b), and 2(c) show examples of changes in acceleration in the X, Y, and Z axes detected when different types of forklift vehicles are moving backward.

[0030] Figure 2(a) shows the time series changes in the acceleration in three axes detected by an acceleration sensor installed on a forklift of "Vehicle Type B," namely, the X-axis G value DXG-B, the Y-axis G value DYG-B, and the Z-axis G value DZG-B.

[0031] Similarly, Figure 2(b) shows the time series changes in the X-axis G-value DXG-B, the Y-axis G-value DYG-B, and the Z-axis G-value DZG-B for a forklift of "Vehicle Type B." Also, Figure 2(c) shows the time series changes in the X-axis G-value DXG-A, the Y-axis G-value DYG-A, and the Z-axis G-value DZG-A for a forklift of "Vehicle Type A."

[0032] 2(a) to 2(c), each stoppage determination section Asp represents a section in which it can be determined that the forklift being monitored is stopped. In other words, the stoppage determination section Asp corresponds to a state in which it should be recognized that the forklift has stopped moving in the forward / backward and left / right directions and that the forks and other parts have also stopped moving up and down.

[0033] Therefore, when automatically determining whether a forklift in a backward movement has actually stopped, it is important to be able to correctly determine whether it is within each of the stoppage determination zones Asp in Figures 2(a) to 2(c).

[0034] The stop start point tss in Figures 2(a) to 2(c) represents the timing at which the conditions for starting the automatic determination process for the forklift's stop are satisfied. Also, the pre-stop behaviors BP2-A, BP2-B, and BP2-C in Figures 2(a) to 2(c) represent the regions of characteristic behavior patterns that occur in the X-axis acceleration signal Gx (DXG-A, DXG-B, and DXG-C) after the stop start point tss and before the transition to the stop determination section Asp.

[0035] 2(a), in the time domain of pre-stop behavior BP2-A, the X-axis direction G-value DXG-B decreases at a gradual slope from the positive direction compared to the Gx reference value Gx0, and converges to a state where it matches the Gx reference value Gx0. Furthermore, after the X-axis direction G-value DXG-B matches the Gx reference value Gx0, the amount of fluctuation of the X-axis direction G-value DXG-B is relatively small within the stop determination section Asp.

[0036] Furthermore, in both time domains of pre-stop behavior BP2-B in Figure 2(b) and pre-stop behavior BP2-C in Figure 2(c), the X-axis direction G value decreases at a gradual slope from the positive direction compared to the Gx reference value Gx0, converging to a state that matches the Gx reference value Gx0, just as in the example of Figure 2(a).

[0037] In other words, the behavior patterns of the X-axis G values in the pre-stop behaviors BP2-A, BP2-B, and BP2-C are very similar to one another, so by recognizing these characteristic behavior patterns, it becomes possible to accurately determine whether the forklift has stopped when it transitions from a reversing state to a stop.

[0038] Next, a processing procedure for determining a stopped state when the vehicle is moving forward will be described.

[0039] Fig. 3 shows a specific example of a processing procedure for automatically determining when a forklift has stopped from a forward movement.

[0040] That is, characteristic behavior patterns such as pre-stop behaviors BP1-A, BP1-B, and BP1-C shown in Figures 1(a) to 1(c) can be detected according to the procedure shown in Figure 3, and automatic stop determination can be performed. The operation when the stop determination vehicle-mounted device 10 (described later) executes the procedure shown in Figure 3 will be described below.

[0041] The stop determination vehicle-mounted device 10 averages the G values in the X-axis direction output from the acceleration sensor using an even number of values sampled at mutually shifted timings (S11).

[0042] The stop determination vehicle-mounted device 10 monitors the value of the acceleration signal Gx obtained as a result of the averaging process, and determines in S12 whether or not the acceleration signal Gx has detected a point on the negative side where it is smaller than the Gx reference value Gx0, i.e., the point of the above-mentioned "first state." If the "first state" point is detected, the process proceeds to the next step S13.

[0043] The stop determination vehicle-mounted device 10 monitors the value of the acceleration signal Gx obtained as a result of the averaging process, and determines in S13 whether or not a point on the positive side where the acceleration signal Gx is greater than the Gx reference value Gx0, i.e., the point of the above-mentioned "second state", has been detected. If the "second state" point has been detected, the process proceeds to the next step S14.

[0044] The stop determination vehicle-mounted device 10 monitors the value of the acceleration signal Gx obtained as a result of the averaging process, and determines in S14 whether or not the point at which the acceleration signal Gx substantially matches the Gx reference value Gx0, i.e., whether or not the convergence of the change in the G value has been detected. If the convergence of the change in the G value has been detected, the process proceeds to the next step S15.

[0045] After detecting the convergence of the change in the G value, the stop determination vehicle-mounted device 10 starts counting down a certain time in S15 to check whether a stable state has continued for a certain time without any major behavior.

[0046] The vehicle-mounted stop determination device 10 monitors the value of the acceleration signal Gx that has passed through a predetermined filter in S16 until the end of the countdown for a certain period of time, and determines whether or not a behavior exceeding a predetermined threshold has occurred. Here, the filter has the function of removing noise components due to environmental factors, such as vibrations of the engine while stopped and fluctuations in the G value caused by unevenness of the road surface, from the acceleration signal Gx.

[0047] If a behavior exceeding the predetermined threshold is detected in S16, the stop determination vehicle-mounted device 10 returns to the process of S12 and repeats the above process.

[0048] If the countdown ends in S17 without detecting any significant behavior during the predetermined time, the stop determination vehicle-mounted device 10 executes a stop determination. That is, the stop determination vehicle-mounted device 10 automatically recognizes in S17 that the vehicle has entered the stop determination section Asp shown in Figures 1(a) to 1(c).

[0049] The stop determination vehicle-mounted device 10 monitors the state of the acceleration signal Gx in S18 and determines the direction of forward / reverse movement.

[0050] In other words, the stop determination vehicle-mounted device 10 can detect characteristic behavior patterns in the pre-stop behaviors BP1-A, BP1-B, and BP1-C in Figures 1(a) to 1(c) in S12 to S14 shown in Figure 3 and then make a stop determination.

[0051] Next, the configuration of the vehicle-mounted stop determination device will be described.

[0052] An example of the functional configuration of the vehicle-mounted stop determination device 10 is shown in FIG. The vehicle-mounted stop determination device 10 shown in Fig. 4 is installed on a forklift truck as an on-board device. The acceleration sensor 11 provided in the vehicle-mounted stop determination device 10 has a function of detecting acceleration in at least the X-axis direction, which corresponds to the front-to-rear direction of the forklift. Note that a sensor capable of detecting acceleration in three axes, the X-axis, Y-axis, and Z-axis directions, may also be used as the acceleration sensor 11.

[0053] The vehicle-mounted stop determination device 10 can determine whether the forklift is stopped or not and can determine the direction of forward / reverse movement based on the acceleration in the X-axis direction detected by the acceleration sensor 11. The vehicle-mounted stop determination device 10 shown in Fig. 4 also includes a function corresponding to the processing procedure shown in Fig. 3.

[0054] In the example shown in Fig. 4, the stop determination vehicle-mounted device 10 includes an averaging processing unit 12, a stop start detection unit 13, a negative side acceleration detection unit 14, a positive side acceleration detection unit 15, a Gx0 point detection unit 16, a Gx0 behavior monitoring unit 17, a vehicle-specific correction database (DB) 18, a filter processing unit 19, a G value gradient determination unit 20, a stop time determination unit 21, and a forward / backward detection unit 22. Each of these functions can be realized by hardware and software of a microcomputer (not shown) included in the stop determination vehicle-mounted device 10. Of course, each of the functions in Fig. 4 may also be realized by using an electronic circuit such as a dedicated logic circuit.

[0055] The averaging processor 12 processes the time-series data of the acceleration in the X-axis direction output by the acceleration sensor 11, performs averaging, and outputs the result as an acceleration signal Gx.

[0056] The stop start detection unit 13 can detect the stop start point tss shown in Figures 1 and 2 based on the acceleration signal Gx. When the stop start detection unit 13 detects the stop start point tss, it outputs a stop start signal SGs.

[0057] The negative acceleration detection unit 14 can detect the above-mentioned "first state" by comparing the G value of the acceleration signal Gx with the Gx reference value Gx0 in accordance with the stop start signal SGs output by the stop start detection unit 13. That is, similar to step S12 shown in Fig. 3, a point in the pre-stop behavior BP1 where the G value is on the negative side with respect to the Gx reference value Gx0 is detected as the "first state."

[0058] After the negative acceleration detection unit 14 detects the "first state," the positive acceleration detection unit 15 compares the G value of the acceleration signal Gx with the Gx reference value Gx0 to detect the "second state." That is, similar to step S13 shown in Fig. 3, a point in the pre-stop behavior BP1 where the G value is on the positive side of the Gx reference value Gx0 is detected as the "second state."

[0059] After the positive side acceleration detection unit 15 detects the "second state," the Gx0 point detection unit 16 compares the G value of the acceleration signal Gx with the Gx reference value Gx0, and can detect the point at which the G value converges to a state that is approximately equal to the Gx reference value Gx0.

[0060] The Gx0 behavior monitoring unit 17 has a function of monitoring the behavior of the acceleration signal Gx in a stopped state after the G value has converged to a state where it is approximately equal to the Gx reference value Gx0. In addition, to avoid the influence of noise components such as engine vibrations that occur even when the forklift is stopped, the Gx0 behavior monitoring unit 17 monitors the filtered output acceleration Gxf output by the filtering processing unit 19.

[0061] When the Gx0 behavior monitoring unit 17 detects a relatively large behavior of the filter output acceleration Gxf, the detection states of the negative side acceleration detection unit 14, the positive side acceleration detection unit 15, and the Gx0 point detection unit 16 are reset by the reset signal RST output by the Gx0 behavior monitoring unit 17.

[0062] The vehicle-specific correction database 18 stores various vehicle-specific parameters, including the Gx reference value Gx0, the filter coefficient K1, and the G-value gradient threshold value K2, in advance as a database configured in non-volatile memory. The vehicle-specific correction database 18 can output appropriate parameters according to the size of the forklift equipped with the stop determination on-board device 10, whether it is an engine vehicle or a battery vehicle, etc. Furthermore, an appropriate value is selected for the Gx reference value Gx0 according to the forward / reverse direction of the forklift.

[0063] The filter processing unit 19 filters the acceleration signal Gx in accordance with a filter coefficient K1 specific to each model of forklift to generate a filter output acceleration Gxf. For example, if the forklift is an engine vehicle, the engine will be in a stable idling state while stopped, so filtering is performed to remove vibration frequency components selected in accordance with the idling rotation speed from the acceleration signal Gx.

[0064] The G-value gradient determination unit 20 has a function of detecting characteristic G-value behavior patterns that occur when the forklift transitions from a backing up state to a stopped state, such as pre-stop behaviors BP2-A, BP2-B, and BP2-C shown in Fig. 2. That is, in this behavior pattern, the G-value of the acceleration signal Gx gradually decreases from a state where it is on the positive side of the Gx reference value Gx0, and converges to the Gx reference value Gx0. Therefore, the G-value gradient determination unit 20 detects the rate of change when the G-value of the acceleration signal Gx decreases from the positive side of the Gx reference value Gx0, compares the gradient of the rate of change with the G-value gradient threshold K2, and outputs the determination result.

[0065] The stop time determination unit 21 has a function of determining whether a state in which the Gx0 behavior monitoring unit 17 does not detect any significant behavior continues for a certain period of time or more after a characteristic G-value behavior pattern in the pre-stop behavior BP1 or BP2 is detected and the G-value converges to the Gx reference value Gx0. Therefore, the stop determination output C1 output by the stop time determination unit 21 indicates whether or not the vehicle is in the stop determination section Asp in FIG. 1 or 2.

[0066] The forward / backward detection unit 22 detects whether the forklift is moving forward or backward based on the behavior of the acceleration signal Gx and the gradient of the G-value decrease detected by the G-value gradient determination unit 20. When the forklift transitions from forward to stopped, the forward / backward detection unit 22 determines the direction of movement after the stop time determination unit 21 has completed its determination. Also, when the forklift is moving backward, the forward / backward detection unit 22 monitors the gradient of the G-value decrease in the positive direction, and if the gradient does not drop completely to the Gx reference value Gx0, the forward / backward detection unit 22 detects "forward."

[0067] The vehicle-mounted stop determination device 10 shown in Fig. 4 can provide a stop determination output C1 and a direction determination output C2 to an external forklift management device 30. The forklift management device 30 is, for example, a drive recorder or data recorder that automatically records performance data on the operating status of the forklift, or a device for managing the safety of the forklift and providing driving support. The vehicle-mounted stop determination device 10 and the forklift management device 30 may be integrated into one device.

[0068] Next, the configuration of the performance data management device will be described.

[0069] An example of the configuration of the performance data management device 40 is shown in Fig. 5. The performance data management device 40 shown in Fig. 5 can be incorporated into the vehicle-mounted stop determination device 10, or can be connected to the vehicle-mounted stop determination device 10 as a function of the forklift management device 30.

[0070] The performance data management device 40 includes a performance data acquisition unit 41, a vehicle-specific performance database 42, and a correction value addition processing unit 43. The performance data acquisition unit 41 can automatically acquire performance data 41a generated inside the stop judgment vehicle-mounted device 10 and record it in the vehicle-specific performance database 42.

[0071] The performance data 41a includes information indicating the vehicle type and size of the forklift equipped with the stop determination on-board device 10, and performance data such as the acceleration signal Gx when various triggers are generated in the stop determination on-board device 10. For example, a trigger is generated when predetermined conditions are satisfied in each of the stop start detection unit 13, the negative side acceleration detection unit 14, the positive side acceleration detection unit 15, the Gx0 point detection unit 16, the Gx0 behavior monitoring unit 17, the G value gradient determination unit 20, the stop time determination unit 21, and the forward / backward detection unit 22. Then, the type of the corresponding trigger and the performance data such as the acceleration signal Gx at that time are imported from the stop determination on-board device 10 to the performance data acquisition unit 41 and stored in the vehicle-specific performance database 42.

[0072] The correction value addition processing unit 43 automatically analyzes the latest performance data stored in the vehicle-specific performance database 42, and adds correction data to the vehicle-specific correction database 18 to make the judgment operation of the stop judgment vehicle-mounted device 10 more appropriate.

[0073] As described above, the vehicle-mounted stop determination device 10 according to this embodiment can determine whether the forklift is stopped or not simply by monitoring the acceleration in the X-axis direction output by the acceleration sensor 11. In other words, there is no need to acquire various vehicle information from the forklift. This simplifies the installation work when retrofitting the vehicle-mounted stop determination device 10 to a forklift.

[0074] Furthermore, when the forklift transitions from a forward movement state to a stop, the system recognizes characteristic G-value behavior patterns such as the pre-stop behavior BP1-A shown in Figures 1(a) to 1(c), so it is possible to determine with high accuracy whether the forklift is in a stopped state simply by monitoring the acceleration in the X-axis direction.

[0075] Furthermore, when a forklift moves from a backward state to a stop, the system recognizes characteristic G-value behavior patterns such as the pre-stop behavior BP2-A shown in Figures 2(a) to 2(c), so it is possible to determine with high accuracy whether the forklift is in a stopped state simply by monitoring the acceleration in the X-axis direction.

[0076] Furthermore, by using the vehicle-specific correction database 18, the stop determination vehicle-mounted device 10 can use appropriate parameters for determination that take into account differences in the model and size of the forklift, making it easy to prevent erroneous determination.

[0077] In addition, by using the filter processing unit 19, the stop determination vehicle-mounted device 10 can easily avoid falsely detecting fluctuations in the G value caused by engine vibrations while the vehicle is stopped or unevenness in the road surface as the behavior of a forklift.

[0078] The present invention is not limited to the above-described embodiments, and can be appropriately modified, improved, etc. Furthermore, the material, shape, size, number, location, etc. of each component in the above-described embodiments are arbitrary and not limited as long as they can achieve the present invention.

[0079] For example, in the above embodiment, only the case where the stop determination vehicle-mounted device 10 determines the stop of a forklift has been described, but the stop determination vehicle-mounted device 10 can also be used when a transport vehicle other than a forklift is to be monitored.

[0080] The following [1] to [5] briefly summarize and list the characteristic features of the above-mentioned stop determination device for a transport vehicle. [1] A stop determination device that determines whether a transport vehicle has stopped based on measurements acquired by a predetermined acceleration sensor installed on the transport vehicle, a first state detection unit (S12, negative acceleration detection unit 14) that detects a first state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor (11) starts at a negative value relative to a predetermined reference value (Gx reference value Gx0); a second state detection unit (S13, plus-side acceleration detection unit 15) that detects a second state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor starts at a plus value relative to the reference value; a final determination unit (S14 to S17, a Gx0 point detection unit 16, a Gx0 behavior monitoring unit 17, and a stop time determination unit 21) that determines whether the transport vehicle should be stopped based on the detection state of the first state detection unit and the detection state of the second state detection unit; A stop determination device for a transport vehicle.

[0081] According to the stoppage determination device for a transport vehicle having the configuration [1] above, it is possible to detect a G-value behavior pattern specific to a transport vehicle, such as the pre-stop behavior BP1-A shown in Figures 1(a) to 1(c), and correctly determine the stopped state of the transport vehicle.

[0082] [2] A forward / backward direction detection unit (forward / backward detection unit 22) is provided to distinguish between forward and backward movement of the transport vehicle, The final determination unit reflects the difference between forward and backward movement of the transport vehicle in the difference in the determination conditions. The stop determination device for a transport vehicle according to [1] above.

[0083] According to the stoppage determination device for a transport vehicle having the configuration [2] above, it is possible to correctly detect both the G-value behavior pattern that is specific to when the transport vehicle transitions from forward movement to a stoppage and the G-value behavior pattern that is specific to when the transport vehicle transitions from backward movement to a stoppage.

[0084] [3] A downward slope detection unit (G value slope determination unit 20) is provided to detect the slope of the change in the acceleration value in the vehicle traveling direction acquired by the acceleration sensor, the slope of the change being downward from a positive direction from a predetermined reference value (Gx reference value Gx0). The stop determination device for a transport vehicle according to [1] or [2] above.

[0085] According to the stoppage determination device for a transport vehicle configured as [3] above, it is possible to detect a G-value behavior pattern specific to a transport vehicle, such as the pre-stop behavior BP2-A shown in Figures 2(a) to 2(c), and correctly determine the stopped state of the transport vehicle.

[0086] [4] A noise filter (filter processing unit 19) is provided to remove, as noise, mechanical vibration components generated on the transport vehicle and vibration components caused by road surface conditions from the acceleration value (acceleration signal Gx) in the vehicle traveling direction acquired by the acceleration sensor. The stop determination device for a transport vehicle according to any one of [1] to [3] above.

[0087] According to the stoppage determination device for a transport vehicle configured as [4] above, it becomes easy to improve the accuracy of determining the stopped state of the transport vehicle by eliminating the influence of engine vibrations and road surface irregularities that occur while the vehicle is stopped.

[0088] [5] A vehicle-specific correction database (18) is provided, which stores correction values that depend on differences in the vehicle types of the transport vehicles, for each vehicle type; At least one of the first state detection unit, the second state detection unit, and the final determination unit reflects the correction value acquired from the vehicle-specific correction database in the content of the processing. The stop determination device for a transport vehicle according to any one of [1] to [4] above.

[0089] According to the transport vehicle stop determination device configured as described above in [5], more appropriate parameters can be used taking into account the influence of differences in vehicle types such as engine vehicles and battery vehicles and differences in vehicle size, thereby improving the accuracy of determination. [Explanation of symbols]

[0090] 10 Stop judgment onboard device 11 Acceleration sensor 12 Averaging processing section 13 Stop start detection unit 14 Minus acceleration detector 15 Positive acceleration detector 16 Gx0 point detection section 17 Gx0 Behavior Monitoring Unit 18 Vehicle-specific correction database 19 Filter processing section 20 G-value gradient judgment section 21 Stop time judgment section 22 Forward / reverse detection unit 30 Forklift management device 40 Performance data management device 41 Performance Data Acquisition Department 42 Vehicle-specific performance database 43 Correction value addition processing unit Asp Stop judgment section BP1, BP1-A, BP1-B, BP1-C Pre-stop behavior BP2, BP2-A, BP2-B, BP2-C Behavior before stopping C1 Stop judgment output C2 Direction determination output DXG-A, DXG-B, DXG-C X-axis direction G value DYG-A, DYG-B, DYG-C Y-axis direction G value DZG-A, DZG-B, DZG-C Z-axis G value Gx acceleration signal Gx0 Gx reference value Gxf Filter output acceleration K1 filter coefficient K2 G-value slope threshold RST Reset signal SGs Stop start signal tss Stop start point

Claims

1. A stop determination device that determines whether a transport vehicle has stopped based on a measurement value acquired by a predetermined acceleration sensor installed on the transport vehicle, a first state detection unit that detects a first state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a negative direction compared to a predetermined reference value; a second state detection unit that detects a second state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a positive direction compared to the reference value; a final determination unit that determines whether the transport vehicle should be stopped based on the detection of the second state after the detection of the first state; A stop determination device for a transport vehicle.

2. A stop determination device that determines whether a transport vehicle has stopped based on measurements acquired by a predetermined acceleration sensor installed on the transport vehicle, a first state detection unit that detects a first state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a negative direction compared to a predetermined reference value; a second state detection unit that detects a second state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a positive direction compared to the reference value; a final determination unit that determines whether the transport vehicle should be stopped based on the detection state of the first state detection unit and the detection state of the second state detection unit; a travel direction detection unit that distinguishes between forward and backward travel of the transport vehicle, The final determination unit reflects the difference between forward and backward movement of the transport vehicle in the difference in the determination conditions. A device for determining whether a transport vehicle is stopped.

3. A stop determination device that determines whether a transport vehicle has stopped based on measurements acquired by a predetermined acceleration sensor installed on the transport vehicle, a first state detection unit that detects a first state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a negative direction compared to a predetermined reference value; a second state detection unit that detects a second state in which the acceleration value in the vehicle traveling direction acquired by the acceleration sensor changes in a positive direction compared to the reference value; a final determination unit that determines whether the transport vehicle should be stopped based on the detection state of the first state detection unit and the detection state of the second state detection unit; a downward slope detection unit that detects a slope of change of the acceleration value in the vehicle traveling direction acquired by the acceleration sensor, the slope decreasing from a positive direction relative to a predetermined reference value; A device for determining whether a transport vehicle is stopped.

4. a noise filter that removes, as noise, mechanical vibration components generated on the transport vehicle and vibration components caused by road surface conditions from the acceleration values in the vehicle traveling direction acquired by the acceleration sensor; The stop determination device for a transport vehicle according to any one of claims 1 to 3.

5. a vehicle-specific correction database that stores, for each vehicle type, a correction value that depends on the vehicle type of the transport vehicle; At least one of the first state detection unit, the second state detection unit, and the final determination unit reflects the correction value acquired from the vehicle-specific correction database in the content of the processing. The stop determination device for a transport vehicle according to any one of claims 1 to 4.

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