Mobile control device

Abstract

To achieve smooth assist operation.SOLUTION: A control device for a moving body controls an electric motor that assists running of a moving body. The control device for a moving body comprises a rolling resistance calculating part 14, a power loss calculating part 13 and an assist force calculating part 16. The rolling force calculating part 14 calculates rolling resistance on the basis of set weight set by a user. The power loss calculating part 13 calculates power loss caused until power outputted from the electric motor is transmitted to a driving wheel. The assist force calculating part 16 calculates assist force of the electric motor, on the basis of acceleration of the moving body, the set weight, the rolling resistance calculated by the rolling resistance calculating part 14, the power loss calculated by the power loss calculating part 13 and an assist rate.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device for a moving object. [Background technology]

[0002] It has been proposed to attach a drive unit to a mobile body that moves at low speed, such as a pallet truck, a hand lift truck, a hand truck, or a wheelchair, to improve the performance of the mobile body. The drive unit includes an electric motor for driving the wheels to rotate, and a control device for controlling the electric motor. The electric motor outputs an assist force to assist the human power when the mobile body is propelled by human power.

[0003] For example, the control device disclosed in Patent Document 1 calculates the mass of the moving body based on the acceleration of the moving body, and controls the assist force in accordance with the calculated mass. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4495444 Summary of the Invention [Problem to be solved by the invention]

[0005] If the assist force is controlled according to the mass calculated as described above, there is a risk that a smooth assist operation cannot be achieved due to the influence of noise and calculation errors. Therefore, an object of the present invention is to achieve a smooth assist operation. [Means for solving the problem]

[0006] A mobile object control device according to one aspect of the present invention controls an electric motor that assists the traveling of a mobile object. This mobile object control device includes a rolling resistance calculation unit, a power loss calculation unit, and an assist force calculation unit. The rolling resistance calculation unit calculates rolling resistance based on a set weight set by a user. The power loss calculation unit calculates power loss from the power output from the electric motor until it is transmitted to the drive wheels. The assist force calculation unit calculates the assist force of the electric motor based on the acceleration of the mobile object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and the assist rate.

[0007] According to this configuration, the assist force calculation unit calculates the assist force based on parameters with little calculation error without calculating the weight, thereby achieving a smooth assist operation.

[0008] Preferably, the mobile object control device further includes a driving force calculation unit that calculates the driving force applied to the mobile object based on the acceleration of the mobile object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, and the power loss calculated by the power loss calculation unit. The assist force calculation unit calculates the assist force of the electric motor based on the driving force calculated by the driving force calculation unit and the assist rate.

[0009] Preferably, the vehicle control device further includes a current control unit that calculates a current flowing through the electric motor based on the assist force.

[0010] Preferably, the power loss calculation unit calculates the shaft viscous resistance based on a vehicle speed of the moving object.

[0011] Preferably, the mobile object control device further includes an inclination angle detection unit that detects an inclination angle of a road surface on which the mobile object travels. The rolling resistance calculation unit corrects the rolling resistance based on the inclination angle detected by the inclination angle detection unit. The driving force calculation unit corrects the driving force based on the inclination angle detected by the inclination angle detection unit.

[0012] Preferably, the rolling resistance calculation unit corrects the rolling resistance when the vehicle speed of the moving object becomes equal to or greater than a first threshold value.

[0013] Preferably, the power loss calculation unit corrects the power loss when the vehicle speed of the moving object becomes equal to or greater than a second threshold value.

[0014] Preferably, the vehicle control device further includes an assist force control unit, the assist force control unit stopping the calculation of the assist force by the assist force calculation unit and setting the assist force to a preset value.

[0015] Preferably, the assist force control unit stops the calculation of the assist force by the assist force calculation unit and sets the assist force to a preset value from the start of the assist control until the moving object reaches a preset vehicle speed.

[0016] Preferably, the assist force control section stops the calculation of the assist force by the assist force calculation section until a preset time has elapsed since the start of the assist control, and sets the assist force to a preset value.

[0017] Preferably, the assist force control section sets the assist force to zero when the moving object remains stationary even after a preset time has elapsed.

[0018] Preferably, the control device for a moving object further includes an assist limiting unit that performs at least one of stopping the assist operation and applying the brakes.

[0019] Preferably, when the assist limiting unit determines that the acceleration of the moving object is equal to or greater than a third threshold, the assist limiting unit performs at least one of stopping the assisting operation and applying the brakes.

[0020] Preferably, when the assist limiting unit determines that the vehicle speed of the moving object is equal to or greater than a fourth threshold value, the assist limiting unit performs at least one of stopping the assist operation and applying the brakes.

[0021] Preferably, the assist force calculation unit increases the assist force in response to an operation by the user.

[0022] Preferably, the assist force calculation unit calculates an increase in the assist force based on the set weight and a preset tilt angle.

[0023] Preferably, the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a first correction coefficient when the vehicle speed of the moving object is less than a fifth threshold, and corrects the rolling resistance by multiplying the rolling resistance by a second correction coefficient when the vehicle speed of the moving object is equal to or greater than the fifth threshold and less than a sixth threshold. The second correction coefficient increases as the vehicle speed increases. A rate of change of the second correction coefficient is greater than a rate of change of the first correction coefficient.

[0024] Preferably, when the vehicle speed of the moving object is equal to or greater than a sixth threshold and less than a seventh threshold, the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a third correction coefficient, the third correction coefficient having a smaller rate of change than the second correction coefficient.

[0025] Preferably, when the vehicle speed of the moving object is equal to or greater than a seventh threshold and less than an eighth threshold, the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a fourth correction coefficient, the fourth correction coefficient decreasing as the vehicle speed increases.

[0026] Preferably, when the vehicle speed of the moving object is equal to or greater than an eighth threshold, the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a fifth correction coefficient, the fifth correction coefficient having a smaller rate of change than the fourth correction coefficient.

[0027] Preferably, the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a sixth correction coefficient when the vehicle speed of the moving body is less than a ninth threshold, and corrects the power loss by multiplying the axial viscous resistance by a seventh correction coefficient when the vehicle speed of the moving body is equal to or greater than the ninth threshold and less than a tenth threshold. The seventh correction coefficient increases as the vehicle speed increases. A rate of change of the seventh correction coefficient is greater than a rate of change of the sixth correction coefficient.

[0028] Preferably, when the vehicle speed of the moving object is equal to or greater than a tenth threshold and less than an eleventh threshold, the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by an eighth correction coefficient, the eighth correction coefficient having a smaller rate of change than the seventh correction coefficient.

[0029] Preferably, when the vehicle speed of the moving object is equal to or greater than an eleventh threshold and less than a twelfth threshold, the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a ninth correction coefficient, the ninth correction coefficient decreasing as the vehicle speed increases.

[0030] Preferably, when the vehicle speed of the moving object is equal to or greater than a twelfth threshold, the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a tenth correction coefficient, the tenth correction coefficient having a smaller rate of change than the ninth correction coefficient. [Effects of the Invention]

[0031] According to the present invention, a smooth assist operation can be achieved. [Brief explanation of the drawings]

[0032] [Figure 1] Side view of a pallet truck. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] 4 is a flowchart showing the operation of a control unit. [Figure 5] FIG. 10 is a block diagram of a control unit according to a modified example. [Figure 6] FIG. 10 is a block diagram of a control unit according to a modified example. [Figure 7] FIG. 10 is a block diagram of a control unit according to a modified example. [Figure 8] 4 is a graph showing the relationship between vehicle speed and rolling resistance correction coefficient. [Figure 9] 4 is a graph showing the relationship between vehicle speed and shaft viscous resistance correction coefficient. DETAILED DESCRIPTION OF THE INVENTION

[0033] A mobile body control device according to this embodiment will be described below with reference to the drawings. The mobile body control device (hereinafter also simply referred to as "control device") is configured to control an electric motor that assists the travel of the mobile body. The control device is provided on the mobile body. The mobile body travels by human power. The mobile body travels at a low speed. The mobile body is configured to transport an object. The concept of "object" includes people, etc. Examples of such mobile bodies include a pallet truck, a hand lift truck, a hand truck, and a wheelchair. In this embodiment, the mobile body is a pallet truck.

[0034] <Pallet truck> Fig. 1 is a side view of a pallet truck 200 equipped with a control device. As shown in Fig. 1, the pallet truck 200 has a pallet truck body 210 and a drive unit 20. The pallet truck body 210 has a loading platform (a pair of fork arms) 201, an operating handle 202, and a plurality of wheels 204. Note that each wheel 204 is a non-drive wheel. The drive unit 20 is attached to this pallet truck body 210.

[0035] <Drive unit> 2, the drive unit 20 includes an electric motor 21, a motor driver 22, a reducer 23, a battery 24 (see FIG. 1), drive wheels 203, and a control device 100. The drive unit 20 does not necessarily have to have drive wheels 203. In this case, the drive unit 20 drives and rotates at least one of the wheels 204 of the pallet truck 200 instead of the drive wheels 203.

[0036] When a user is manually driving the pallet truck 200, the electric motor 21 outputs an assist force for assisting the driving of the pallet truck 200. The electric motor 21 drives the drive wheels 203 to rotate.

[0037] The motor driver 22 controls the power supplied from the battery 24 to the electric motor 21. The motor driver 22 is connected to the control device 100 so as to be able to communicate with the control device 100 via wire or wirelessly. The motor driver 22 drives the electric motor 21 in response to a control signal from the control device 100.

[0038] The reducer 23 reduces the rotation speed of the electric motor 21 and transmits the rotation to the drive wheels 203. The reducer 23 is made up of, for example, a plurality of gears.

[0039] <Control device> The control device 100 includes a set weight input unit 2, a rotation speed detection unit 3, a tilt angle detection unit 4, and a control unit 10.

[0040] The set weight input unit 2 is configured to allow the user to input a set weight. For example, the set weight input unit 2 has a plurality of preset set weight options. The user can use the set weight input unit 2 to select the most suitable set weight.

[0041] The set weight input unit 2 may be configured, for example, by a rotary switch. The set weight input unit 2 is attached, for example, to the operating handle 202. The set weight input unit 2 may be configured so that an arbitrary set weight can be input by a touch panel or the like.

[0042] The set weight is the combined weight of the pallet truck 200 and the transported object, but it may also be the weight of the transported object only. In the case of the weight of the transported object only, the control unit 10 adds the weight of the pallet truck 200 to the set weight and performs various calculations.

[0043] The rotation speed detection unit 3 is configured to detect the rotation speed of the electric motor 21. The rotation speed detection unit 3 can be configured by a Hall sensor attached inside the electric motor 21, for example.

[0044] The inclination angle detection unit 4 detects the inclination angle of the road surface on which the pallet truck 200 travels. The inclination angle detection unit 4 can be configured by, for example, an inclination sensor. The inclination angle detection unit 4 may also be configured by an acceleration sensor, a gyro sensor, or the like.

[0045] The control unit 10 is configured by, for example, a computer (for example, a microcomputer) equipped with a CPU (Central Processing Unit) and a ROM (Read Only Memory). The ROM stores programs for performing various calculations. The CPU executes the programs stored in the ROM.

[0046] As shown in FIG. 3, the control unit 10 includes a vehicle speed calculation unit 11, an acceleration calculation unit 12, a power loss calculation unit 13, a rolling resistance calculation unit 14, a driving force calculation unit 15, an assist force calculation unit 16, and a current control unit 17.

[0047] The vehicle speed calculation unit 11 calculates the vehicle speed of the pallet truck 200 based on the rotation speed N of the electric motor 21 detected by the rotation speed detection unit 3, the reduction ratio i of the reducer 23, and the wheel radius R of the drive wheels 203. Specifically, the vehicle speed calculation unit 11 calculates the vehicle speed V according to the following equation (1). Note that the reduction ratio i and the wheel radius R are stored in advance in the control unit 10, but may be rewritten as appropriate.

[0048]

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[0049] The acceleration calculation unit 12 calculates the acceleration of the pallet truck 200 by differentiating (also called complete differentiation) the vehicle speed V calculated by the vehicle speed calculation unit 11. Specifically, the acceleration calculation unit 12 calculates the acceleration a according to the following equation (2). In the following equation, t represents time. The following equation is written in the time domain.

[0050]

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[0051] The acceleration calculation unit 12 may calculate the acceleration a by performing pseudo differentiation (also called inexact differentiation) of the vehicle speed V as shown in the following equation (3). Note that the following equation is written in the frequency domain.

[0052]

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[0053] The acceleration calculation unit 12 may have at least one of an upper limiter and a lower limiter. The upper limiter can prevent excessive assist operation in response to sudden acceleration. The lower limiter can prevent the assist force from being undercalculated due to noise or negative acceleration calculated when going over a bump.

[0054] The power loss calculation unit 13 calculates the power loss Fv from the power output from the electric motor 21 until it is transmitted to the drive wheels 203. The power loss calculation unit 13 calculates the power loss Fv, for example, by the following equation (4).

[0055]

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[0056] The rolling resistance calculation unit 14 calculates the rolling resistance based on the set weight M input to the set weight input unit 2. The rolling resistance calculation unit 14 also corrects the rolling resistance based on the inclination angle θ detected by the inclination angle detection unit 4. Specifically, the rolling resistance calculation unit 14 calculates the rolling resistance Fr by the following equation (5).

[0057]

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[0058] The driving force calculation unit 15 calculates the driving force applied to the pallet truck 200 based on the acceleration a calculated by the acceleration calculation unit 12, the set weight M input to the set weight input unit 2, the rolling resistance Fr calculated by the rolling resistance calculation unit 14, and the power loss Fv calculated by the power loss calculation unit 13. The driving force calculation unit 15 also corrects the driving force based on the tilt angle θ detected by the tilt angle detection unit 4. More specifically, Mgsinθ is added as shown in the following equation (6). The driving force applied to the pallet truck 200 is a combination of the human power of the user and the assist force of the electric motor 21.

[0059] Specifically, the driving force calculation unit 15 calculates the driving force F using the following equation (6).

[0060]

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[0061] The driving force calculation unit 15 may calculate the driving force F using the vehicle speed V calculated by the vehicle speed calculation unit 11 instead of the acceleration a calculated by the acceleration calculation unit 12. In detail, the driving force calculation unit 15 may calculate the driving force F by the following equation (7).

[0062]

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[0063] The assist force calculation unit 16 calculates the assist force based on the acceleration a calculated by the acceleration calculation unit 12, the set weight M input to the set weight input unit 2, the rolling resistance Fr calculated by the rolling resistance calculation unit 14, the power loss Fv calculated by the power loss calculation unit 13, and the assist rate α.

[0064] In this embodiment, the driving force calculation unit 15 calculates the driving force F based on the acceleration a, the set weight M, the rolling resistance Fr, and the power loss Fv, and the assist force calculation unit 16 calculates the assist force using the driving force F. Specifically, the assist force calculation unit 16 calculates the assist force output by the electric motor 21 based on the driving force F calculated by the driving force calculation unit 15 and the assist rate α. In more detail, the assist force calculation unit 16 calculates the assist force Fa using the following equation (8).

[0065]

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[0066] The current control unit 17 calculates the current flowing through the electric motor 21 based on the wheel radius R of the drive wheel 203, the reduction ratio i of the reducer 23, the motor torque constant Kt, and the assist force Fa calculated by the assist force calculation unit 16. The current control unit 17 outputs a control signal to the motor driver 22 so that the calculated current flows through the electric motor 21. The current control unit 17 calculates the motor current i mref Calculate.

[0067]

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[0068] The motor torque constant Kt is calculated by the following equation (10): m is a constant that associates

[0069]

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[0070] In addition, the current control unit 17 controls the motor current i mref In addition to calculating the motor current, the calculated motor current is compared with the motor current that actually flows through the electric motor 21 to perform feedback control, and then a control signal (such as a duty ratio) is output to the motor driver 22.

[0071] <Controller operation> Next, an example of processing executed by the control unit 10 will be described with reference to the flowchart of FIG.

[0072] First, the vehicle speed calculation unit 11 calculates the vehicle speed of the pallet truck 200 (step S1).

[0073] Next, the acceleration calculation unit 12 calculates the acceleration of the pallet truck 200 based on this vehicle speed (step S2). Furthermore, the power loss calculation unit 13 calculates the power loss until the assist force output by the electric motor 21 is transmitted to the drive wheels 203 based on the vehicle speed (step S3). Note that the order of the processing of step S2 and the processing of step S3 may be reversed.

[0074] The rolling resistance calculation unit 14 calculates the rolling resistance occurring between the drive wheels 203 and the road surface when the pallet truck 200 travels (step S4). Note that the processing of step S4 may be performed before any of the processing of steps S1 to S3.

[0075] Next, the driving force calculation unit 15 calculates the driving force F applied to the pallet truck 200 based on the acceleration a calculated by the acceleration calculation unit 12, the set weight M input to the set weight input unit 2, the rolling resistance Fr calculated by the rolling resistance calculation unit 14, and the power loss Fv calculated by the power loss calculation unit 13 (step S5).

[0076] Next, the assist force calculation unit 16 calculates the assist force Fa to be output by the electric motor 21 based on the driving force F calculated by the driving force calculation unit 15 and the assist rate α (step S6).

[0077] Next, the current control unit 17 calculates the current flowing through the electric motor 21 based on the wheel radius R of the drive wheel 203, the reduction ratio i of the reducer 23, the motor torque constant Kt, and the assist force Fa calculated by the assist force calculation unit 16 (step S7). Then, the current control unit 17 outputs a control signal to the motor driver 22 so that this current flows through the electric motor 21 (step S8).

[0078] As a result of the above, the electric motor 21 outputs the assist force calculated by the assist force calculation unit 16, and drives the drive wheels 203 to rotate.

[0079] [Variations] Although the embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications are possible without departing from the spirit of the present invention. In addition, the following modifications can be applied simultaneously with each other.

[0080] (a) In the above embodiment, the control device 100 includes the vehicle speed calculation unit 11, but the control device 100 does not necessarily have to include the vehicle speed calculation unit 11. For example, the control device 100 may include a vehicle speed sensor instead of the vehicle speed calculation unit 11.

[0081] (b) In the above embodiment, the control device 100 includes the acceleration calculation unit 12, but the control device 100 does not necessarily have to include the acceleration calculation unit 12. For example, the control device 100 may include an acceleration sensor instead of the acceleration calculation unit 12.

[0082] (c) In the above embodiment, the control device 100 includes the driving force calculation unit 15, but the configuration of the control device 100 is not limited to this. For example, as shown in FIG. 5, the control device 100 does not need to include the driving force calculation unit 15.

[0083] In this case, the assist force calculation unit 16 calculates the assist force based on the acceleration a calculated by the acceleration calculation unit 12, the set weight M input to the set weight input unit 2, the rolling resistance Fr calculated by the rolling resistance calculation unit 14, the power loss Fv calculated by the power loss calculation unit 13, and the assist rate α.

[0084] Specifically, the assist force calculation unit 16 calculates the assist force Fa by the following equation (11).

[0085]

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[0086] (d) In the above embodiment, the control device 100 includes the inclination angle detection unit 4, but the configuration of the control device 100 is not limited to this. For example, when the control device 100 is used on a flat surface, such as inside a factory building, the control device 100 does not need to include the inclination angle detection unit 4.

[0087] In this case, the rolling resistance calculation unit 14 does not correct the rolling resistance based on the inclination angle θ. That is, in the above embodiment, the rolling resistance calculation unit 14 corrects the rolling resistance based on the inclination angle θ, but in this modified example, the rolling resistance calculation unit 14 does not correct the rolling resistance. In this case, the rolling resistance calculation unit 14 calculates the rolling resistance by setting the inclination angle θ in the above equation (5) to zero.

[0088] Furthermore, while the driving force calculation unit 15 corrects the driving force based on the tilt angle θ in the above embodiment, in this modified example the driving force is not corrected based on the tilt angle θ. That is, the driving force calculation unit 15 calculates the driving force by setting the tilt angle θ to zero in the above equation (6).

[0089] (e) The rolling resistance calculation unit 14 may correct the rolling resistance Fr when the vehicle speed of the pallet truck 200 becomes equal to or greater than a first threshold. In detail, the rolling resistance calculation unit 14 may calculate the rolling resistance Fr by the following equation (12).

[0090]

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[0091] As described above, the rolling resistance calculation unit 14 corrects the rolling resistance Fr, thereby making it possible to absorb the influence of inertia.

[0092] (f) The power loss calculation unit 13 may correct the power loss when the vehicle speed of the pallet truck 200 becomes equal to or greater than a second threshold. In particular, the power loss calculation unit 13 may correct the axial viscous resistance. Note that the second threshold may be the same as or different from the first threshold. The power loss calculation unit 13 may calculate the power loss Fv by the following equation (13).

[0093]

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[0094] As described above, the power loss calculation unit 13 corrects the power loss Fv, thereby making it possible to absorb the influence of inertia.

[0095] (g) As shown in FIG. 6, the control device 100 may further include an assist force control unit 18. The assist force control unit 18 stops the calculation of the assist force by the assist force calculation unit 16 from the start of assist control until the pallet truck 200 reaches a preset vehicle speed. Instead, the assist force control unit 18 sets the assist force to a preset value. In this case, the current control unit 17 calculates a current so that the assist force becomes the preset value. Note that the preset value does not have to be a constant value.

[0096] The determination of whether to start assist control can be made, for example, as follows: A switch for outputting an assist force is installed on the operating handle, etc. Then, when the switch is turned on, assist control is started.

[0097] (h) In the above modification, the assist force control unit 18 controls the assist force based on the vehicle speed, but the assist force may also be controlled based on the elapsed time. Specifically, the assist force control unit 18 stops the calculation of the assist force by the assist force calculation unit 16 until a preset time has elapsed since the start of the assist control. Instead, the assist force control unit 18 sets the assist force to a preset value.

[0098] The assist force control unit 18 may set the assist force to zero when it determines that the pallet truck 200 is still stopped after a preset time has elapsed. The assist force control unit 18 may also control the assist force based on both the vehicle speed and the elapsed time.

[0099] (i) As shown in FIG. 7, the control device 100 may further include an assist limiting unit 19. The assist limiting unit 19 determines whether the acceleration of the pallet truck 200 is equal to or greater than a third threshold. If the assist limiting unit 19 determines that the acceleration is equal to or greater than the third threshold, it stops the assisting operation by the electric motor 21 until the vehicle speed of the pallet truck 200 becomes equal to or less than a preset value. Note that the assist limiting unit 19 may activate a brake instead of stopping the assisting operation. Note that the brake may be, for example, a regenerative brake or a short brake by the electric motor 21.

[0100] (j) In the above modification, the assist limiting unit 19 stops the assisting operation or activates the brakes based on the acceleration of the pallet truck 200. However, the assist limiting unit 19 may also stop the assisting operation or activate the brakes based on the vehicle speed of the pallet truck 200. That is, the assist limiting unit 19 determines whether the vehicle speed of the pallet truck 200 is equal to or greater than a fourth threshold, and if it determines that the vehicle speed is equal to or greater than the fourth threshold, at least one of stopping the assisting operation and activating the brakes is performed. Note that the assist limiting unit 19 may also stop the assisting operation or activating the brakes based on both the acceleration and vehicle speed of the pallet truck 200.

[0101] (k) The assist force calculation unit 16 may be configured to increase the assist force in response to an operation by the user. For example, the control device 100 has a boost input unit. The boost input unit can be configured, for example, by a push button. The boost input unit is attached, for example, to the operating handle 202. When the user operates (e.g., presses) the boost input unit, the assist force calculation unit 16 increases the assist force. For example, the assist force calculation unit 16 calculates the increase in the assist force based on the set weight and the preset tilt angle described above.

[0102] The assist force calculation unit 16 calculates the assist force Fa, for example, by the following equation (14) or equation (15). The assist force calculation unit 16 determines whether or not the boost input unit has been operated. If it determines that the boost input unit has not been operated, it calculates the assist force Fa by setting θ in the following equations (14) and (15) to zero. In other words, it does not increase the assist force. On the other hand, if it determines that the boost input unit has been operated, it calculates the assist force Fa by substituting a value greater than 0 for θ in the following equations (14) or (15). For example, the assist force calculation unit 16 calculates the assist force by substituting a value of 0.1 to 5° for θ in the following equations (14) and (15). In this way, the assist force calculation unit 16 increases the assist force.

[0103]

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[0104]

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[0105] In this modification, the control device 100 does not have the tilt angle detection unit 4, but may have the tilt angle detection unit 4.

[0106] (l) The rolling resistance calculation unit 14 may correct the rolling resistance using a rolling resistance correction coefficient γ. In this modification, unlike modification (e), the rolling resistance calculation unit 14 changes the rolling resistance correction coefficient γ depending on the vehicle speed.

[0107] In detail, as shown in FIG. 8, when the vehicle speed of the pallet truck 200 is less than a fifth threshold value v5, the rolling resistance calculation unit 14 corrects the rolling resistance Fr by multiplying the rolling resistance Fr calculated by the above-mentioned equation (5) by a first correction coefficient γ1. It is preferable that the first correction coefficient γ1 does not change depending on the vehicle speed and is a constant value. Note that the first correction coefficient γ1 may increase or decrease depending on the vehicle speed. Furthermore, the first correction coefficient γ1 is, for example, less than 1.

[0108] When the vehicle speed of the pallet truck 200 is equal to or greater than the fifth threshold value v5 and less than the sixth threshold value v6, the rolling resistance calculation unit 14 corrects the rolling resistance Fr by multiplying the rolling resistance Fr calculated by the above-mentioned equation (5) by the second correction coefficient γ2. The second correction coefficient γ2 increases as the vehicle speed increases. The rate of change (rate of increase) of this second correction coefficient γ2 is greater than the rate of change of the first correction coefficient γ1. Note that the second correction coefficient γ2 is, for example, equal to or less than 1.

[0109] When the vehicle speed of the pallet truck 200 is equal to or greater than the sixth threshold value v6 and less than the seventh threshold value v7, the rolling resistance calculation unit 14 corrects the rolling resistance Fr by multiplying the rolling resistance Fr calculated by the above-mentioned equation (5) by the third correction coefficient γ3. It is preferable that the third correction coefficient γ3 is constant and does not change depending on the vehicle speed. The third correction coefficient γ3 is greater than the first correction coefficient γ1. The third correction coefficient γ3 can also be set to the same value as the maximum value of the second correction coefficient γ2. The third correction coefficient γ3 can be set to 1, for example. The third correction coefficient γ3 may increase or decrease depending on the vehicle speed. In this case, the rate of change of the third correction coefficient γ3 is smaller than the rate of change of the second correction coefficient γ2.

[0110] When the vehicle speed of the pallet truck 200 is equal to or greater than the seventh threshold value v7 and less than the eighth threshold value v8, the rolling resistance calculation unit 14 corrects the rolling resistance Fr by multiplying the rolling resistance Fr calculated by the above-mentioned equation (5) by a fourth correction coefficient γ4. The fourth correction coefficient γ4 decreases as the vehicle speed increases. The rate of change (rate of decrease) of this fourth correction coefficient γ4 is greater than the rate of change of the third correction coefficient γ3. The fourth correction coefficient γ4 is, for example, equal to or less than 1.

[0111] When the vehicle speed of the pallet truck 200 is equal to or greater than the eighth threshold value v8, the rolling resistance calculation unit 14 corrects the rolling resistance Fr by multiplying the rolling resistance Fr calculated by the above-described formula (5) by the fifth correction coefficient γ5. It is preferable that the fifth correction coefficient γ5 is constant and does not change depending on the vehicle speed. The fifth correction coefficient γ5 is smaller than the third correction coefficient γ3. The fifth correction coefficient γ5 may be equal to the first correction coefficient γ1, or may be greater or smaller than the first correction coefficient γ1. The fifth correction coefficient γ5 may be set to the same value as the minimum value of the fourth correction coefficient γ4. The fifth correction coefficient γ5 may be set to, for example, less than 1. The fifth correction coefficient γ5 may increase or decrease depending on the vehicle speed. In this case, the rate of change of the fifth correction coefficient γ5 is smaller than the rate of change of the fourth correction coefficient γ4.

[0112] (m) The power loss calculation unit 13 may correct the axial viscous resistance using an axial viscous resistance correction coefficient β. In this modification, unlike modification (f), the power loss calculation unit 13 changes the axial viscous resistance correction coefficient β in accordance with the vehicle speed.

[0113] Specifically, as shown in FIG. 9, when the vehicle speed of the pallet truck 200 is less than a ninth threshold value v9, the power loss calculation unit 13 corrects the power loss by multiplying the axial viscous resistance kV in the above-mentioned equation (4) by a sixth correction coefficient β1. It is preferable that the sixth correction coefficient β1 does not change depending on the vehicle speed and is a constant value. Note that the sixth correction coefficient β1 may increase or decrease depending on the vehicle speed. Furthermore, the sixth correction coefficient β1 is, for example, less than 1.

[0114] When the vehicle speed of the pallet truck 200 is equal to or greater than the ninth threshold v9 and less than the tenth threshold v10, the power loss calculation unit 13 corrects the power loss by multiplying the axial viscous resistance kV in the above-mentioned equation (4) by a seventh correction coefficient β2. The seventh correction coefficient β2 increases as the vehicle speed increases. The rate of change (rate of increase) of this seventh correction coefficient β2 is greater than the rate of change of the sixth correction coefficient β1. The seventh correction coefficient β2 is, for example, equal to or less than 1.

[0115] When the vehicle speed of the pallet truck 200 is equal to or greater than the tenth threshold value v10 and less than the eleventh threshold value v11, the power loss calculation unit 13 corrects the power loss by multiplying the axial viscous resistance kV in the above-mentioned equation (4) by the eighth correction coefficient β3. It is preferable that the eighth correction coefficient β3 is constant and does not change depending on the vehicle speed. The eighth correction coefficient β3 is larger than the sixth correction coefficient β1. The eighth correction coefficient β3 can also be set to the same value as the maximum value of the seventh correction coefficient β2. The eighth correction coefficient β3 can be set to 1, for example. The eighth correction coefficient β3 may increase or decrease depending on the vehicle speed. In this case, the rate of change of the eighth correction coefficient β3 is smaller than the rate of change of the seventh correction coefficient β2.

[0116] When the vehicle speed of the pallet truck 200 is equal to or greater than an eleventh threshold value v11 and less than a twelfth threshold value v12, the power loss calculation unit 13 corrects the power loss by multiplying the axial viscous resistance kV in the above-mentioned equation (4) by a ninth correction coefficient β4. The ninth correction coefficient β4 decreases as the vehicle speed increases. The rate of change (rate of decrease) of this ninth correction coefficient β4 is greater than the rate of change of the eighth correction coefficient β3. The ninth correction coefficient β4 is, for example, equal to or less than 1.

[0117] When the vehicle speed of the pallet truck 200 is equal to or greater than the twelfth threshold value v12, the power loss calculation unit 13 corrects the power loss by multiplying the axial viscous resistance kV in the above-described equation (4) by the tenth correction coefficient β5. It is preferable that the tenth correction coefficient β5 is constant and does not change depending on the vehicle speed. The tenth correction coefficient β5 is smaller than the eighth correction coefficient β3. The tenth correction coefficient β5 may be equal to the sixth correction coefficient β1, or may be greater or smaller than the sixth correction coefficient β1. The tenth correction coefficient β5 may be set to the same value as the minimum value of the ninth correction coefficient β4. The tenth correction coefficient β5 may be set to, for example, less than 1. The tenth correction coefficient β5 may increase or decrease depending on the vehicle speed. In this case, the rate of change of the tenth correction coefficient β5 is smaller than the rate of change of the ninth correction coefficient β4.

[0118] When this modification (m) is applied simultaneously with the modification (l), the ninth to twelfth thresholds v9 to v12 are respectively 5 ~8th threshold v 5May be the same as ~v8. [Explanation of symbols]

[0119] 4: Tilt angle detector 13: Power loss calculation section 14: Rolling resistance calculation section 15: Driving force calculation unit 16: Assist force calculation unit 17: Current control section 18: Assist force control section 19: Assistance limit section 21: Electric motor 22: Motor driver 100: Control device 200: Pallet truck 203: Drive wheel

Claims

1. A control device for a moving body that controls an electric motor that assists the running of the moving body, a rolling resistance calculation unit that calculates the rolling resistance based on a set weight set by a user; a power loss calculation unit that calculates a power loss from the power output from the electric motor to the drive wheels; an assist force calculation unit that calculates an assist force of the electric motor based on the acceleration of the moving object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and an assist rate; Equipped with the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a first correction coefficient when the vehicle speed of the moving body is less than a fifth threshold, and corrects the rolling resistance by multiplying the rolling resistance by a second correction coefficient that increases as the vehicle speed increases when the vehicle speed of the moving body is equal to or greater than the fifth threshold and less than a sixth threshold; The rate of change of the second correction coefficient is greater than the rate of change of the first correction coefficient. Control device for mobile objects.

2. a driving force calculation unit that calculates a driving force applied to the moving body based on the acceleration of the moving body, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, and the power loss calculated by the power loss calculation unit, the assist force calculation unit calculates an assist force of the electric motor based on the driving force calculated by the driving force calculation unit and the assist rate. The control device for a moving body according to claim 1 .

3. a current control unit that calculates a current flowing through the electric motor based on the assist force; The control device for a moving body according to claim 1 or 2.

4. the power loss calculation unit calculates the shaft viscous resistance based on the vehicle speed of the moving body; The control device for a moving body according to any one of claims 1 to 3.

5. further comprising an inclination angle detection unit that detects an inclination angle of a road surface on which the moving body is traveling, the rolling resistance calculation unit corrects the rolling resistance based on the inclination angle detected by the inclination angle detection unit; the driving force calculation unit corrects the driving force based on the tilt angle detected by the tilt angle detection unit. The control device for a moving body according to claim 2 .

6. The rolling resistance calculation unit corrects the rolling resistance when the vehicle speed of the moving object becomes equal to or greater than a first threshold value. The control device for a moving body according to any one of claims 1 to 5.

7. The power loss calculation unit corrects the power loss when the vehicle speed of the moving object becomes equal to or greater than a second threshold value. The control device for a moving body according to any one of claims 1 to 6.

8. an assist force control unit that stops the calculation of the assist force by the assist force calculation unit and sets the assist force to a preset value; The control device for a moving body according to any one of claims 1 to 7.

9. the assist force control unit stops the calculation of the assist force by the assist force calculation unit from the start of the assist control until the moving body reaches a predetermined vehicle speed, and sets the assist force to a predetermined value. The control device for a moving body according to claim 8.

10. the assist force control unit stops the calculation of the assist force by the assist force calculation unit until a preset time has elapsed since the start of the assist control, and sets the assist force to a preset value. The control device for a moving body according to claim 8 or 9.

11. the assist force control unit sets the assist force to zero when the moving object remains stationary even after a preset time has elapsed. The control device for a moving body according to any one of claims 8 to 10.

12. Further provided is an assist limiting unit that performs at least one of stopping the assist operation and applying the brakes. The control device for a moving body according to any one of claims 1 to 11.

13. the assist limiting unit performs at least one of stopping an assist operation and applying a brake when determining that the acceleration of the moving object is equal to or greater than a third threshold value. The control device for a moving body according to claim 12.

14. the assist limiting unit performs at least one of stopping an assist operation and applying a brake when determining that the vehicle speed of the moving object is equal to or greater than a fourth threshold value. The control device for a moving body according to claim 12 or 13.

15. the assist force calculation unit increases the assist force in response to an operation by a user. The control device for a moving body according to any one of claims 1 to 14.

16. the assist force calculation unit calculates an increase in the assist force based on the set weight and a preset tilt angle. The mobile object control device according to claim 15.

17. the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a third correction coefficient having a smaller rate of change than the second correction coefficient when the vehicle speed of the moving body is equal to or greater than the sixth threshold and less than the seventh threshold. The control device for a moving body according to any one of claims 1 to 16.

18. the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a fourth correction coefficient that decreases as the vehicle speed increases, when the vehicle speed of the moving object is equal to or greater than the seventh threshold and less than the eighth threshold. The control device for a moving body according to claim 17.

19. the rolling resistance calculation unit corrects the rolling resistance by multiplying the rolling resistance by a fifth correction coefficient, the fifth correction coefficient having a smaller change rate than the fourth correction coefficient, when the vehicle speed of the moving body is equal to or higher than the eighth threshold value. The control device for a moving body according to claim 18.

20. the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a sixth correction coefficient when the vehicle speed of the moving body is less than a ninth threshold, and corrects the power loss by multiplying the axial viscous resistance by a seventh correction coefficient that increases as the vehicle speed increases when the vehicle speed of the moving body is equal to or greater than the ninth threshold and less than a tenth threshold; The rate of change of the seventh correction coefficient is greater than the rate of change of the sixth correction coefficient. The control device for a moving body according to any one of claims 1 to 19.

21. the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by an eighth correction coefficient, the eighth correction coefficient having a smaller rate of change than the seventh correction coefficient, when the vehicle speed of the moving body is equal to or greater than the tenth threshold and less than the eleventh threshold. The control device for a moving body according to claim 20.

22. the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a ninth correction coefficient that decreases as the vehicle speed increases, when the vehicle speed of the moving body is equal to or greater than the eleventh threshold and less than the twelfth threshold. The control device for a moving body according to claim 21.

23. the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a tenth correction coefficient having a smaller change rate than the ninth correction coefficient when the vehicle speed of the moving body is equal to or greater than the twelfth threshold value. The control device for a moving body according to claim 22.

24. A control device for a moving body that controls an electric motor that assists the running of the moving body, a rolling resistance calculation unit that calculates the rolling resistance based on a set weight set by a user; a power loss calculation unit that calculates a power loss from the power output from the electric motor to the drive wheels; an assist force calculation unit that calculates an assist force of the electric motor based on the acceleration of the moving object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and an assist rate; Equipped with a driving force calculation unit that calculates a driving force applied to the moving body based on the acceleration of the moving body, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, and the power loss calculated by the power loss calculation unit, the assist force calculation unit calculates an assist force of the electric motor based on the driving force calculated by the driving force calculation unit and the assist rate. Control device for mobile objects.

25. A control device for a moving body that controls an electric motor that assists the running of the moving body, a rolling resistance calculation unit that calculates the rolling resistance based on a set weight set by a user; a power loss calculation unit that calculates a power loss from the power output from the electric motor to the drive wheels; an assist force calculation unit that calculates an assist force of the electric motor based on the acceleration of the moving object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and an assist rate; an assist force control unit that stops the calculation of the assist force by the assist force calculation unit and sets the assist force to a preset value; Equipped with the assist force control unit stops the calculation of the assist force by the assist force calculation unit from the start of the assist control until the moving body reaches a predetermined vehicle speed, and sets the assist force to a predetermined value. Control device for mobile objects.

26. A control device for a moving body that controls an electric motor that assists the running of the moving body, a rolling resistance calculation unit that calculates the rolling resistance based on a set weight set by a user; a power loss calculation unit that calculates a power loss from the power output from the electric motor to the drive wheels; an assist force calculation unit that calculates an assist force of the electric motor based on the acceleration of the moving object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and an assist rate; an assist force control unit that stops the calculation of the assist force by the assist force calculation unit and sets the assist force to a preset value; Equipped with the assist force control unit stops the calculation of the assist force by the assist force calculation unit until a preset time has elapsed since the start of the assist control, and sets the assist force to a preset value. Control device for mobile objects.

27. ​​A control device for a moving body that controls an electric motor that assists the running of the moving body, a rolling resistance calculation unit that calculates the rolling resistance based on a set weight set by a user; a power loss calculation unit that calculates a power loss from the power output from the electric motor to the drive wheels; an assist force calculation unit that calculates an assist force of the electric motor based on the acceleration of the moving object, the set weight, the rolling resistance calculated by the rolling resistance calculation unit, the power loss calculated by the power loss calculation unit, and an assist rate; Equipped with the power loss calculation unit corrects the power loss by multiplying the axial viscous resistance by a sixth correction coefficient when the vehicle speed of the moving body is less than a ninth threshold, and corrects the power loss by multiplying the axial viscous resistance by a seventh correction coefficient that increases as the vehicle speed increases when the vehicle speed of the moving body is equal to or greater than the ninth threshold and less than a tenth threshold; The rate of change of the seventh correction coefficient is greater than the rate of change of the sixth correction coefficient. Control device for mobile objects.

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