Control device for conveyance assistance device and control method for conveyance assistance device

Abstract

The present invention provides a control device for a conveyance assistance device and a control method for a conveyance assistance device capable of further improving operability. The control device for a conveyance assistance device comprises: an operation amount detection unit 30 that detects an operation amount 80 input to a conveyance assistance device 100; an acceleration / deceleration determination unit 32 that determines whether the movement speed of the conveyance assistance device 100 is in acceleration or deceleration on the basis of an operation amount detection value 81 detected by the operation amount detection unit 30; and a command value calculation unit 31 that calculates a command value 82 of the conveyance assistance device 100 so as to exhibit different response characteristics at acceleration and deceleration with respect to the operation amount detection value 81 on the basis of the operation amount detection value 81 and the determination result of the acceleration / deceleration determination unit 32. The control device further comprises: a main control unit 21 that outputs a control command value 83 for a drive wheel 10 included in the conveyance assistance device 100, the control command value 83 corresponding to the command value 82; and a drive control unit 22 that controls the drive wheel 10 on the basis of the control command value 83 output from the main control unit 21.

Description

Control device for transport auxiliary device and control method for transport auxiliary device

[0001] The present invention relates to a control device for a transport auxiliary device and a control method for a transport auxiliary device.

[0002] BACKGROUND ART There are known traveling assist devices that assist the traveling of traveling implements, such as carts with swivel wheels, transport carts, mobile beds, stretchers, etc., which carry an object to be transported and are manually pushed by an operator to travel on a floor surface.

[0003] For example, Patent Documents 1 and 2 disclose a bed transport device that is attached to a bed and can be operated by a remote control.

[0004] JP2018-183530A JP10-146364A

[0005] Fumitake Fujii, Kenzo Wada, "Research into the Realization of a Rider-Friendly Electric Wheelchair," Transactions of the Japan Society of Mechanical Engineers (Series C), 2000, Vol. 66, No. 645, pp. 1645-1651

[0006] It is desirable for a transport assistance device to be easy for an operator to use. Ease of use for an operator means, for example, that the responsiveness to operational inputs is appropriate for the operator (feels natural). Furthermore, when the traveling device is a mobile bed, stretcher, or other traveling device intended to transport a person, it is desirable that the traveling device not cause discomfort or anxiety to the person being transported while traveling. Even when the traveling device is a dolly, transport cart, or other object intended to transport a non-personal object, such as a container of a liquid medicine or beverage, or precision equipment, it is desirable that the object not be subjected to sudden acceleration or impact.

[0007] However, Patent Documents 1 and 2 do not disclose how the transport assist device responds to the amount of operation input from the remote control.

[0008] Non-Patent Document 1 defines the ideal operability desired by the rider, who is the operator of the electric wheelchair, i.e., the responsiveness of the movement speed that the operator desires in relation to the amount of joystick operation, as the "ideal operation impedance," and points out that if the ideal operation impedance differs significantly from the movement speed that is actually output from the device, the discomfort of having to repeatedly operate the joystick to achieve the desired behavior and the fear caused by acceleration that is different from what was expected can become stressful factors.

[0009] It is desirable to further improve the operability not only of electric wheelchairs but also of various transport assistance devices.

[0010] The present invention has been made in view of the above, and has an object to provide a control device for a transport auxiliary device and a control method for a transport auxiliary device that can further improve operability.

[0011] A control device for a transport auxiliary device according to one aspect of the present invention comprises an operation amount detection unit that detects an operation amount input to the transport auxiliary device, an acceleration / deceleration judgment unit that judges whether the movement speed of the transport auxiliary device is accelerating or decelerating based on the operation amount detection value detected by the operation amount detection unit, and a command value calculation unit that calculates a command value for the transport auxiliary device based on the operation amount detection value and the judgment result of the acceleration / deceleration judgment unit so that the response characteristics to the operation amount detection value differ during acceleration and deceleration, and also comprises a main control unit that outputs a control command value for drive wheels of the transport auxiliary device corresponding to the command value, and a drive control unit that controls the drive wheels based on the control command value output from the main control unit.

[0012] This allows the transport assist device's response characteristics to the detected operation amount to be different when accelerating and decelerating. Specifically, the inventors of the present application found that even when an external force is applied to the traveling device (e.g., when examining step response), the acceleration time required for the traveling device to reach a certain speed differs from the deceleration time required for the traveling device to stop after the application of the external force is stopped due to factors such as Coulomb friction between the traveling device's driven wheels and the floor surface, resulting in a difference in the response characteristics during acceleration and deceleration. Furthermore, the inventors found that, from the perspective of avoiding collisions with obstacles such as people or walls, rapid deceleration (rather than acceleration) is sometimes desirable when traveling using the transport assist device. Based on these findings, drive control that provides separate response characteristics during acceleration and deceleration can be used to achieve control of the transport assist device that further improves operability for the operator.

[0013] In a control device for a transport assist device according to one aspect of the present invention, the command value calculation unit switches an operation model that expresses the response of the movement speed of the transport assist device to the operation amount detection value based on the judgment result of the acceleration / deceleration judgment unit.

[0014] By switching the operation model between acceleration and deceleration, the response characteristics during acceleration and deceleration can be made closer to the response characteristics of separate ideal operation models. Furthermore, compared to realizing different response characteristics during acceleration and deceleration with a single operation model, it is easier to construct the operation model during acceleration and deceleration.

[0015] In a control device for a transport assistance device according to one aspect of the present invention, the command value calculation unit outputs the command value for the speed of the transport assistance device, and the drive control unit performs angular velocity control for the drive wheels based on the control command value for the angular velocity of the drive wheels corresponding to the command value for the speed.

[0016] According to this, the speed of the transport auxiliary device is controlled as a control amount, so that the speed response characteristics of the traveling implement caused by the transport auxiliary device can be made closer to ideal response characteristics, which can further improve operability.

[0017] In a control device for a transport auxiliary device according to one aspect of the present invention, the command value calculation unit calculates the command value based on the current value of the state of the transport auxiliary device in addition to the operation amount detection value and the judgment result of the acceleration / deceleration judgment unit.

[0018] Here, the operation of the transport assist device may experience a response delay to a command value due to the mechanical characteristics of the traveling implement and the mechanical and electrical characteristics of the transport assist device. Therefore, by calculating the command value based on the current value of the state of the transport assist device, it is possible to improve the ability of the transport assist device to follow the ideal response characteristics even when the above-mentioned response delay factors exist.

[0019] In a control device for a transport auxiliary device according to one aspect of the present invention, the current value of the state of the transport auxiliary device is the current value of the movement speed of the transport auxiliary device, and the command value calculation unit calculates the command value for the speed of the transport auxiliary device based on the detected operation amount value and the current value of the movement speed.

[0020] This improves the speed control of the transport assist device to track the ideal speed response characteristics based on the current value of the moving speed, thereby preventing the operator from feeling that the behavior of the transport assist device is sluggish (slower than expected).

[0021] In a control device for a transport assistance device according to one aspect of the present invention, the command value calculation unit calculates the command value according to the magnitude of the change in the operation amount detection value based on the current value of the operation amount detection value and the change in the operation amount detection value.

[0022] This means that, for example, when the change in the detected operating amount value is large, i.e., when the operator wants to accelerate significantly, even if there is a response delay to the command value, the ability of the transport assistance device to follow the ideal response characteristics for the operator can be improved by drive control according to the change in the detected operating amount value.

[0023] A control method for a transport auxiliary device according to one aspect of the present invention includes the steps of: detecting an operation amount input to the transport auxiliary device; determining whether the movement speed of the transport auxiliary device is accelerating or decelerating based on the detected operation amount detection value; calculating a command value for the transport auxiliary device based on the operation amount detection value and the determination result of acceleration or deceleration so that the response characteristics to the operation amount detection value differ during acceleration and deceleration; and controlling drive wheels of the transport auxiliary device based on a control command value corresponding to the command value.

[0024] This allows the response characteristics of the transport assist device to the detected operation amount to be different when the transport assist device accelerates and decelerates. That is, even when an external force is applied to the traveling device to move it (e.g., when examining the step response), differences occur between the acceleration time and the deceleration time, and the response characteristics are not symmetrical during acceleration and deceleration. Furthermore, from the perspective of avoiding collisions with obstacles while traveling using the transport assist device, quick deceleration may be desirable. Therefore, by performing drive control that provides separate response characteristics during acceleration and deceleration, control of the transport assist device can be realized that further improves operability for the operator.

[0025] In one aspect of the present invention, in the control method for a transport assistance device, in the step of calculating the command value, an operation model that expresses the response of the movement speed of the transport assistance device to the operation amount detection value is switched based on the result of the acceleration or deceleration determination.

[0026] By switching the operation model between acceleration and deceleration, the response characteristics during acceleration and deceleration can be made closer to the response characteristics of separate ideal operation models. Furthermore, compared to realizing acceleration and deceleration with a single operation model, it is easier to construct the operation model during acceleration and deceleration.

[0027] In one aspect of the present invention, a control method for a transport auxiliary device calculates a command value for the speed of the transport auxiliary device based on the detected operation amount value in the step of calculating the command value, and controls the angular velocity of the drive wheels based on a control command value for the angular velocity of the drive wheels that corresponds to the calculated command value for the speed in the step of controlling the drive wheels.

[0028] According to this, the speed of the transport auxiliary device is controlled as a control amount, so that the speed response characteristics of the traveling implement caused by the transport auxiliary device can be made closer to ideal response characteristics, which can further improve operability.

[0029] According to the present invention, it is possible to provide a control device for a transport auxiliary device and a control method for a transport auxiliary device that can further improve operability.

[0030] FIG. 1 is a perspective view showing a transportation assist device and a traveling tool. FIG. 2 is an explanatory diagram showing a schematic configuration of the transportation assist device. FIG. 3 is a block diagram showing a schematic configuration of a control device of the transportation assist device according to the first embodiment. FIG. 4 is a block diagram showing an example configuration of a control device that controls the speed of the transportation assist device. FIG. 5 is an explanatory diagram for explaining the calculation processing of a command value calculation unit. FIG. 6 is a flowchart showing the operation of the control device of the transportation assist device according to the first embodiment. FIG. 7 is a graph showing an example relationship between the movement speed of the traveling tool and time. FIG. 8 is a graph showing a first example operation of the transportation assist device according to the first embodiment. FIG. 9 is a graph showing a second example operation of the transportation assist device according to the first embodiment. FIG. 10 is a block diagram showing an example configuration of a control device of the transportation assist device according to the second embodiment. FIG. 11 is a diagram showing a first example of a command value calculation unit according to the second embodiment. FIG. 12 is a graph showing an example calculation of a correction value in the correction calculation unit. FIG. 13 is a diagram showing a second example of a command value calculation unit according to the second embodiment. FIG. 14 is a graph showing an example calculation of a calculation parameter in the parameter calculation unit. FIG. 15 is a block diagram showing an example of the configuration of a control device of a transport assist device according to the third embodiment.

[0031] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the components described below can be combined as appropriate.

[0032] First Embodiment First, a description will be given of the configuration of a transport assist device 100. Fig. 1 is a perspective view showing the transport assist device 100 and a traveling device 110.

[0033] The transport assistance device 100 is connected to the traveling tool 110 and assists the traveling of the traveling tool 110 (transportation of an object by the traveling tool 110). The traveling tool 110 has wheels 111 and travels on a floor surface with an object to be transported on board. The wheels 111 are driven wheels. In other words, the traveling tool 110 does not have a self-propelled function (drive source) and travels by external force. Such traveling tools 110 are, for example, dollies, transport carts, mobile beds, stretchers, etc. The object to be transported is not particularly limited and may be a living being such as a person or an animal, or various objects such as a container of a medicinal solution or a beverage, or precision equipment. FIG. 1 shows an example in which the traveling tool 110 is a dolly. In this example, the traveling tool 110 moves when an operator applies external force to the handle 112.

[0034] The transportation assistance device 100 is mechanically connected (coupled) to the traveling tool 110 by a connecting portion 120. The transportation assistance device 100 applies a propulsive force to the traveling tool 110 via the connecting portion 120. In the example of FIG. 1 , the connecting portion 120 includes a connecting portion main body 121 provided on the transportation assistance device 100 and an attachment member 122 provided on the underside of the traveling tool 110. When the transportation assistance device 100 is positioned so as to be under the traveling tool 110, the connecting portion main body 121 engages with the attachment member 122, thereby connecting the transportation assistance device 100 to the traveling tool 110. In the example of FIG. 1 , the connecting portion main body 121 operates to be switchable between engagement and disengagement with the attachment member 122. Therefore, the transportation assistance device 100 can be freely connected to and disconnected from the traveling tool 110. Note that the form of mechanical connection between the transportation assistance device 100 and the traveling tool 110 is not particularly limited. The transportation assist device 100 can be connected to the traveling tool 110 without the attachment member 122 on the traveling tool 110. The transportation assist device 100 is not limited to being disposed on the underside of the traveling tool 110, and may tow the traveling tool 110 from a position in front of the traveling tool 110 away from the traveling tool 110, or may push the traveling tool 110 from the rear side of the traveling tool 110 to propel it.

[0035] 2 is an explanatory diagram showing a schematic configuration of the transportation assist device 100. The transportation assist device 100 includes drive wheels 10 and a control device 20 that controls the drive wheels 10. The control device 20 and each drive wheel 10 are assembled to a housing 101.

[0036] The transportation assistance device 100 can include one or more drive wheels 10, and in the example of Fig. 2 includes a plurality of drive wheels 10. The drive wheels 10 are wheels that are rotationally driven by a drive source (motor 11).

[0037] The drive wheels 10 may be wheels capable of only forward and backward movement, or wheels capable of omnidirectional movement (such as omni-wheels or Mecanum wheels). The transport assistance device 100 includes a corresponding motor 11 and angle sensor 12 for each drive wheel 10. The motor 11 drives the drive wheels 10 to rotate. The transport assistance device 100 uses the motor 11 to generate propulsive force for propelling the traveling implement 110. The type of motor 11 is not particularly limited. For example, the motor 11 may be a brushless direct-current (BLDC) motor. The angle sensor 12 detects the rotation angle of the drive wheels 10. The type (detection method) of the angle sensor 12 is not particularly limited. For example, the angle sensor 12 may be a position detector such as a rotary encoder or a hall sensor. In addition to the drive wheels 10, the transport assistance device 100 may also include a driven wheel (not shown) that is not driven by the motor 11.

[0038] The control device 20 includes a main control unit 21 and a drive control unit 22. One main control unit 21 is provided, and a drive control unit 22 is provided for each drive wheel 10 of the transport assist device 100. The main control unit 21 and each drive control unit 22 are connected by a communication line.

[0039] The main control unit 21 controls the entire transport assist device 100 by outputting control command values ​​83 (see FIG. 3 ) to each drive control unit 22. The main control unit 21 is realized by a processing circuit such as a system LSI (Large Scale Integration) or a processor such as a CPU (Central Processing Unit) that executes a program stored in a memory or the like.

[0040] Each drive control unit 22 controls the drive of the corresponding drive wheel 10 under the control of the main control unit 21. Each drive control unit 22 is connected to the motor 11 and angle sensor 12 of the corresponding drive wheel 10 via a power line or the like. The angle sensor 12 outputs the current value of the angle of the corresponding drive wheel 10.

[0041] The transport assistance device 100 also includes an operating device 102. The transport assistance device 100 can be operated by the operating device 102 via the control device 20. As shown in FIG. 1 , the operating device 102 and the control device 20 are connected by wired or wireless communication means so that signals can be exchanged between them. The operating device 102 is an HMI (Human Machine Interface) having one or more input units 103, and can be, for example, an input device such as a mechanical switch or a joystick. The operating device 102 may also be a user interface realized by a touch panel display. The operating device 102 outputs an operation amount 80 given by an operator.

[0042] 3 is a block diagram showing an example of the configuration of the control device 20 of the transport assist device 100 according to the first embodiment. Note that in Fig. 3, only one set of a drive control unit 22 and a motor 11 is shown.

[0043] In the example of FIG. 3, the main control unit 21 includes an operation amount detection unit 30 , a command value calculation unit 31 , an acceleration / deceleration determination unit 32 , and a command value conversion unit 33 .

[0044] The operation amount detection unit 30 detects an operation amount 80 input from the operation device 102 to the transport assist device 100. The operation amount detection unit 30 outputs the detected operation amount 80 as an operation amount detection value 81 at a predetermined sampling period.

[0045] The acceleration / deceleration determination unit 32 determines whether the movement speed of the transport assist device 100 is accelerating or decelerating based on the operation amount detection value 81 detected by the operation amount detection unit 30. The acceleration / deceleration determination unit 32 determines whether the input from the operation device 102 indicates acceleration or deceleration based on, for example, a comparison between the latest operation amount detection value 81 and the immediately previous operation amount detection value 81 (one sample before). The acceleration / deceleration determination unit 32 outputs the determination result (acceleration or deceleration) to the command value calculation unit 31.

[0046] The command value calculation unit 31 calculates a command value 82 for the transport assist device 100 based on the operation amount detection value 81 and the determination result of the acceleration / deceleration determination unit 32. The command value calculation unit 31 calculates and outputs the command value 82 that represents the overall movement control of the transport assist device 100.

[0047] The command value converter 33 converts the calculation result (command value 82) of the command value calculator 31 into a command value for each drive wheel 10. In other words, the command value converter 33 converts the overall command value 82 for the transportation assist device 100 into control command values ​​83 for each individual drive control unit 22. As a result, the main control unit 21 outputs the control command value 83 corresponding to the command value 82 of the command value calculator 31 to each corresponding drive control unit 22.

[0048] The drive control unit 22 controls the drive wheels 10 of the transportation assist device 100 based on the control command value 83 output from the main control unit 21. That is, the drive control unit 22 calculates and outputs a drive current 90 for the motor 11 of the corresponding drive wheel 10 based on the control command value 83. As a result, the motor 11 of each drive wheel 10 drives and rotates the corresponding drive wheel 10 with a drive force according to the supplied drive current 90.

[0049] There are various control methods by the control device 20, and no particular limitation is imposed on them. As an example, Fig. 4 is a block diagram showing an example of the configuration of the control device 20 that controls the speed of the transport assist device 100.

[0050] In the configuration example shown in FIG. 4 , the command value calculation unit 31 outputs the calculation result (command value 82) as a speed command value. The command value calculation unit 31 calculates the command value 82 for the movement speed of the transport assistance device 100 based on an operation model (operation impedance models 40a, 40b, see FIG. 5 ) described below. Note that the "movement speed of the transport assistance device 100" refers to the movement speed at the connection point (connection portion 120) between the traveling tool 110 and the transport assistance device 100 or at any point relative to the connection point. The movement speed of the transport assistance device 100 may also be referred to as the speed of the transport assistance device 100, but unless otherwise specified, these terms have the same meaning. Here, the command value 82 is a command value expressed in a Cartesian coordinate system, which is the speed of the transport assistance device 100.

[0051] The command value converter 33 converts the command value 82 expressed in the Cartesian coordinate system into a control command value 83 expressed in the wheel coordinate system. For example, the command value converter 33 calculates a control command value 83 for the angular velocity of each driving wheel 10 by multiplying the speed command value 82 expressed in the Cartesian coordinate system by the inverse matrix of the Jacobian matrix. In FIG. 4, J represents the Jacobian matrix, and J －１ is the inverse of the Jacobian matrix.

[0052] 4 , the drive control unit 22 performs angular velocity control for the drive wheels 10 based on a control command value 83 for the angular velocity of the drive wheels 10 corresponding to a speed command value 82. That is, the drive control unit 22 calculates a command value (drive current 90) for the motor 11 provided in the corresponding drive wheel 10 based on the angular velocity control command value 83 calculated by the main control unit 21 and the current value of the angle of each drive wheel 10. The drive control unit 22 includes a speed control unit 50 having a subtractor 50a and a PI control unit 50b, a speed conversion unit 51, and a power conversion unit 52.

[0053] The speed conversion unit 51 converts the current angle value (current angle value 85) obtained from the angle sensor 12 into a current angular velocity value (current angular velocity value 86). The speed control unit 50 subtracts the current angular velocity value 86 obtained by the speed conversion unit 51 from the angular velocity control command value 83 using a subtractor 50a to obtain a calculation result of the angular velocity deviation. The speed control unit 50 performs proportional-integral (PI) control using a PI control unit 50b based on the subtraction result (angular velocity deviation) obtained by the subtractor 50a, thereby obtaining a command value (drive current command value) 84 for the motor 11. The power conversion unit 52 outputs a drive current 90 to the motor 11 using, for example, PWM (Pulse Width Modulation) control based on the command value 84 obtained by the PI control unit 50b, to drive the motor. Although not specifically shown, the power conversion unit 52 also has a feedback loop of a current control system.

[0054] 5 is an explanatory diagram for explaining the calculation process of the command value calculation unit 31. In the first embodiment, the command value calculation unit 31 calculates a command value 82 for the drive wheels 10 of the transportation assist device 100 based on the operation amount detection value 81 and the determination result of the acceleration / deceleration determination unit 32 so as to have different response characteristics during acceleration and deceleration.

[0055] Specifically, the command value calculation unit 31 has multiple operation models (two in this example), including an operation impedance model 40a when the transport assistance device 100 is accelerating and an operation impedance model 40b when the transport assistance device 100 is decelerating. The operation impedance models 40a and 40b are models that express the response of the movement speed of the transport assistance device 100 to the operation amount detection value 81. The command value calculation unit 31 calculates a command value 82 that brings the response characteristics of the movement speed of the transport assistance device 100, until the input of the operation amount 80 (see FIG. 4 ) to the operator 102 is reflected as the movement speed of the transport assistance device 100, closer to the response characteristics expressed by the operation impedance models 40a and 40b.

[0056] The command value calculation unit 31 switches between the operational impedance model 40a and the operational impedance model 40b based on the determination result (acceleration or deceleration) of the acceleration / deceleration determination unit 32. When the determination result of the acceleration / deceleration determination unit 32 is "acceleration," the command value calculation unit 31 calculates the command value 82 using the operational impedance model 40a during acceleration. When the determination result of the acceleration / deceleration determination unit 32 is "deceleration," the command value calculation unit 31 calculates the command value 82 using the operational impedance model 40b during deceleration.

[0057] The operational impedance model 40a during acceleration and the operational impedance model 40b during deceleration have different speed response characteristics with respect to the input of the operation amount 80. Therefore, different response characteristics are realized during acceleration and deceleration. The operational impedance model 40a is constructed as a model that is considered to be ideal as the response characteristic during acceleration. The operational impedance model 40b is constructed as a model that is considered to be ideal as the response characteristic during deceleration. A plurality of selectable types may be prepared for each of the operational impedance model 40a during acceleration and the operational impedance model 40b during deceleration.

[0058] The operational impedance models 40a and 40b are expressed, for example, by a first-order lag transfer function model shown in equation (1). In formula (1), V ｃｍｄ represents the speed command value (command value 82). Lowercase s represents the Laplace operator, and uppercase S represents the detected manipulated variable value 81. K represents the gain in the first-order lag transfer function model. τ represents the time constant in the first-order lag transfer function model.

[0059] In one example, the operational impedance models 40a and 40b have different time constants τ. That is, the operational impedance model 40a during acceleration has a time constant τ during acceleration shown in equation (2). ａｃｃ The operational impedance model 40b during deceleration is set as follows: ｄｃｃ is set. This allows the command value calculation unit 31 to switch between the operational impedance models 40 a and 40 b based on the determination result by the acceleration / deceleration determination unit 32 .

[0060] The operational impedance model is not limited to a first-order transfer function representation, but may be a higher-order (second-order or higher) transfer function model.Furthermore, the operational impedance model is not limited to a model in the frequency domain (s domain) using a transfer function representation, but may be a model in the time domain using a state equation representation or the like.

[0061] <Explanation of Operation of Control Device> Fig. 6 is a flowchart illustrating the operation of the control device 20 of the transport assist device 100 according to the first embodiment. A control method for the transport assist device 100 according to the first embodiment shown in Fig. 1 to Fig. 5 will be described with reference to Fig. 6. The control method for the transport assist device 100 according to the first embodiment is executed by the control device 20.

[0062] First, the main control unit 21 calculates the control command value 83 for each drive wheel 10 based on the operation amount 80 input from the operation device 102 (steps S1 to S4).

[0063] Specifically, in step S1, the operation amount detection unit 30 detects the operation amount 80 input from the operation device 102 to the transport assist device 100. The operation amount detection unit 30 outputs an operation amount detection value 81. Next, in step S2, the acceleration / deceleration determination unit 32 determines whether the movement speed of the transport assist device 100 is accelerating or decelerating based on the detected operation amount detection value 81.

[0064] In step S3, the command value calculation unit 31 calculates a command value 82 for the transport assistance device 100 based on the operation amount detection value 81 and the determination result of acceleration or deceleration so that the response characteristics differ between acceleration and deceleration with respect to the operation amount detection value 81. First, the command value calculation unit 31 switches the operation model (operation impedance model 40a, operation impedance model 40b) that expresses the response of the movement speed of the transport assistance device 100 to the operation amount detection value 81 based on the determination result of acceleration or deceleration. Then, the command value calculation unit 31 uses the operation amount detection value 81 as an input and calculates a command value 82 for the speed of the transport assistance device 100 based on the switched operation impedance model (40a or 40b).

[0065] In step S4, the command value conversion unit 33 converts the command value 82 calculated by the command value calculation unit 31 into a control command value 83 for each drive wheel 10. In the example shown in Fig. 4, the command value conversion unit 33 multiplies the speed command value 82 calculated by the command value calculation unit 31 by the inverse matrix of the Jacobian matrix to obtain a control command value 83 for the angular velocity for each drive wheel 10 corresponding to the command value 82.

[0066] Next, the drive control unit 22 controls the drive wheels 10 of the transport assist device 100 based on the control command value 83 corresponding to the command value 82 (step S5).

[0067] First, each drive control unit 22 calculates a command value (drive current command value) 84 for the corresponding motor 11 based on the control command value 83 output by the main control unit 21. In the configuration example of FIG. 4 , each drive control unit 22 acquires a current angular velocity value 86 of the corresponding drive wheel 10 using the speed conversion unit 51. Next, each drive control unit 22 performs angular velocity control calculation using the speed control unit 50 based on the angular velocity control command value 83. That is, the subtractor 50a calculates the deviation between the angular velocity control command value 83 and the current angular velocity value 86, and the PI control unit 50b performs PI control based on the result of the subtraction by the subtractor 50a, thereby obtaining the command value (drive current command value) 84 for the motor 11.

[0068] Then, each drive control unit 22 (power conversion unit 52) ​​drives the motor 11 with a drive current 90 according to the command value 84. As a result, each drive control unit 22 controls the angular velocity of the drive wheels 10 based on the control command value 83 for the angular velocity of the drive wheels 10.

[0069] 7 is a graph G0 showing an example of the relationship between the traveling speed of the traveling tool and time. First, the response characteristics of the traveling tool 110 will be described. The response characteristics of the traveling speed of the traveling tool 110 may not be approximated by a single time constant (operation model).

[0070] Plot V1 shown in graph G0 in Fig. 7 represents the change in moving speed over time when the operator applies an external force to the traveling tool 110 to move it. The operator inputs a force F to move the traveling tool 110 as follows: First, no force F is input from time t0 to time t1 in Fig. 7. Next, the operator inputs force F in a stepped manner at time t1, maintains force F at a constant value from time t1 to t2, and no force F is input from time t2 onwards.

[0071] The response characteristics of the traveling speed with respect to the force F applied to the traveling tool 110 at this time are asymmetrical during acceleration and deceleration due to the influence of Coulomb friction and the like that exists between the driven wheels of the traveling tool 110 and the floor surface. In other words, there is a difference between the acceleration time tAC, which is the time it takes for the speed to reach a constant value between time t1 and time t2, and the deceleration time tDC, which is the time it takes for the traveling tool 110 to stop after time t2.

[0072] These characteristics of the response characteristics of the traveling tool 110 are expected to be the ideal operating impedance for the operator when moving the traveling tool 110 using the transportation assistance device 100. This is because the behavior of the traveling tool 110 when the operator applies an external force to the traveling tool 110 is similar to the behavior of the traveling tool 110 when the operator provides an operating input via the controller 102 (i.e., the operating feel). Furthermore, when moving the traveling tool 110 using the transportation assistance device 100, an operating impedance that allows for quick deceleration may be considered ideal from the perspective of avoiding collisions with obstacles (people, walls, etc.) during travel. In this way, the ideal operating impedance has at least different time constants during acceleration and deceleration.

[0073] As in the above-mentioned Non-Patent Document 1, when the operation impedance model is a model that outputs a first-order delay speed response to the operation amount and a single appropriate time constant is set, it is difficult to achieve different response characteristics during acceleration and deceleration. Furthermore, the heavier the traveling tool 110, the larger the time constant. In this case, the difference between the ideal time constant during acceleration and deceleration for the operator also becomes larger. Therefore, when controlling a transportation assist device using a transfer function model that can only set a single time constant regardless of acceleration or deceleration, this can cause a deviation between the ideal operation impedance and the actual travel speed change, resulting in poor operability for the operator.

[0074] Therefore, the control device 20 of the transport assistance device 100 according to the first embodiment can realize an ideal operation impedance by varying the response characteristics to the operation amount detection value 81 during acceleration and deceleration. FIG. 8 is a graph showing a first operation example of the transport assistance device 100 according to the first embodiment. FIG. 8 shows a graph G1 of the operation amount detection value 81, a graph G2 of the acceleration / deceleration determination result, and a graph G3 of the speed command value 82, all plotted on the same time axis. The horizontal axis of each of the graphs G1, G2, and G3 represents time. The vertical axis of the graph G1 represents the operation amount detection value, the vertical axis of the graph G2 represents the acceleration and deceleration determination results (binary data), and the vertical axis of the graph G3 represents the speed command value.

[0075] The example of Fig. 8 shows a case where the operation amount detected value 81 is changed stepwise at time t1, held constant between time t1 and time t2, and returned to the same value as between time t0 and time t1 after time t2 (i.e., a case where an operation equivalent to that shown in Fig. 7 is performed). Note that in this example, the case where the speed becomes constant is included in the case of acceleration. Plot V2 of graph G3 shows the change in speed command value 82 using operation impedance models 40a and 40b shown in equations (1) and (2).

[0076] As shown in FIG. 8 , in the first embodiment, acceleration and deceleration are switched between times t1 and t2, resulting in switching between the operational impedance models 40a and 40b used to calculate the command value 82. Plot V2 shows differences between the acceleration time tAC and the deceleration time tDC, reflecting the switching between the operational impedance models 40a and 40b. In other words, the time change (plot V2) of the command value 82 relative to the input of the manipulated variable 80 in the first embodiment matches or approximates the expected time change of the ideal operational impedance (plot V1 in graph G0 in FIG. 7 ). In this way, the control device 20 of the transport assistance device 100 according to the first embodiment can achieve drive control that approximates the ideal operational impedance, which has different time constants during acceleration and deceleration. As described above, the first embodiment improves the operability of the transport assistance device 100.

[0077] 9 is a graph showing a second operation example of the transport assist device 100 according to the first embodiment. The axes of the graph G4 of the operation amount detection value 81, the graph G5 of the acceleration / deceleration determination result, and the graph G6 of the speed command value 82 are the same as those of the graphs G1, G2, and G3 in FIG.

[0078] Fig. 9 illustrates a case where the operation amount detection value 81 of graph G4 is input so that the acceleration / deceleration changes irregularly, rather than being switched between two values, on and off, as shown in Fig. 8. Since the acceleration / deceleration determination result outputs only two values, acceleration or deceleration, the acceleration / deceleration determination unit 32 determines a period in which an input to maintain the speed or to additionally accelerate is made after an acceleration determination as "acceleration," and determines a period in which an input to maintain the speed or to additionally decelerate is made after a deceleration determination as "deceleration."

[0079] 9 , even when acceleration and deceleration change irregularly, the control device 20 inputs the detected manipulated variable value 81 to the manipulated variable impedance model (40a or 40b) switched depending on the determination result of acceleration or deceleration, and thereby calculates the command value 82 based on the formulas (1) and (2). As a result, even when acceleration and deceleration change irregularly, drive control is realized in which the response characteristics to the manipulated variable 80 differ between the periods of acceleration and deceleration.

[0080] Second Embodiment Next, the configuration of a control device 20A of a transport assist device 100 according to a second embodiment will be described. Fig. 10 is a block diagram showing an example of the configuration of a control device 20A of a transport assist device 100 according to the second embodiment. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0081] In the control device 20A of the transport assist device 100 according to the second embodiment, the command value calculation unit 31 calculates the command value 82 based on the operation amount detection value 81 and the determination result of the acceleration / deceleration determination unit 32, as well as the current state value of the transport assist device 100. The current state value of the transport assist device 100 is the current value of the movement speed of the transport assist device 100 (current speed value 87).

[0082] In the control device 20A, the main control unit 21 further includes a measurement value conversion unit 34. The speed conversion unit 51 of the drive control unit 22 outputs the calculated current angular velocity value 86 to the speed control unit 50 as well as to the measurement value conversion unit 34.

[0083] The measurement value conversion unit 34 converts the current angular velocity value 86 expressed in the wheel coordinate system into a current value of the moving velocity of the transportation assist device 100 expressed in an orthogonal coordinate system (current velocity value 87). For example, the measurement value conversion unit 34 multiplies the current angular velocity value 86 expressed in the wheel coordinate system by a Jacobian matrix to calculate the current velocity value 87 of the transportation assist device 100 expressed in an orthogonal coordinate system. The measurement value conversion unit 34 outputs the calculated current velocity value 87.

[0084] The command value calculation unit 31 calculates a command value 82 using the operation amount detection value 81, the determination result of the acceleration / deceleration determination unit 32, and the current speed value 87 calculated by the measurement value conversion unit 34 as input signals.

[0085] As a result, the command value calculation unit 31 calculates a command value 82 for the speed of the drive wheels 10 based on the operation amount detection value 81 and the current value of the movement speed (current speed value 87). An example of the command value calculation unit 31 that calculates the command value 82 based on the operation amount detection value 81 and the current speed value 87 will be described below.

[0086] <First Example of Command Value Calculation Based on Current Speed ​​Value> FIG. 11 is a diagram showing a first example of the command value calculation unit 31 in the second embodiment.

[0087] In the configuration example of FIG. 11 , the command value calculation unit 31 includes a correction calculation unit 41. For convenience, in FIG. 11 and FIG. 13 described later, the operational impedance models 40a and 40b are collectively shown as the operational impedance model 40. The operational impedance model 40 represents one of the operational impedance models 40a and 40b selected in accordance with the acceleration / deceleration determination result. The correction calculation unit 41 calculates a correction value 88a in accordance with the value of the current speed value 87. The command value calculation unit 31 outputs a value obtained by combining the calculation result 88b by the operational impedance model 40 and the calculation result (correction value 88a) by the correction calculation unit 41 as the speed command value 82.

[0088] 12 is a graph showing an example of calculation of the correction value 88a in the correction calculation unit 41. The vertical axis of the graph represents the correction value, and the horizontal axis represents the current speed value.

[0089] The correction calculation unit 41 determines whether the current state of the transport assist device 100 is accelerating or decelerating, using the current speed value 87 and the current speed value 87 from one sample before. That is, this example illustrates a case where the correction calculation unit 41 determines acceleration / deceleration based on the current speed value 87 actually occurring in the transport assist device 100, without using the acceleration / deceleration determination result based on the operation amount detection value 81. The correction calculation unit 41 outputs a correction value 88a corresponding to the relationship shown in FIG. 12 based on the acceleration / deceleration determination result and the current speed value 87.

[0090] In the example of FIG. 12 , the correction calculation unit 41 outputs a correction value 88a that is relatively larger at the beginning of acceleration / deceleration switching than at other times. That is, during acceleration, the current speed value 87 increases (changes to the right) from a certain value. At this time, the correction calculation unit 41 decreases the correction value 88a as the current speed value 87 increases on line L1. That is, the correction calculation unit 41 outputs the correction value 88a to the calculation result 88b by the operational impedance model 40 so as to increase the acceleration at the beginning of acceleration. Similarly, during deceleration, the current speed value 87 decreases (changes to the left) from a certain value. At this time, the correction calculation unit 41 decreases the magnitude (absolute value) of the correction value 88a (negative value) as the current speed value 87 decreases on line L2. That is, the correction calculation unit 41 outputs the correction value 88a to the calculation result 88b by the operational impedance model 40 so as to increase the negative acceleration at the beginning of deceleration. As a result, the response delay immediately after acceleration / deceleration switching is reduced. In this example, the correction calculation unit 41 corrects the speed command value 82 in the direction of making the correction value 88a a positive value in the low speed range during deceleration (i.e., immediately before stopping), so that the speed command value 82 is larger than the calculation result 88b (to slow the pace of deceleration). Also in this example, in the extremely low speed range where the current speed value 87 is approximately 0, the correction value 88a is not added, and the correction is essentially invalidated.

[0091] Note that there are other methods for determining the correction value 88a after determining whether acceleration or deceleration is occurring using the current speed value 87 and the current speed value 87 from one sample before, as described above. For example, there is a method using the acceleration / deceleration determination result based on the operation amount detection value 81. In this case, two correction values ​​88a corresponding to the current speed value 87 are prepared (a correction value 88a for acceleration and a correction value 88a for deceleration). Then, when combining with the calculation result 88b in the operation impedance model 40, either the correction value 88a for acceleration or the correction value 88a for deceleration is selected using the acceleration / deceleration determination result, and a combining calculation is performed.

[0092] The correction calculation unit 41 may perform the correction calculation using a calculation method other than the one exemplified here. For example, the correction calculation may be performed using only the current speed value 87 without distinguishing between acceleration and deceleration. The relationship between the current speed value 87 and the correction value 88a may be expressed as a relational expression using a nonlinear polynomial model shown as a curve.

[0093] <Second Example of Command Value Calculation Based on Current Speed ​​Value> FIG. 13 is a diagram showing a second example of the command value calculation unit 31 in the second embodiment.

[0094] In the configuration example of FIG. 13 , the command value calculation unit 31 includes a parameter calculation unit 42. Also in FIG. 13 , a calculation parameter 88c used in the operation impedance model 40 is a variable of the current speed value 87. For example, the gain K in equation (1) is expressed by the variable of the current speed value 87. The parameter calculation unit 42 calculates the calculation parameter 88c corresponding to the value of the current speed value 87. The command value calculation unit 31 reflects the calculation parameter 88c calculated by the parameter calculation unit 42 in the operation impedance model 40. The command value calculation unit 31 calculates a command value 82 based on the operation amount detection value 81 and the acceleration / deceleration determination result, using the operation impedance model 40 in which the calculation parameter 88c is reflected.

[0095] FIG. 14 is a graph showing an example of calculation of the calculation parameter 88c in the parameter calculation unit 42. The vertical axis of the graph represents the calculation parameter 88c (gain in this case), and the horizontal axis represents the current speed value. The parameter calculation unit 42 calculates the value of gain K in equation (1) based on the relationship between the current speed value 87 and the gain shown in FIG. 14. In FIG. 14, within the range of possible values ​​of the current speed value 87, the gain K for the current speed value 87 is large in the range from near the minimum value to the intermediate value (low value range). Therefore, when the current speed value 87 is in the low value range, the gain K in equation (1) is large, and as a result, the command value 82 is large relative to the detected manipulated variable value 81. As a result, acceleration (or deceleration) in the low speed range is improved, and response delay in the low speed range is reduced.

[0096] The relationship between the current speed value 87 and the gain K may be differentiated between acceleration and deceleration. In other words, the relationship between the current speed value 87 and the gain shown in FIG. 14 may be different between acceleration and deceleration. In this case, the operational impedance model 40a and the operational impedance model 40b differ in both the gain K and the time constant τ. The parameter calculation unit 42 calculates the gain K corresponding to the current speed value 87, for example, the gain K during acceleration. ａｃｃ , gain during deceleration K ｄｃｃ Then, the command value calculation unit 31 calculates the gain K during acceleration corresponding to the current speed value 87 based on the acceleration / deceleration determination result. ａｃｃ Or the gain K during deceleration ｄｃｃ Select one of the following.

[0097] Furthermore, the calculation parameter 88c calculated by the parameter calculation unit 42 is not limited to the gain K, and the time constant τ may be used as a variable of the current speed value 87. In this case, the parameter calculation unit 42 calculates the time constant τ during acceleration. ａｃｃ , time constant τ during deceleration ｄｃｃ Then, the command value calculation unit 31 calculates a value corresponding to the current speed value 87 as follows: ｄｃｃ (operation impedance model 40a) or τ during deceleration ｄｃｃ (operation impedance model 40b), the value of the time constant corresponding to the current speed value 87 is selected.

[0098] The other configurations of the second embodiment are similar to those of the first embodiment.

[0099] The actual moving speed of the transport assist device 100 may have a response delay with respect to the speed command value 82 due to the mechanical characteristics of the traveling implement 110 and the mechanical and electrical characteristics of the transport assist device 100. Even if the speed of the transport assist device 100 changes with a response delay, it is desirable to calculate the command value 82 that approaches the ideal operating impedance.

[0100] Therefore, in the second embodiment, the command value 82 is calculated using the current value (current speed value 87) of the state of the transport assist device 100 so as to suppress the effect of the response delay, thereby realizing drive control that approaches the ideal operational impedance. That is, in the calculation using the operational impedance model 40, the correction value 88a or the calculation parameter 88c corresponding to the current value (current speed value 87) is applied, thereby improving the ability of the speed of the transport assist device 100 to follow the operational impedance model 40 and realizing the ideal operational impedance.

[0101] In the second embodiment ( FIG. 10 ), the current speed value 87 is input to the command value calculation unit 31 as the current value of the state of the transportation assistance device 100. However, the present invention is not limited to this. For example, physical quantities calculated based on the angular acceleration and torque of the drive wheels 10 of the transportation assistance device 100, and physical parameters estimated by combining these quantities, may be input to the command value calculation unit 31 as the current value of the state of the transportation assistance device 100.

[0102] Third Embodiment Next, the configuration of a control device 20B of a transport assist device 100 according to a third embodiment will be described. Fig. 15 is a block diagram showing an example of the configuration of a control device 20B of a transport assist device 100 according to the third embodiment. In the third embodiment, the same components as those in the first or second embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0103] The control device 20B of the transport assist device 100 according to the third embodiment differs in the method of calculating command values ​​from the control device 20 (20A) according to the first or second embodiment. The following description will be based on the control device 20 of the transport assist device 100 according to the first embodiment, but the configuration of the third embodiment may also be applied to the control device 20A of the transport assist device 100 according to the second embodiment.

[0104] The command value calculation unit 31 of the control device 20B calculates a command value 82 according to the magnitude of the change in the operation amount detected value 81 based on the current value of the operation amount detected value 81 and the change in the operation amount detected value 81.

[0105] Specifically, the main control unit 21 further includes a time-change amount calculation unit 35. The time-change amount calculation unit 35 acquires the operation amount detection value 81 over time (at each sampling frequency) from the operation amount detection unit 30. The time-change amount calculation unit 35 calculates a time-change value 89 of the operation amount detection value 81 and inputs it to the command value calculation unit 31.

[0106] The time change amount calculation unit 35 calculates, for example, an inexact derivative d with respect to the operation amount detection value 81. That is, the calculation formula for the inexact derivative d with respect to the operation amount detection value 81 (defined as a variable S) is expressed by Equation (3). where τ D is the time constant of the inexact derivative, η is the inexact derivative input gain, and the lowercase s is the Laplace operator.

[0107] The time change amount calculation unit 35 outputs the obtained incomplete differential amount d as a time change value 89 of the operation amount detection value 81 .

[0108] The command value calculation unit 31 takes the current value of the operation amount detection value 81 and the time change value 89 as input, and calculates a command value 82 for the conveying assistance device 100 based on the operation impedance model 40 (40a or 40b, whichever is applied depending on acceleration or deceleration).

[0109] The command value calculation unit 31 calculates the command value 82 so that the command value 82 increases as the time-change value 89 increases. The method of calculating the command value 82 using the time-change value 89 is not particularly limited. For example, like the correction value 88a in the second embodiment, the time-change value 89 may be added to the calculation result 88b in the operational impedance model 40. Furthermore, some of the calculation parameters of the operational impedance model 40 may be used as variables for the time-change value 89. As a result, the command value 82 output from the command value calculation unit 31 becomes a value corresponding to the magnitude of the time-change value 89.

[0110] The other configurations of the third embodiment are similar to those of the first embodiment.

[0111] The third embodiment discloses a means different from that of the second embodiment for improving the ability of the behavior of the transport assistance device 100 to follow the operation impedance model 40 and realizing an ideal operation impedance when, for example, there is a response delay of the transport assistance device 100 to the command value 82. The third embodiment can improve the responsiveness of the transport assistance device 100 when the operation amount detected value 81 changes. That is, because a time change value 89 indicating the magnitude of the change in the operation amount detected value 81 is input to the command value calculation unit 31, it is possible to calculate a command value 82 that reduces the response delay even when the operation amount detected value 81 changes significantly.

[0112] In calculating the imperfect derivative d in equation (3), the imperfect derivative input gain η may be defined to have different values ​​during acceleration and deceleration. Similarly to the example shown in FIG. 10 , the imperfect derivative input gain η can be changed based on the current state of the transportation assistance device 100.

[0113] As described above, the control device 20 of the transport auxiliary device 100 of the embodiment comprises an operation amount detection unit 30 that detects an operation amount 80 input to the transport auxiliary device 100, an acceleration / deceleration determination unit 32 that determines whether the movement speed of the transport auxiliary device 100 is accelerating or decelerating based on an operation amount detection value 81 detected by the operation amount detection unit 30, and a command value calculation unit 31 that calculates a command value 82 for the transport auxiliary device 100 based on the operation amount detection value 81 and the determination result of the acceleration / deceleration determination unit 32 so that the response characteristics to the operation amount detection value 81 differ during acceleration and deceleration, and also comprises a main control unit 21 that outputs a control command value 83 for the drive wheels 10 of the transport auxiliary device 100 that corresponds to the command value 82, and a drive control unit 22 that controls the drive wheels 10 based on the control command value 83 output from the main control unit 21.

[0114] Furthermore, the control method for the transport auxiliary device 100 of the embodiment includes step S1 of detecting an operation amount 80 input to the transport auxiliary device 100, step S2 of determining whether the movement speed of the transport auxiliary device 100 is accelerating or decelerating based on the detected operation amount detection value 81, step S3 of calculating a command value 82 for the transport auxiliary device 100 based on the operation amount detection value 81 and the determination result of acceleration or deceleration so that the response characteristics to the operation amount detection value 81 differ during acceleration and deceleration, and step S5 of controlling the drive wheels 10 of the transport auxiliary device 100 based on a control command value 83 corresponding to the command value 82.

[0115] This allows the response characteristics of the transport assistance device 100 to the detected operation amount 81 to differ between when the transport assistance device 100 accelerates and when it decelerates. That is, even when the traveling tool 110 is moved by applying a force F (e.g., when examining step response), due to influences such as Coulomb friction between the driven wheels of the traveling tool 110 and the floor surface, there is a difference between the acceleration time tAC until the traveling tool 110 reaches a certain speed and the deceleration time tDC until the traveling tool 110 stops after the application of the external force is stopped. As a result, the response characteristics are not symmetrical between acceleration and deceleration. Furthermore, it has been discovered that, from the perspective of avoiding collisions with obstacles such as people or walls while traveling using the transport assistance device 100, rapid deceleration (rather than acceleration) is sometimes desirable. Based on this knowledge, by performing drive control that provides separate response characteristics during acceleration and deceleration, control of the transport assistance device 100 can be realized that further improves operability for the operator.

[0116] In addition, in the control device 20 of the transport assistance device 100 of the embodiment, the command value calculation unit 31 switches between operation models (operation impedance models 40a, 40b) that express the response of the movement speed of the transport assistance device 100 to the operation amount detection value 81 based on the judgment result of the acceleration / deceleration judgment unit 32.

[0117] Furthermore, in the control method for the transport assistance device 100 of the embodiment, in step S3 where the command value 82 is calculated, the operation model (operation impedance models 40a, 40b) that expresses the response of the movement speed of the transport assistance device 100 to the operation amount detection value 81 is switched based on the determination result of acceleration or deceleration.

[0118] According to this, by switching the operation model (operational impedance models 40 a, 40 b) between acceleration and deceleration, the response characteristics during acceleration and deceleration can be made to approach the response characteristics of separate ideal operation models (operational impedance models 40 a, 40 b), respectively. Furthermore, compared to realizing different response characteristics during acceleration and deceleration with a single operation model, it is easier to construct the operational impedance model 40 a during acceleration and the operational impedance model 40 b during deceleration.

[0119] In addition, in the control device 20 of the transport assistance device 100 of the embodiment, the command value calculation unit 31 outputs a command value 82 for the speed of the transport assistance device 100, and the drive control unit 22 performs angular velocity control for the drive wheels 10 based on a control command value 83 for the angular velocity of the drive wheels 10 corresponding to the speed command value 82.

[0120] In addition, in the control method for the transport auxiliary device 100 of the embodiment, in step S3 of calculating the command value 82, the command value 82 for the speed of the transport auxiliary device 100 is calculated based on the operation amount detection value 81, and in step S5 of controlling the drive wheels 10, the angular velocity of the drive wheels 10 is controlled based on a control command value 83 for the angular velocity of the drive wheels 10 that corresponds to the calculated speed command value 82.

[0121] According to this, the speed of the transport assistance device 100 is controlled as a control variable, so that the speed response characteristics of the traveling implement 110 caused by the transport assistance device 100 can be made closer to ideal response characteristics, which can further improve operability.

[0122] In addition, in the control device 20A of the transport assistance device 100 of the embodiment, the command value calculation unit 31 calculates the command value 82 based on the current value of the state of the transport assistance device 100 in addition to the operation amount detection value 81 and the judgment result of the acceleration / deceleration judgment unit 32.

[0123] Here, it is conceivable that the operation of the transport assistance device 100 will experience a response delay with respect to the command value 82 due to the mechanical characteristics of the traveling implement 110 and the mechanical and electrical characteristics of the transport assistance device 100. Therefore, by calculating the command value 82 based on the current value of the state of the transport assistance device 100, it is possible to improve the ability of the transport assistance device 100 to follow the ideal response characteristics even when the above-mentioned factors for the response delay are present.

[0124] In addition, in the control device 20A of the transport auxiliary device 100 of the embodiment, the current value of the state of the transport auxiliary device 100 is the current value of the movement speed of the transport auxiliary device 100 (current speed value 87), and the command value calculation unit 31 calculates the command value 82 of the speed of the transport auxiliary device 100 based on the operation amount detection value 81 and the current value of the movement speed (current speed value 87).

[0125] This improves the ability of the speed control of the transport assist device 100 to follow the ideal speed response characteristics based on the current value of the moving speed (current speed value 87). As a result, it is possible to prevent the operator from feeling that the behavior of the transport assist device 100 is sluggish (slower than expected).

[0126] In addition, in the control device 20B of the transport assistance device 100 of the embodiment, the command value calculation unit 31 calculates a command value 82 corresponding to the magnitude of the change in the operation amount detection value 81 (time change value 89) based on the current value of the operation amount detection value 81 and the change in the operation amount detection value 81 (time change value 89).

[0127] As a result, for example, when the change in the operation amount detection value 81 (time change value 89) is large, that is, when the operator wants to accelerate significantly, even if there is a response delay to the command value 82, the ability of the transport assistance device 100 to follow the ideal response characteristics for the operator can be improved by drive control according to the change in the operation amount detection value 81 (time change value 89).

[0128] (Modifications) The control device for the transport auxiliary device and the control method for the transport auxiliary device may be freely combined from each embodiment, or any component of each embodiment may be modified, or any component of each embodiment may be omitted.

[0129] For example, an example has been described in which the main control unit 21 outputs a control command value 83 for angular velocity and the drive control unit 22 performs speed control, but it is also possible for the main control unit 21 to output control command values ​​for other physical quantities such as acceleration, torque, or current, and for the drive control unit 22 to control these physical quantities, thereby controlling the transport assistance device 100 in accordance with the operation amount 80.

[0130] In addition, the main control unit 21 outputs a control command value 83 for the angle of each drive wheel 10, and the drive control unit 22 performs control based on the angle control command value 83, thereby making it possible to control the transport assistance device 100 in accordance with the operating amount 80.

[0131] For example, the command value calculation unit 31 calculates a command value 82 for the position and orientation of the transportation assistance device 100 as the behavior of the transportation assistance device 100 corresponding to the detected operation amount value 81, and the command value conversion unit 33 calculates a control command value 83 for the angle of each drive wheel 10 by inverse kinematics calculation from the position and orientation command value 82. The drive control unit 22 can also control the position and orientation by performing control so that the angle control command value 83 matches the measured angle value obtained from the angle sensor 12. The position and orientation represent at least one of the position and orientation of the transportation assistance device 100.

[0132] Furthermore, in the example shown, drive control unit 22 includes power conversion unit 52 and outputs drive current 90 to motor 11, but if motor 11 of drive wheel 10 includes a power conversion unit, drive control unit 22 does not need to be provided with power conversion unit 52. In that case, drive control unit 22 outputs command value 84 for motor 11 to motor 11. The power conversion unit of motor 11 generates drive current 90 for motor 11 based on command value 84.

[0133] REFERENCE SIGNS LIST 10 Drive wheel 11 Motor 12 Angle sensor 20 Control device 21 Main control unit 22 Drive control unit 30 Operation amount detection unit 31 Command value calculation unit 32 Acceleration / deceleration determination unit 33 Command value conversion unit 34 Measurement value conversion unit 35 Time change amount calculation unit 40, 40a, 40b Operation impedance model (operation model) 41 Correction calculation unit 42 Parameter calculation unit 50a Subtractor 50b PI control unit 50 Speed ​​control unit 51 Speed ​​conversion unit 52 Power conversion unit 80 Operation amount 81 Operation amount detection value 82 Command value 83 Control command value 84 Command value 85 Current angle value 86 Current angular velocity value 87 Current velocity value (current value of the state of the transport auxiliary device) 88a Correction value 88b Calculation result 88c Calculation parameter 89 Time change value 90 Driving current 100 Transport assist device 101 Housing 102 Operating device 103 Input unit 110 Traveling implement 111 Wheels 112 Handle 120 Connection unit 121 Connection unit main body 122 Mounting member

Claims

1. A control device for a transport auxiliary device comprising: an operation amount detection unit that detects an operation amount input to a transport auxiliary device; an acceleration / deceleration determination unit that determines whether the movement speed of the transport auxiliary device is accelerating or decelerating based on the operation amount detection value detected by the operation amount detection unit; a command value calculation unit that calculates a command value for the transport auxiliary device based on the operation amount detection value and the determination result of the acceleration / deceleration determination unit so as to have different response characteristics to the operation amount detection value during acceleration and deceleration; a main control unit that outputs a control command value for drive wheels of the transport auxiliary device corresponding to the command value; and a drive control unit that controls the drive wheels based on the control command value output from the main control unit.

2. The control device for a transport assist device according to claim 1, wherein the command value calculation section switches an operation model expressing a response of the moving speed of the transport assist device to the detected value of the operation amount based on a result of the determination by the acceleration / deceleration determination section.

3. The control device for a transport assistance device as described in claim 1, wherein the command value calculation unit outputs the command value for the speed of the transport assistance device, and the drive control unit performs angular velocity control for the drive wheels based on the control command value for the angular velocity of the drive wheels corresponding to the command value for the speed.

4. The control device for a transport auxiliary device according to claim 1, wherein the command value calculation section calculates the command value based on a current value of the state of the transport auxiliary device in addition to the detected value of the amount of operation and the judgment result of the acceleration / deceleration judgment section.

5. The control device for a transport auxiliary device according to claim 4, wherein the current value of the state of the transport auxiliary device is a current value of a moving speed of the transport auxiliary device, and the command value calculation unit calculates the command value for the speed of the transport auxiliary device based on the detected operation amount value and the current value of the moving speed.

6. A control device for a transport assistance device as described in any one of claims 1 to 5, wherein the command value calculation unit calculates the command value according to the magnitude of the change in the operation amount detection value based on a current value of the operation amount detection value and the change in the operation amount detection value.

7. A control method for a transport auxiliary device, comprising: a step of detecting an operation amount input to a transport auxiliary device; a step of determining whether the movement speed of the transport auxiliary device is accelerating or decelerating based on the detected operation amount detection value; a step of calculating a command value for the transport auxiliary device based on the operation amount detection value and the determination result of acceleration or deceleration so that the response characteristics to the operation amount detection value differ during acceleration and deceleration; and a step of controlling drive wheels of the transport auxiliary device based on a control command value corresponding to the command value.

8. The control method for a transport assist device according to claim 7, further comprising the step of: switching an operation model expressing a response of the moving speed of the transport assist device to the detected value of the amount of operation, based on a result of the determination of acceleration or deceleration, in the step of calculating the command value.

9. A method for controlling a transport auxiliary device as described in claim 7 or 8, wherein, in the step of calculating the command value, the command value for the speed of the transport auxiliary device is calculated based on the detected value of the amount of operation, and, in the step of controlling the drive wheels, the angular velocity of the drive wheels is controlled based on the control command value for the angular velocity of the drive wheels, which corresponds to the calculated command value for the speed.

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