Transport vehicle control device, transport vehicle and program

Abstract

To control torque generating on wheels suitably in a vehicle which is driven by using friction force of the wheels.SOLUTION: A transportation vehicle control device comprises a rotational position information acquisition part which acquires rotational position information containing information indicating rotation amount of a motor among two inertia resonance systems configured so as to contain drive wheels and the motor rotating and driving the drive wheels, a state amount observer which calculates torque due to influence of resonance on the basis of the rotational position information, a slip speed information acquisition part which acquires variation amount of slip speed of the drive wheels in prescribed period, a slip acceleration command generation part which calculates slip acceleration command value which is acceleration for restraining slip of the drive wheels on the basis of torque due to influence of the calculated resonance and the variation amount of the slip speed in the acquired prescribed period, and a torque command generation part which outputs motor torque command value on the motor on the basis of the calculated slip acceleration command value.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a transport vehicle control device, a transport vehicle, and a program. [Background technology]

[0002] Conventionally, in vehicles that are driven by the frictional force generated between the wheels and the ground as a result of driving the wheels in rotation, there has been technology that prevents the wheels from spinning by controlling the torque generated in the wheels when it is determined that the wheels are spinning (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-204956 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the above-mentioned conventional technology, control is performed by generating a stabilizing torque in the wheels so that the slip acceleration obtained by differentiating the slip velocity, which is the difference between the peripheral speed of the wheels and the vehicle body speed, becomes zero. However, this technology is based on the premise that the drive system between the motor and the wheels is rigidly connected. In a drive system in which the relationship between the motor and the wheels is expressed as a two-inertia resonance system, such as in a transport vehicle, there is an issue that the torque due to resonance cannot be ignored.

[0005] The present invention has been made in consideration of the above-mentioned situation, and aims to provide a transport vehicle control device, a transport vehicle, and a program that are capable of appropriately controlling the torque generated in the wheels in a vehicle driven using the frictional force of the wheels. [Means for solving the problem]

[0006] A transport vehicle control device according to one embodiment of the present invention includes a two-inertia resonant system including a drive wheel and a motor that drives the drive wheel to rotate, and includes: a rotational position information acquisition unit that acquires rotational position information including information indicating the rotation amount of the motor; a state quantity observer that calculates torque due to the effect of resonance based on the rotational position information; a slip speed information acquisition unit that acquires an amount of change in slip speed of the drive wheel over a predetermined period of time; a slip acceleration command generation unit that calculates a slip acceleration command value, which is an acceleration for suppressing slip of the drive wheel, based on the calculated torque due to the effect of resonance and the acquired amount of change in the slip speed over a predetermined period of time; a torque command generation unit that calculates a motor torque command value, which is a command value for torque to be applied to the motor based on the calculated slip acceleration command value; and a torque command value output unit that outputs the generated motor torque command value to the motor.

[0007] In addition, a transport vehicle control device according to one embodiment of the present invention further includes a slip acceleration adjustment unit that calculates a slip acceleration adjustment value based on the torque due to the effect of resonance calculated by the state quantity observer, and the slip acceleration command generation unit calculates the slip acceleration command value based on the calculated slip acceleration adjustment value.

[0008] In addition, a transport vehicle control device according to one embodiment of the present invention further includes a torsional torque control unit that calculates a current command value for a current flowing through the motor based on the torque due to the effect of resonance calculated by the state quantity observer, the rotational speed of the motor based on the rotational position information, and the slip acceleration command value, and the torque command generation unit calculates the motor torque command value based on the calculated current command value.

[0009] In addition, in a transportation vehicle control device according to one embodiment of the present invention, the state quantity observer further calculates an angular velocity estimation value, which is a value estimating the speed of each of the drive wheels based on the rotational position information, and further includes a slip acceleration control unit that calculates a torsional torque command value based on the angular velocity estimation value calculated by the state quantity observer and the slip acceleration command value calculated by the slip acceleration command generation unit, and the torsional torque control unit calculates the current command value based on the torsional torque command value.

[0010] A transport vehicle according to one aspect of the present invention includes the transport vehicle control device described above, the motor controlled by the transport vehicle control device, and the drive wheels rotationally driven by the motor.

[0011] Moreover, a program according to one aspect of the present invention causes a computer to execute the following steps: a rotational position information acquisition step of acquiring rotational position information including information indicating an amount of rotation of the motor in a two-inertia resonant system including a drive wheel and a motor that drives and rotates the drive wheel; a state quantity observer execution step of calculating torque due to the effect of resonance based on the rotational position information; a slip acceleration acquisition step of acquiring an amount of change in slip velocity of the drive wheel over a predetermined period of time; a slip acceleration command generation step of calculating a slip acceleration command value, which is an acceleration for suppressing slip of the drive wheel, based on the calculated torque due to the effect of resonance and the acquired amount of change in the slip velocity over the predetermined period of time; and a torque command generation step of outputting a motor torque command value to the motor based on the calculated slip acceleration command value. Effect of the Invention

[0012] According to the present invention, it is possible to provide a transport vehicle control device, a transport vehicle, and a program capable of suitably controlling the torque generated in the wheels of a vehicle driven by the frictional force of the wheels. [Brief description of the drawings]

[0013] [Figure 1]1 is a perspective view for illustrating a schematic appearance of an example of a transporter vehicle according to an embodiment. FIG. [Diagram 2] 3 is a functional configuration diagram illustrating an example of a functional configuration of a transporter vehicle according to the embodiment. FIG. [Diagram 3] 1 is a conceptual diagram of a two-inertia resonant system according to an embodiment. [Figure 4] 4 is a diagram for explaining an example of a power transmission means of the transport vehicle according to the embodiment. FIG. [Diagram 5] 4 is a flowchart for explaining a series of operations of the transport vehicle control device according to the embodiment. [Figure 6] FIG. 4 is an example of a characteristic diagram of slip velocity and tangential force torque according to the embodiment. [Figure 7] FIG. 11 is a diagram for explaining an example of linearization of a characteristic diagram of slip velocity and tangential force torque according to the embodiment. [Figure 8] FIG. 2 is a block diagram for explaining functions of a transport vehicle control device according to the embodiment. [Figure 9] 4 is a diagram for explaining parameters used in a simulation of the transport vehicle control device according to the embodiment. FIG. [Figure 10] FIG. 11 is a slip velocity-tangential force coefficient characteristic diagram used in a simulation of the transport vehicle control device according to the embodiment. [Figure 11] FIG. 11 is a diagram showing simulation results of the axial current, the motor side speed, and the torsional torque when the control according to the embodiment is used. [Figure 12] FIG. 13 is a diagram showing a simulation result of a slippage determination signal when the control according to the embodiment is used. [Figure 13] FIG. 11 is a diagram showing simulation results for slip speed, wheel speed, running speed, and tangential force when the control according to the embodiment is used. [Figure 14] FIG. 13 is a diagram showing a simulation result of a slip acceleration command value and a slip velocity when the control according to the embodiment is used. [Figure 15]FIG. 11 is a diagram showing simulation results for the axial current, the motor side speed, and the torsional torque when the control according to the embodiment is not used. [Figure 16] FIG. 13 is a diagram showing a simulation result of a slip determination signal when the control according to the embodiment is not used. [Figure 17] FIG. 11 is a diagram showing simulation results for slip speed, wheel speed, running speed, and tangential force when the control according to the embodiment is not used. [Figure 18] FIG. 1 is a block diagram for explaining anti-slip control according to a conventional technique. [Figure 19] 1 is a flowchart for explaining anti-slip control according to a conventional technique. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [Prior Art] First, an overview of anti-slip control according to the conventional technology and problems associated with the conventional technology will be described with reference to Fig. 18 and Fig. 19. The conventional anti-slip control is a technology used, for example, in drive control of trains.

[0015] 18 is a block diagram for explaining anti-slip control according to the conventional technology. The function of the anti-slip control device 9 will be explained with reference to the diagram. The anti-slip control device 9 includes a control system 90 and a drive system 91. The control system 90 includes a speed detector 92, a disturbance observer 93, a torque reduction amount determiner 94, a slip acceleration command generator 95, a running acceleration estimator 96, a slip acceleration controller 97, and a torque command generator 98.

[0016] The drive system 91 includes a motor that rotates the wheels, a pulley attached to the rotary shaft of the motor, a gear that connects the pulley and the wheels, and the wheels connected to the gear. The drive system 91 is controlled by the control system 90. Specifically, the drive system 91 is controlled by a torque command value τ Mref The drive system 91 is provided with a rotary encoder (not shown) for detecting the rotation speed of the motor, and detects the angular position θ of the output shaft of the motor. M The data representing the above is output to the control system 90.

[0017] The speed detector 92 detects the angular position θ M The speed detector 92 periodically receives data representing the received angular position θ M Based on this, the angular position θ M By calculating the rate of change of the rotation speed (angular speed of the motor shaft) ω M The speed detector 92 calculates the calculated rotation speed ω M to the disturbance observer 93 and the running acceleration estimator 96. The running acceleration estimator 96 estimates the acquired rotation speed ω M From the motor rotation speed, i.e. the running speed v L Estimate.

[0018] The disturbance observer 93 detects the acquired rotation speed ω M and the current command value i q ref Based on and, the tangential force torque τ T The disturbance observer 93 calculates the calculated tangential force torque τ T to the torque reduction amount determiner 94 and to the adder 975. The torque reduction amount determiner 94 determines the tangential force torque τ T The torque reduction amount determiner 94 obtains the obtained tangential force torque τ T Based on this, the torque reduction amount is the reduction torque τ TS Calculate.

[0019] The slip acceleration command generator 95 calculates the amount of change in the slip velocity Δv S , i.e., the slip acceleration. The slip acceleration command generator 95 obtains the obtained slip acceleration and the calculated pull-down torque τ TS Based on this, the acceleration command value v' S ref Calculate. The slip acceleration controller 97 calculates the acceleration command value v' S ref and the estimated driving speed v L Based on this, the motor driving torque τ M ref Calculate. The torque command generator 98 generates the calculated motor drive torque τ M ref is output to the drive system 91.

[0020] 19 is a flow chart for explaining anti-slip control according to the conventional technique. The operation of the anti-slip control device 9 will be explained with reference to the same figure. (Step S91) The anti-slip controller 9 judges whether or not the rotation speed of the motor exceeds the threshold value of the driving wheel acceleration. If the rotation speed of the motor exceeds the driving wheel acceleration, the anti-slip controller 9 advances the process to step S92. (Step S92) The anti-slip control device 9 determines that the wheels are slipping, and advances the process to step S93. (Step S93) The anti-slip control device 9 determines, in a feedforward manner, a slip acceleration command for suppressing slipping. (Step S94) The anti-slip controller 9 determines the amount of torque to be reduced based on the determined slip acceleration command. The anti-slip controller 9 controls the rotation speed of the motor based on the determined amount of torque to be reduced.

[0021] The anti-slip control device 9 was able to detect wheel slippage and suppress the slippage by feedforward. The systems controlled by the anti-slip control device 9 are limited to drive systems such as trains in which the motor pulley and wheels are rigidly connected. In the case of a two-inertia resonance system in which objects with large mass such as the motor pulley and wheels are connected by elastic members such as thin shafts and belts, the anti-slip control device 9 according to the conventional technology cannot take into account the effects of resonance. An object of this embodiment is to provide a control method that can suppress the influence of resonance and perform suitable control even in the case of a two-inertia resonance system.

[0022] [Embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The embodiment described below is merely an example, and the embodiment to which the present invention is applied is not limited to the following embodiment. Due to the limited characters that can be used, in the formulas below, variables marked with a hat symbol (variables expressed in English symbols or Greek letters) may be written as "(English symbol or Greek letter)^(hat)" in the text of this specification. In the drawings, first derivatives are indicated by a dot on the symbol, but in the specification they may be indicated by a "゜" and a dash (') indicates an adjustment value.

[0023] [Transport vehicle] 1 is a perspective view for illustrating a schematic external view of an example of a transporter vehicle according to an embodiment, with reference to which a transporter vehicle 1 according to an embodiment will be described. The transport vehicle 1 is transported by being pushed or pulled by an operator. The transport vehicle 1 has at least one wheel or tire (hereinafter referred to as a drive wheel) that is power-assisted by a motor, and is driven by the frictional force between the drive wheel and the ground. The ground includes the bottom of the water, such as the bottom of the sea or lake, regardless of the topography, such as flat or sloping. In particular, the ground includes farmland, such as rice paddies, crop cultivation land, grassland, and pasture, and includes muddy ground.

[0024] Specifically, the transport vehicle 1 may be a hand-pushed transport cart (push cart, also known as a cat or cat cart). The transport vehicle 1 is used to transport agricultural products and materials at sites such as farmland and construction sites. The transport vehicle 1 needs to have at least one drive wheel, and may have two, three, four or more drive wheels. Furthermore, the transport vehicle 1 may specifically be a two-wheeled vehicle such as a handcart pulled by a worker.

[0025] The transport vehicle 1 includes at least one drive wheel 32, a loading platform 21, a handle 22, and a control box 23. An operator loads agricultural produce, materials, and other cargo onto the loading platform 21 and transports the loaded cargo. The transport vehicle 1 obtains its main power by being pushed by an operator holding the handle 22.

[0026] The drive wheels 32 rotate when an operator grasps the handle 22 and pushes them, generating friction between the ground and the surface of the drive wheels 32. The drive wheels 32 are also driven (i.e., power assisted) by the transport vehicle control device 10. The control box 23 houses the transport vehicle control device 10. The transport vehicle control device 10 drives a motor (not shown) to control the drive wheels 32. Specifically, the transport vehicle control device 10 performs control for power assist.

[0027] 2 is a functional configuration diagram for explaining an example of the functional configuration of a transport vehicle according to an embodiment. With reference to the diagram, an example of the functional configuration of a transport vehicle 1 according to an embodiment will be explained. The transport vehicle 1 includes a transport vehicle control device 10, a motor 31, and drive wheels 32 as functional components. In the following description, the transport vehicle control device 10 is also referred to as a control system 12, and the motor 31 and drive wheels 32 are also referred to as a drive system 13. The drive system 13 may also include other power transmission means such as gears and belts.

[0028] The transport vehicle control device 10 acquires motor information IM from the motor 31, and acquires driving wheel information IW from the driving wheels 32. The transport vehicle control device 10 generates control information IC based on the acquired motor information IM and driving wheel information IW, and outputs the control information IC to the motor 31 to control the motor 31. The motor 31 obtains control information IC from the transport vehicle control device 10 and rotates the drive wheels 32. The motor 31 transmits power to the drive wheels 32 by a power transmission means (not shown) such as a gear. Information on the power to be transmitted is also referred to as drive information ID. The motor 31 may be, for example, a servo motor. The drive wheels 32 are driven by the motor 31. The drive wheels 32 may be, for example, rubber tires.

[0029] [Bi-inertial resonant system] Here, the motor 31 and the drive wheels 32 each have mass, and the power generated by the motor 31 is transmitted to the drive wheels 32 by a power transmission means such as a gear, a belt, a shaft, or a belt. For example, when the power transmission means includes a thin shaft or an elastic belt, the drive system 13 is expressed as a two-inertia resonance system. Hereinafter, an example of the case where the drive system 13 is expressed as a two-inertia resonance system will be described with reference to Figures 3 and 4.

[0030] 3 is a conceptual diagram of a two-inertia resonant system according to an embodiment of the present invention. With reference to the drawing, the physical forces occurring in the two-inertia resonant system will be described. On the motor 31 side, the moment of inertia on the motor side is the moment of inertia J M [kgm 2 ], and the viscous friction on the motor side is viscous friction D M [N S / m], and the spring constant is the spring constant K S [N / m], the motor rotation speed is the rotation speed ω M [rad / s], the motor drive torque is the drive torque τ M [Nm]. The torque due to the effect of resonance is expressed as torque τ S [Nm], gear ratio R g It is written as follows.

[0031] Also, on the driving wheel 32 side, the moment of inertia on the driving wheel side is defined as the moment of inertia J L [kgm 2 ], and the viscous friction on the driving wheel side is viscous friction D L [N S / m], and the rotational speed of the drive wheel is the rotational speed ω L [rad / s], the driving torque on the driving wheel side is the driving torque τ M [Nm]. The tangential force torque is expressed as tangential force torque τ t [Nm] and the tangential force F t [N]. The travel speed of the transport vehicle 1 is v L[m / s], the rotational speed of the driving wheel is the driving wheel rotational speed v d [m / s], and gravitational acceleration is g [m / s 2 ], the force with which the worker pushes the transport vehicle 1 is F human [N], the weight of the vehicle borne by the axle of the drive wheels is the vehicle weight M1 [kg], the weight on the axle of the drive wheels is the axle weight W1 [N], and the running resistance is the running resistance F d [N], the tangential force coefficient μ(v s ) should be written.

[0032] Generally, since it is difficult for the motor 31 alone to output high torque, a reduction gear is attached between the motor 31 and the drive wheels 32 to obtain a high torque output instead of reducing the rotation speed. In this case, the attached reduction gear may cause resonance between the motor 31 and the drive wheels 32. Therefore, it is necessary to control the shaft torsion torque caused by the resonance.

[0033] 4 is a diagram for explaining an example of a power transmission means of the transporter vehicle according to the embodiment, with reference to which an example of the power transmission means of the transporter vehicle 1 will be explained. The pulley 34 receives power from the motor 31 and transmits the power to the rubber tire 35. The rubber tire 35 is an example of the drive wheel 32. The pulley 34 and the rubber tire 35 are connected by a belt 36. Because the belt 36 has elasticity, a delay occurs in transmitting the power generated by the motor 31. In other words, the pulley 34 and the rubber tire 35 are represented by a two-inertia system. In this embodiment, by having the transport vehicle control device 10, the torque generated in the drive wheels 32 can be suitably controlled even in a transport vehicle 1 having a partially elastic power transmission means as shown in the figure.

[0034] [A series of operations of the transport vehicle control device] 5 is a flow chart for explaining a series of operations of the transport vehicle control device according to the embodiment, which will be described with reference to the drawing. (Step S110) The transport vehicle control device 10 calculates the driving wheel rotation speed v d and obtain the wheel rotation speed v d The transport vehicle control device 10 compares the driving wheel rotation speed v d exceeds the preset threshold, the process proceeds to step S120. (Step S120) The transport vehicle control device 10 determines that the drive wheels 32 have started to spin, that is, have "slipped."

[0035] (Step S130) The transport vehicle control device 10 performs vibration suppression control, which will be described later, and maintains the maximum value of the feedback amount. (Step S140) The transport vehicle control device 10 calculates a "slip acceleration command value" capable of suppressing slippage, with a priority given to the maximum value of the feedback amount. (Step S150) The transport vehicle control device 10 judges whether or not the torque of the "slip acceleration command value" is sufficient. If the torque is not sufficient (i.e., step S150; NO), the transport vehicle control device 10 advances the process to step S160. If the torque is sufficient (i.e., step S150; YES), the transport vehicle control device 10 advances the process to step S170. (Step S160) The transport vehicle control device 10 corrects the "slip acceleration command value" with the slip acceleration adjustment value. (Step S170) The transport vehicle control device 10 determines the amount of torque to be reduced based on the determined "slip acceleration command value."

[0036] [Calculation of acceleration command value] Next, calculation of the acceleration command value will be described with reference to FIGS. FIG. 6 shows the sliding velocity v S and tangential torque τ t This is an example of a characteristic diagram of the slip velocity v S , the vertical axis is the tangential force torque τ t As the slip velocity v S and tangential torque τ t This shows the relationship between:

[0037] In Fig. 6, the positive slope area indicates the slip velocity v S As the tangential torque τ increases, t The area where the slope is negative is called the adhesion area. On the other hand, the area where the slope is negative is called the adhesion area. S As the tangential torque τ increases, t This is the area where the torque decreases and is called the slip area.

[0038] In order to prevent operation in the slip region and achieve a high tangential force utilization rate, it is necessary to reduce the torque and return to operation in the adhesion region. Reducing the torque and returning to operation in the adhesion region can be achieved, for example, by reducing the amount of current applied to the motor 31. By reducing the torque, the slip velocity v S and tangential torque τ t The characteristic is lowered to the characteristic shown by the symbol W12.

[0039] FIG. 7 is a diagram for explaining an example of linearization of a characteristic diagram of slip velocity and tangential force torque according to the embodiment. With reference to the diagram, S and tangential torque τ t An example of linearization of the characteristic diagram of the slip velocity v before linearization will be described. S and tangential torque τ t Fig. 7(B) shows the characteristic diagram of the linearized sliding velocity v S and tangential torque τ t The characteristic diagram is shown below.

[0040] As shown in Figure 7(A), the slip velocity v S and tangential torque τ t The characteristics of are nonlinear, and it is not easy to define specific values ​​and coefficients. Therefore, a linear approximation is performed as shown in Figure 7(B). When a linear approximation is performed, the characteristics of the slip region are expressed as the following formula (1).

[0041]

number

[0042] Here, the tangential torque τ tS is the slope during spin, and this value is thought to change depending on the road surface conditions (e.g., dry asphalt, wet asphalt, mud, etc.). The maximum tangential force torque on a wet asphalt road surface is thought to be smaller than the maximum tangential force torque on a dry asphalt road surface. Tangential force torque τ tS To find this, use the tangential torque τ t can be differentiated.

[0043] From the above equation (1) and the equation of motion of the wheel model, the following equation (2) can be derived.

[0044]

number

[0045] In the above equation (2), the running resistance does not change suddenly, and the vehicle acceleration is assumed to be almost constant. L If it matches the actual value, it can be summarized as equation (3) below.

[0046]

number

[0047] From the above, the slip velocity v S The initial value of the slip velocity v S0 Using this, we can obtain the following equation (4).

[0048]

number

[0049] Also, for each sample, for a certain period of time Δ t Slip velocity v S The change in Δv S The slip acceleration vS Since the slip acceleration command value v S ref is expressed as the following equation (5).

[0050]

number

[0051] The slip acceleration command value v° expressed by the above formula (5) S ref In this embodiment, the transport vehicle control device 10 performs state feedback and vibration suppression control caused by resonance frequency in addition to calculating the acceleration command value described above.

[0052] Here, the control according to the conventional technology and the anti-slip control for the transport vehicle 1 according to this embodiment have different priorities. In the control according to the conventional technology, a torque is applied to accelerate the vehicle body, and when a slip is detected, the torque is switched to a pull-down torque. Therefore, according to the conventional technology, the "vehicle body acceleration torque" and the "pull-down torque" are given priority. On the other hand, in the anti-slip control for the transporter vehicle 1 according to this embodiment, the torque amount that suppresses the vibration component caused by the resonance frequency is prioritized in both the slip region and the adhesion region.

[0053] According to this embodiment, when the torque is reduced, the torque amount that suppresses the vibration component caused by the resonance frequency is prioritized, so a torque reduction to pull back to the adhesion region may be required. In that case, it is necessary to adjust the slope of the slip acceleration. Therefore, in the above-mentioned formula (5), the slip acceleration adjustment value v°' S The value obtained by adding the above is the slip acceleration command value v゜. S ref The slip acceleration command value v° when the slope of the slip acceleration is adjusted S ref is shown in equation (6) below.

[0054]

number

[0055] [Vibration suppression control] Next, vibration suppression control will be described with reference to FIG. 8 is a block diagram for explaining the function of the transport vehicle control device according to the embodiment, and vibration suppression control will be explained with reference to the diagram. The control system 12 has, as its functional configuration, a rotational position information acquisition unit 111, a speed detector 112, a state quantity observer 113, a slip acceleration regulator (slip acceleration adjustment unit) 114, a torque reduction amount determiner 115, a slip speed information acquisition unit 116, a slip acceleration command generator (slip acceleration command generation unit) 117, a running acceleration estimator 118, a slip acceleration controller (slip acceleration control unit) 119, a torsional torque controller (torsion torque control unit) 120, a torque command generator (torque command generation unit) 121, and a torque command value output unit 122.

[0056] The rotational position information acquisition unit 111 acquires rotational position information from the motor 31. The rotational position information is information indicating the amount of rotation of the motor 31 (for example, the angular displacement θ of the motor-side shaft) in a two-inertia resonance system including the drive wheels 32 and the motor 31 that drives the drive wheels to rotate. M The rotational position information may be, for example, an output value of a rotary encoder (not shown) provided in the motor 31, or an output value of a resolver.

[0057] The speed detector 112 acquires the rotational position information from the rotational position information acquisition unit 111 at a predetermined cycle. Based on the acquired rotational position information, the speed detector 112 detects the rotational speed ω M The speed detector 112 calculates, for example, the angular displacement θ M The data representing the rotation speed ω is obtained as an analog signal, and the obtained analog signal is differentiated using a differentiator or the like to obtain the rotation speed ω M may be calculated.

[0058] The state quantity observer 113 calculates the torque τ due to the effect of resonance based on the rotational position information acquired by the rotational position information acquisition unit 111. S ^(hat) and the estimated angular velocity of the load shaft ω L Specifically, the state quantity observer 113 calculates the rotation speed ω M and obtain the rotation speed ω M Based on the effect of resonance on the torque τ S ^(hat) is calculated. The angular velocity estimate ω of the load shaft is calculated. L ^ (hat) is an estimated value of each speed of the drive wheels 32.

[0059] The slip acceleration regulator 114 adjusts the tangential force torque estimate value τ t ^(hat) and the torque τ due to the effect of resonance S Based on ^(hat), the slip acceleration adjustment value v゜' S Calculate.

[0060] The torque reduction amount determiner 115 determines the tangential force torque estimate τ t ^(hat) and the torque τ due to the effect of resonance S Based on ^(hat), the torque reduction amount τ ts Here, the torque reduction amount τ ts Pull down torque τ S’ Also written as pull-down torque τ S’ is expressed by the following equation (7).

[0061]

number

[0062] The slip speed information acquisition unit 116 calculates the slip speed difference value Δv S The slip speed difference value Δv S That is, the slip velocity v of the driving wheel 32 S is the amount of change in a given period of time.

[0063] The slip acceleration command generator 117 receives the slip acceleration adjustment value v°' calculated by the slip acceleration adjuster 114. S and the speed v acquired by the slip speed information acquisition unit 116. S The slip velocity difference value Δv S Based on this, a slip acceleration command value v°, which is an acceleration for suppressing slip of the drive wheels 32, is calculated. S ref Calculate. Here, the slip acceleration adjustment value v S is the torque τ due to the effect of resonance calculated by the state quantity observer 113. S In other words, the slip acceleration command generator 117 calculates the torque τ due to the effect of resonance calculated by the state quantity observer 113. S Based on ^(hat), the slip acceleration command value v゜ S ref Calculate.

[0064] The running acceleration estimator 118 estimates the angular velocity ω of the load side shaft calculated by the state quantity observer 113. L Based on the above and pre-stored information such as the diameter of the driving wheel 32, the estimated speed v of the electric transport vehicle in the traveling direction is calculated. L Calculates ^(hat).

[0065] The slip acceleration controller 119 controls the slip acceleration command value v° calculated by the slip acceleration command generator 117. S ref and v calculated by the driving acceleration estimator 118 L Based on ^(hat), the torsional torque command value τ S ref Calculate.

[0066] Here, the pull-down torque τ S’ must be in the region where the slip acceleration is negative, so the following equation (8) must be satisfied.

[0067]

number

[0068] Sliding acceleration v' that satisfies the above equation (8) S If it is possible to set the slip acceleration command value v゜, as shown in the following equation (9), S ref Using the torsional torque command value τ S ref can be set.

[0069]

number

[0070] The torsional torque controller 120 controls the rotation speed ω M and the torque τ due to the effect of resonance calculated by the state quantity observer 113. S ^(hat), and the torsional torque command value τ calculated by the slip acceleration controller 119 S ref Based on this, the torque current command value I q ref Calculate the torque current command value I q ref In other words, this is the current command value of the current flowing through the motor 31.

[0071] The torque command generator 121 generates the torque current command value I q ref Based on this, the motor side torque command value τ M ref Calculate the torque current command value I q ref is the slip acceleration command value v S ref That is, the torque command generator 121 calculates the slip acceleration command value v S ref A motor torque command value is generated for the motor 31 based on the above. The torque command value output unit 122 outputs the generated motor-side torque command value τ M ref Output.

[0072] [simulation] Next, a simulation result of the transport vehicle control device 10 according to the present embodiment will be described with reference to FIG. 9 to FIG. 9 is a diagram for explaining parameters used in a simulation of the transport vehicle control device according to the embodiment. human was performed using a step signal of 10[N]. In addition, the simulation time step T Ssim to 1.0×10 -6 [S], Simulation discrete time step T S to 1.0×10 -4 [S], Simulation slip calculation step ΔT S [S] to 1.0×10 -3 , the slope of the characteristic τ ls -2.2×10 -2 , the slip velocity difference Δvs is 1.0×10 -2 The simulation was performed in [rad / S].

[0073] First, an example of a simulation result in the case where the anti-slip control according to this embodiment is used will be described with reference to FIGS. FIG. 10 is a slip velocity-tangential force coefficient characteristic diagram used in a simulation of the transport vehicle control device according to the embodiment. The slip velocity-tangential force coefficient characteristic diagram will be described with reference to the same figure. The same figure shows the slip velocity v S is shown on the horizontal axis and the tangential force coefficient on the vertical axis. Figure 10(B) shows the same as Figure 10(A) except for the slip velocity v S This is an enlarged view of the range from -5[rad / s] to 5[rad / s]. From Fig. 10(B), the slip velocity v S It can be seen that the maximum tangential force coefficient μ is obtained when the sliding velocity v exceeds 0.6 [rad / s].S In other words, the threshold value for wheel acceleration is 0.6.

[0074] Fig. 11 shows the simulation results of the axial current, motor side speed, and torsional torque when the control according to the embodiment is used. Fig. 11(A) shows the axial current value of the motor 31, Fig. 11(B) shows the motor side speed, and Fig. 13(C) shows the torsional torque, all of which change over time when the horizontal axis is time [S (seconds)]. No slip occurs up to about 0.65 [S (seconds)]. During this period, backdrive operation (zero command torsional torque control) is performed. After 0.65 [S], slippage is detected, and the anti-slip control according to this embodiment is performed. As a result of the anti-slip control, it can be seen that the torque is reduced at the time when slippage is detected. It can also be seen that after the torque is reduced, the torque is increased again.

[0075] 12A and 12C are diagrams showing simulation results of the slippage determination signal when the control according to the embodiment is used. FIG. 12A and FIG. 12C show the change in the slippage determination signal over time. FIG. 12C shows the change in the drive wheel rotation speed v d Shows the change in. It can be seen that the driving wheel 32 starts to slip at 0.65 [S]. As a result of the anti-slip control, the driving wheel rotation speed v d It is clear that the is changing.

[0076] FIG. 13 is a diagram showing simulation results for slip velocity, wheel speed, running speed, and tangential force when the control according to the embodiment is used. S , FIG. 13(B) shows the speed v of the drive wheel 32. d , FIG. 13(C) shows the travel speed v L , Fig. 13(D) shows the tangential force F t The time changes of are shown. Sliding velocity v S starts accelerating gradually from 0.2 [S], and after 0.65 [S] where slippage occurs, it decelerates once, but starts accelerating again. Also, the speed v of the drive wheel 32 d The vehicle also decelerates after 0.65 [S] when the slip occurs, but then starts accelerating again. L The acceleration gradually increases, and as a result of the anti-slip control, the acceleration continues even after 0.65 [S] when the slip occurs. Also, the tangential force F t As a result of anti-slip control, there is no decrease even after 0.65 [S] when slippage occurs.

[0077] 14A and 14B are diagrams showing simulation results of the slip acceleration command value and the slip velocity when the control according to the embodiment is used. S ref , Figure 14(B) shows the slip velocity v S 14(C) is an enlarged view of the range from 0.68 [S] to 0.73 [S] in FIG. 14(B). Slip acceleration command value v゜ S ref It can be seen that the sliding velocity v is almost constant throughout the entire operation. S After slippage occurs, the vehicle temporarily slows down, but then begins to accelerate again.

[0078] Next, an example of a simulation result in the case where the anti-slip control according to this embodiment is not used will be described with reference to FIGS. Fig. 15 is a diagram showing simulation results for the axial current, motor side speed, and torsional torque when the control according to the embodiment is not used. Fig. 15(A) shows the value of the axial current of the motor 31, Fig. 15(B) shows the motor side speed, and Fig. 15(C) shows the change over time when the horizontal axis is time [S].

[0079] Here, comparing the example shown in Fig. 15 with the example shown in Fig. 11, the shaft current of the motor 31 hardly flows when the anti-slip control is not used. Also, the motor side speed is also almost not rotating. Also, torsional torque is not generated.

[0080] 16A and 16B are diagrams showing simulation results of the slippage determination signal when the control according to the embodiment is not used. FIG. 16A and FIG. 16C show the change in the slippage determination signal over time. FIG. 16C shows the change in the drive wheel rotation speed v d Shows the change in. 15 and 11, the changes up to 0.65 [S] when slip occurs are similar. However, the changes after 0.65 [S] when slip occurs are different. Also, the driving wheel rotation speed v d It can be seen that there is almost no rotation.

[0081] FIG. 17 is a diagram showing simulation results of slip velocity, wheel speed, running speed, and tangential force when the control according to the embodiment is not used. S , FIG. 17(B) shows the speed v of the drive wheel 32. d , FIG. 17(C) shows the travel speed v L , Figure 17(D) shows the tangential force F t The time changes of are shown. Sliding velocity v S starts accelerating gradually from 0.2 [S] and continues accelerating. Also, the speed of the drive wheel 32 v d There is almost no change in the running speed of the transport vehicle 1 v L The acceleration is gradual. Also, the tangential force F t For , the force starts to increase gradually from 0.2 [S] and a constant force is applied.

[0082] [Summary of the embodiment] According to the embodiment described above, the transport vehicle control device 10 includes the rotational position information acquisition unit 111 to acquire rotational position information including information indicating the amount of rotation of the motor 31, and includes the state quantity observer 113 to acquire the torque τ S By providing the slip speed information acquisition unit 116, the slip speed v of the drive wheels 32 during a predetermined period is calculated. S The change in Δv S By providing a slip acceleration command generator 117, the torque τ due to the effect of resonance is S and the change in sliding speed Δv S Based on this, a slip acceleration command value v°, which is an acceleration for suppressing slip of the drive wheels 32, is calculated. S ref By providing the torque command generator 121, the motor 31 is supplied with a motor torque command value τ M ref Output.

[0083] Also, according to this embodiment, the traveling speed is estimated from the torque generated by the motor and the change in the rotation speed of the motor, and thus the wheel slip is detected and the torque generated by the motor is adjusted. Therefore, according to this embodiment, the wheel slip between the road surface and the wheels is detected by estimating the traveling speed, and the power assist amount is automatically controlled, so that wheel slip does not occur even on road surfaces other than paved roads where wheel slip is likely to occur. Therefore, according to this embodiment, even operators other than skilled operators can operate the manual transport vehicle.

[0084] In addition, according to the present embodiment, the transport vehicle control device 10 includes the slip acceleration regulator 114, so that the torque τ due to the influence of resonance calculated by the state quantity observer 113 can be reduced. S Based on this, the slip acceleration adjustment value v S The slip acceleration command generator 117 calculates a slip acceleration adjustment value v°' S Based on this, the slip acceleration command value v S ref Calculate. Therefore, according to this embodiment, the torque generated in the drive wheels 32 can be suitably controlled.

[0085] In addition, all or part of the functions of each unit of the transport vehicle 1 in the above-mentioned embodiment may be realized by recording a program for realizing these functions in a computer-readable recording medium, reading the program recorded in the recording medium into a computer system, and executing it. Note that the "computer system" here includes hardware such as an OS and peripheral devices.

[0086] In addition, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, and storage units such as hard disks built into computer systems. Furthermore, the term "computer-readable recording medium" may also include those that dynamically hold a program for a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, and those that hold a program for a certain period of time, such as a volatile memory inside a computer system that serves as a server or client in such cases. Furthermore, the above program may be one that realizes part of the above-mentioned functions, or may be one that can realize the above-mentioned functions in combination with a program already recorded in the computer system.

[0087] Although an embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. [Explanation of symbols]

[0088] 1...transport vehicle, 10...transport vehicle control device, 12...control system, 13...drive system, 21...loading platform, 22...handle, 23...control box, 31...motor, 32...drive wheel, 33...shaft, 34...pulley, 35...rubber tire, 36...belt, 111...rotational position information acquisition unit, 112...speed detector, 113...state quantity observer, 114...slip acceleration regulator, 115...torque reduction amount determiner, 116...slip speed information acquisition unit , 117...slip acceleration command generator, 118...running acceleration estimator, 119...slip acceleration controller, 120...torsion torque controller, 121...torque command generator, 9...anti-slip control device, 90...control system, 91...driving system, 92...speed detector, 93...disturbance observer, 94...torque reduction amount determiner, 95...slip acceleration command generator, 96...running acceleration estimator, 97...slip acceleration controller, 98...torque command generator

Claims

1. a rotational position information acquisition unit that acquires rotational position information including information indicating an amount of rotation of a motor in a two-inertia resonance system including a drive wheel and a motor that rotates and drives the drive wheel; a state quantity observer that calculates a torque due to an influence of resonance based on the rotational position information; a slip speed information acquisition unit that acquires a change in slip speed of the drive wheels over a predetermined period of time; a slip acceleration command generator that calculates a slip acceleration command value, which is an acceleration for suppressing slip of the drive wheels, based on the calculated torque due to the effect of resonance and the acquired amount of change in the slip speed during a predetermined period of time; a torque command generating unit that calculates a motor torque command value that is a command value of a torque to be applied to the motor based on the calculated slip acceleration command value; a torque command value output unit that outputs the generated motor torque command value to the motor; A transport vehicle control device comprising:

2. A slip acceleration adjustment unit is further provided which calculates a slip acceleration adjustment value based on the torque due to the effect of the resonance calculated by the state quantity observer, The slip acceleration command generating unit calculates the slip acceleration command value based on the calculated slip acceleration adjustment value. The transport vehicle control device according to claim 1 .

3. a torsional torque control unit that calculates a current command value of a current flowing through the motor based on the torque due to the effect of resonance calculated by the state quantity observer, a rotational speed of the motor based on the rotational position information, and the slip acceleration command value, The torque command generating unit calculates the motor torque command value based on the calculated current command value. The transport vehicle control device according to claim 1 or 2.

4. the state quantity observer further calculates an angular velocity estimation value, which is a value obtained by estimating each speed of the drive wheels, based on the rotational position information; a slip acceleration control unit that calculates a torsional torque command value based on the angular velocity estimation value calculated by the state quantity observer and the slip acceleration command value calculated by the slip acceleration command generation unit, The torsional torque control unit calculates the current command value based on the torsional torque command value. The transport vehicle control device according to claim 3 .

5. A transport vehicle control device according to any one of claims 1 to 4, The motor controlled by the transport vehicle control device; the drive wheel that is rotationally driven by the motor; A transport vehicle equipped with the above.

6. On the computer, a rotational position information acquisition step of acquiring rotational position information including information indicating an amount of rotation of a motor in a two-inertia resonance system including a drive wheel and a motor that drives and rotates the drive wheel; a state quantity observer execution step of calculating a torque due to an influence of resonance based on the rotational position information; a slip acceleration acquisition step of acquiring an amount of change in slip speed of the drive wheels over a predetermined period of time; a slip acceleration command generating step of calculating a slip acceleration command value, which is an acceleration for suppressing slip of the drive wheels, based on the calculated torque due to the effect of resonance and the acquired amount of change in the slip speed during a predetermined period of time; a torque command generating step of calculating a motor torque command value which is a command value of a torque to be applied to the motor based on the calculated slip acceleration command value; a torque command value output step of outputting the generated motor torque command value to the motor; A program that executes the following.

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