JP7261241B2 - automatic steering controller - Google Patents

Description

Embodiments of the present invention relate to automatic steering of work vehicles.

2. Description of the Related Art Conventionally, for the purpose of improving the efficiency of agricultural work, automatic steering control has been performed in which work vehicles such as tractors and rice transplanters follow a designated travel route. According to this automatic steering control, the steering of the work vehicle is controlled so as to position the work vehicle on the travel route based on the separation distance between the target position on the travel route and the position of the work vehicle.

In addition, as technology related to automatic steering of work vehicles, there are a steering member for steering the body, a position information acquisition device for acquiring the position coordinates of the body, an automatic straightening device for operating the steering member to make the body travel straight, and a body. A work vehicle equipped with a control device for controlling each part is provided with a reference position acquisition member for acquiring a reference position that is a reference for straight traveling of the machine body, and an on/off member for turning on and off the automatic straight traveling device, and the control device controls the reference position. There is known a work vehicle characterized by activating an automatic straight-ahead device by operating an on/off member in a state in which is acquired (see, for example, Patent Document 1).

JP 2018-97621 A

Compared to the paved roads on which general vehicles travel, the fields on which work vehicles travel have a wide range of characteristics depending on the field. The steering characteristics of the rice transplanter differ from paddy field to paddy field due to various factors such as the water level from the ground to the surface of the water. Therefore, when the expected characteristics of the field differ greatly from the actual characteristics of the field, there is a problem that the optimum automatic steering according to the field is not performed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic steering control system that can automatically steer a work vehicle optimally for a field.

In order to solve the above-described problems, the automatic steering control device of the present embodiment is an automatic steering control device that outputs a steering signal to a work vehicle that is a target of automatic steering, and the work vehicle that is detected as a target travel direction is A steering calculation unit having a first parameter set including a plurality of values to be given to a proportional gain in the PID control, and a plurality of the first parameter sets included in the first parameter set. and a presentation unit that presents alternatively selectable options, and an acquisition unit that acquires the option selected for the first parameter set, wherein the steering calculation unit provides the first parameter set with The PID control is performed by setting the value indicated by the acquired option as the proportional gain.

According to the present invention, it is possible to perform automatic steering of a working vehicle that is optimal for a field.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic side view which shows the structure of the agricultural tractor which concerns on embodiment. 1 is a block diagram showing the hardware configuration of an automatic steering system according to an embodiment; FIG. 2 is a block diagram showing the hardware configuration of an automatic steering control device; FIG. 2 is a block diagram showing the functional configuration of an automatic steering control device; FIG. 2 is a block diagram showing a control configuration of an automatic steering control system; FIG. FIG. 3 is a block diagram showing a control configuration of a steering calculation unit; FIG. FIG. 11 is a schematic diagram showing a user interface for setting the control amount;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of target vehicle and automatic steering system)
First, an automatic steering system according to the present embodiment and a target vehicle automatically steered by this automatic steering system will be described. FIG. 1 is a schematic side view showing the configuration of an agricultural tractor according to an embodiment. FIG. 2 is a block diagram showing the configuration of the automatic steering system according to the embodiment.

A vehicle to be steered by the automatic steering system according to the present embodiment is a working vehicle, specifically, an agricultural tractor 1 as shown in FIG. The tractor 1 is a four-wheeled vehicle having a vehicle body 10, two front wheels 11 and two rear wheels 12, but may be any vehicle as long as it can be steered. Alternatively, it may be a rail vehicle with crawlers. The tractor 1 also includes a seat 13 for a driver to sit on, a link mechanism 14 for connecting and connecting a work machine (not shown), a steering column 15, a steering handle 16, a steering drive device 17, pedals 18 including an accelerator, a brake, and the like. A roof portion 19 is provided.

A steering system for steering the tractor 1 by giving a deflection angle to the front wheels 11 is provided in the steering column 15, and an input shaft 151 for inputting a steering wheel angle from the steering wheel 16 or the steering drive device 17 to the steering system is incorporated. , a steering angle based on the rotation of the input shaft 151 is given to the front wheels 11 . The steering drive device 17 is a device retrofitted to automatically steer the tractor 1, which is assumed to be manually steered and does not have a structure for automatic steering control. In addition, the upper end of the input shaft 151 of the steering system is fitted below. The roof portion 19 is a substantially flat member as a whole that is mounted on four support frames provided at different positions on the front, rear, left, and right sides of the vehicle body 10 .

Sensors 21 including at least a GNSS (Global Navigation Satellite System) and a gyro sensor are provided on the upper surface of the roof portion 19 . The sensors 21 may include any sensors as long as they detect at least the position of the vehicle and the direction of the vehicle on the running surface. In addition, an automatic steering control device 22 is provided on one of the support frames that support the roof portion 19, which is located in front. The automatic steering control device 22 controls the automatic steering of the tractor 1, and as will be described in detail later, presents the situation regarding the automatic steering control to the driver of the tractor 1, and also provides the driver with the automatic steering control. Since it acquires the operation, it is desirable to be provided so as to be positioned in front of the driver.

As shown in FIG. 2, the automatic steering system includes a steering drive device 17 that drives an input shaft 151 in the steering system, sensors 21, an automatic steering control device 22, and a steering wheel angle control device 23 (not shown in FIG. 1). Consists of

The steering drive device 17 includes a transmission shaft 171 that transmits driving force to the input shaft 151, a motor 172 that is a stepping motor that drives the transmission shaft 171, and an encoder 173 that is a rotary encoder that detects the rotation amount and rotation position of the transmission shaft 171. Prepare. Note that the motor 172 may be any type of motor as long as it can output torque sufficient to rotate the input shaft 151 .

The automatic steering control device 22 outputs steering signals based on the values detected by the sensors 21, and the steering wheel angle control device 23 feedback-controls the steering drive device 17 based on the steering signals instructed by the automatic steering control device 22. do. Here, the steering driving device 17 drives the transmission shaft 171 by controlling the motor 172 so that the rotational position detected by the encoder 173 becomes a desired rotational position.

In this way, the tractor 1 configured to be manually steered by retrofitting the steering drive device 17, the sensors 21, the automatic steering control device 22, and the steering wheel angle control device 23 to the tractor 1 Automatic steering can be realized.

(Configuration of automatic steering control device)
The hardware configuration and functional configuration of the automatic steering control device will be described. 3 and 4 are block diagrams showing the hardware configuration and functional configuration of the automatic steering control device, respectively.

The automatic steering control device 22 includes, as hardware, a CPU (Central Processing Unit) 221, a RAM (Random Access Memory) 222, a storage device 223, an input/output I/F (Interface) 224, and a touch panel 225, as shown in FIG. , switch group 226 .

The CPU 221 and RAM 222 cooperate to execute various functions described later, and the storage device 223 stores various data used for processing executed by the various functions. The touch panel 225 is an input/output device having a display as an output device and a touch sensor as an input device. The switch group 226 is a plurality of switches used as an input device for selecting options to be described later, and each switch is configured as a slide switch or a dip switch, for example. The input/output I/F 224 performs data input/output with the touch panel 225 as an input/output device. Both the input device and the output device in the automatic steering control device 22 may be of any type.

Further, the automatic steering control device 22 includes, as functions, a route setting unit 31, a steering control unit 32, a presentation unit 33, and an acquisition unit 34, as shown in FIG. The route setting unit 31 sets a target travel route, which will be described later, based on an instruction from the driver via the touch panel 225 . The steering control section 32 controls automatic steering of the tractor 1 based on the target travel route set by the route setting section 31 . The presentation unit 33 presents information regarding automatic steering by the steering control unit 32 to the driver via the touch panel 225 . The acquisition unit 34 acquires the driver's operation regarding the automatic steering setting by the steering control unit 32 via the touch panel 225 .

(Control configuration of automatic steering control system)
A control configuration of the automatic steering control system will be described. FIG. 5 is a block diagram showing the control configuration of the automatic steering control system. FIG. 6 is a block diagram showing the control configuration of the steering calculation section.

As shown in FIG. 5 , the steering control section 32 has a target traveling direction calculation section 321 and a steering calculation section 322 . The target travel direction calculation unit 321 matches the vehicle position with the target travel route based on the vehicle position, which is the position of the tractor 1 detected by the sensors 21, and the target travel route set by the route setting unit 31. A target traveling azimuth, which is the traveling azimuth of the tractor 1, is calculated and output. The steering calculation unit 322 is based on the traveling direction deviation, which is the difference between the target traveling direction output by the target traveling direction calculating unit 321 and the traveling direction of the tractor 1 detected by the sensors 21, in this embodiment. It calculates and outputs a steering signal indicating the steering angle.

The steering wheel angle control device 23 controls the input shaft 151 by outputting to the steering drive device 17 a steering wheel angle based on the steering angle indicated by the steering signal output from the steering calculation unit 322 , and controls the input shaft 151 based on the rotation of the input shaft 151 . A steering angle is given to the front wheels 11 to control the traveling direction of the tractor 1 , and sensors 21 detect the vehicle position and traveling direction of the controlled tractor 1 .

As shown in FIG. 6, the steering calculation unit 322 performs PID control for outputting a steering angle based on the heading deviation. In this embodiment, the integral time constant T _i and the differential time constant T _d are set according to the characteristics of the tractor 1 .

The proportional element is set according to the field. As will be described later, for the proportional element, a plurality of values of the proportional gain K _p are prepared in advance as a first parameter set, and the value of the proportional gain K _p can be set by the driver as the control amount level.

In addition, the integral time constant T _i and the differential time constant T _d have at least one value of the integral time constant T _i and the differential time constant T _d , and are based on the characteristics of the vehicle type and associated with the vehicle type. A second parameter set having a plurality of parameters is prepared in advance, and the driver can set at least one value of the integral time constant T _i and the differential time constant T _d as a control parameter for a specific vehicle type. Here, the type of vehicle specifically indicates a type of work vehicle classified by type, manufacturer, model, etc. For example, it is a category in which vehicles having the same configuration are classified so as to belong to the same category. . The parameter included in the second parameter may be a category obtained by classifying work vehicles according to a predetermined criterion. It may be associated with any category of types. Examples of types of work vehicles include tractors, rice transplanters, combine harvesters, vegetable transplanters, agricultural chemical spray vehicles, vegetable harvesters, lawn mowers, and the like. Examples of types of work machines include cultivators, front loaders, rakes, balers, mowers, subsoilers, harrows, plows, and slurry tankers. Types of tires include soft soil, hard soil, upland, grassland, muddy land, sandy soil, lawn, paddy field, dry field, wet field, shallow field, deep field, etc. mentioned. Further, the parameters included in the second parameter may be associated with at least two combinations of the vehicle type of the work vehicle, the type of the work vehicle, the type of work equipment attached to the work vehicle, and the type of tires of the work vehicle. good.

(Control amount setting)
The setting of the control amount will be explained. FIG. 7 is a schematic diagram showing a user interface for control amount setting.

As shown in FIG. 7, the presentation unit 33 uses the first parameter set for the proportional gain _Kp as the control amount, and the second parameter set for at least one of the integral time constant T _i and the differential time constant _Td . is displayed on the touch panel 225 as the vehicle type name so that it can be selected by the driver or the operator. Here, the operator means a person who equips the tractor 1 with the automatic steering control system. The presentation unit 33 displays a plurality of levels arranged in descending order of level in the level display area L, and displays a plurality of vehicle model names in the vehicle model display area V. FIG. Each of the plurality of values included in the first parameter set is associated with each of a plurality of levels indicating the relative magnitude of each value in the first parameter set in stages, and larger values correspond to larger levels. Attached. Also, each of the plurality of parameters included in the second parameter set is associated with the vehicle model name of the work vehicle based on each parameter. The presentation unit 33 presents such multiple levels and multiple vehicle model names to the driver or operator in a selectable manner.

In addition, the presentation unit 33 emphasizes and displays only the level being selected, that is, the level associated with the value applied to the current proportional gain _Kp on the touch panel 225, and also displays the current integral time constant T Only the vehicle model name associated with the parameter applied to _i and the differential time constant _Td is highlighted and displayed on the touch panel 225 . Each of the plurality of values in the first parameter set and each of the plurality of parameters in the second parameter set may be presented as options that can be selected by the driver.

The acquisition unit 34 acquires the level selected by the driver through a tap operation from among the plurality of levels displayed on the touch panel 225 by the presentation unit 33 . The steering calculation unit 322 sets the proportional gain _Kp to a value associated with the level acquired by the acquisition unit 34 in the parameter set.

Thus, by presenting the value of the proportional gain _Kp as a selectable level and setting the proportional gain _Kp to a value corresponding to the selected level, the driver does not need to have specialized knowledge. It is possible to intuitively select the value of the proportional gain K _p , and for example, by selecting a stronger level for an agricultural field where the resistance to the front wheels 11 in steering becomes stronger, an automatic steering system that is more suitable for the agricultural field can be obtained. Steering control can be performed.

It should be noted that presentation of multiple levels and multiple vehicle model names by the presentation unit 33 may be performed using any means other than display on the touch panel 225. Examples of presentation means include sound, light emission, and vibration. and depends on the output device mounted on the tractor 1. Similarly, the selection of the level acquired by the acquisition unit 34 may be made using any means other than the touch operation on the touch panel 225. Examples of selection means include voice recognition, physical buttons, and the like. It depends on the input device installed in the . In this embodiment, it is also possible to use the switch group 226 as the presentation means and the selection means. When each switch group 226 is a DIP switch, a plurality of levels and a plurality of vehicle types are presented by combining the plurality of operation sections.

Also, the first parameter set may be prepared in association with each of the plurality of parameters in the second parameter set. In this case, the control calculation unit 322 has a plurality of first parameter sets and second parameter sets, and the presentation unit 33 can select the first parameter set associated with the parameter selected in the second parameter Present.

Examples of working vehicles to be controlled by the automatic steering control system include agricultural vehicles such as tractors, rice transplanters, combine harvesters, vegetable transplanters, agricultural chemical spray vehicles, vegetable harvesters, and lawn mowers. , the automatic steering control system can control all work vehicles that perform work along a predetermined route.

Embodiments of the invention are provided by way of example and are not intended to limit the scope of the invention. This novel embodiment can be embodied in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.

1 tractor (work vehicle)
22 Automatic steering control device 33 Presentation unit 34 Acquisition unit 321 Target traveling direction calculation unit 322 Steering calculation unit

Claims (11)

An automatic steering control device that outputs a steering signal to a work vehicle that is a target of automatic steering,
a steering calculation unit that outputs the steering signal by PID control based on a target traveling direction and the detected traveling direction of the work vehicle, and has a first parameter set including a plurality of values to be given to a proportional gain in the PID control; ,
a presentation unit that indicates a plurality of values included in the first parameter set and presents alternatives that can be selected;
an acquisition unit that acquires an option selected for the first parameter set;
The automatic steering control device, wherein the steering calculation unit performs the PID control by setting the proportional gain to a value indicated by the option acquired for the first parameter set. Each of the plurality of values included in the first parameter set is associated with each of a plurality of levels indicating the relative magnitude of the value in the first parameter set in stages,
The presentation unit selectably presents the plurality of levels as options for the first parameter set,
The acquisition unit acquires the selected level,
2. The automatic steering control system according to claim 1, wherein the steering calculation unit sets the proportional gain to a value corresponding to the selected level in the first parameter set. 3. The work vehicle according to claim 1, further comprising a target travel direction calculation unit that outputs the target travel direction based on a preset target travel route and the detected position of the work vehicle. Automatic steering controller. At least one of the time constant of the integral element and the time constant of the differential element in the PID control is set based on the characteristics of the work vehicle. 3. An automatic steering control device according to claim 1. The steering calculation unit has a second parameter set including a plurality of parameters each having a value to be given to at least one of the time constant of the integral element and the time constant of the differential element,
The presentation unit presents a plurality of parameters included in the second parameter set and presents options that can be selected alternatively,
The acquisition unit acquires options selected for the second parameter set,
The steering calculation unit performs the PID control by setting the parameter indicated by the option acquired for the second parameter set to at least one of the time constant of the integral element and the time constant of the differential element. The automatic steering control device according to claim 4, characterized by: The steering calculation unit has a plurality of first parameter sets associated with each of the plurality of parameters included in the second parameter set,
The presentation unit presents a plurality of values included in the first parameter set associated with the parameter indicated by the option selected for the second parameter set, and presents alternatively selectable options. 6. The automatic steering control device according to claim 5. Each of the plurality of parameters included in the second parameter set is associated with a category of work vehicle based on which the parameter is based;
The presentation unit acquires the category of the selected work vehicle,
The steering calculation unit sets a parameter corresponding to the selected work vehicle category in the second parameter set to either the time constant of the integral element or the time constant of the differential element. 7. The automatic steering control system of claim 6. The category of the work vehicle is a category classified by at least one of the type of work vehicle, the type of work vehicle, the type of work equipment attached to the work vehicle, and the type of tires of the work vehicle. The automatic steering control device according to claim 7, characterized by: The automatic steering control device according to any one of claims 1 to 8, wherein the presentation unit displays the options on a display. 10. The automatic steering control device according to claim 9, wherein the acquisition unit acquires the selected option by operating a touch sensor. The automatic steering control device according to any one of claims 1 to 10, wherein the acquisition unit acquires the selected option by operating a switch.

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