JP2020002708A - Work machine - Google Patents

Abstract

To provide a work machine calculating a relative angle of an upper revolving body and a lower traveling body from GNSS information.SOLUTION: A work machine comprises: a crawler-type lower traveling body 3; a positioning terminal 15 calculating positions of first and second antennae 13, 14 on an upper revolving body 2; and a controller 16 calculating a relative angle α between the upper revolving body and the lower traveling body. The controller comprises: a vehicle body angle calculating portion A03 calculating an angle θ1 of the upper revolving body 2 at a time t1; a traveling displacement angle calculating portion A05 calculating a traveling displacement angle φ formed by a straight line passing a position of the first antenna at times t1, t2; a deviation angle calculating portion A06 calculating a deviation angle δφ that is a difference between an angle φ' formed by the lower traveling body 3 and the traveling displacement angle φ at the time t1 on the basis of positions of the first and second antennae at the times t1, t2; a traveling displacement angle correction portion A07 correcting the traveling displacement angle φ at the deviation angle δφ; and a relative angle calculating portion A08 calculating the relative angle α at the time t1 on the basis of a corrected traveling displacement angle φ' and the angle θ1.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a working machine including an upper swing body and a lower traveling body such as a hydraulic shovel.

  In recent years, in response to information-oriented construction, a machine that displays the position and orientation of a working device (front working device) that is constructed by connecting a plurality of front members such as a boom, an arm, and a bucket to a working machine. Some machines have a function of guidance and a machine control function for controlling the position of a working device to move along a target construction surface. As a typical example, the position of the bucket tip and the bucket angle of the excavator are displayed on a monitor, and when the bucket tip approaches the target construction surface, the operation of the working device is performed so that the bucket tip does not enter below the target construction surface. It is known to place restrictions on the size.

  In this type of information processing-compatible work machine, an inertial measurement unit (IMU: Inertia Measurement Unit) may be used as a sensor for detecting the attitude of each front member and the attitude of the upper swing body.

  As this type of information processing-compatible work machine, there is a work machine provided with two satellite positioning systems, a so-called GNSS (Global Navigation Satellite System) antenna, on an upper revolving unit. Using the positioning result of each GNSS antenna, the direction (azimuth) of the upper swing body can be calculated, and thereby the direction (azimuth) of the working device can be calculated. This configuration has a GNSS antenna on the upper revolving unit, so it is a suitable configuration for the problem of performing the “excavation operation by matching the orientation of the working device (upper revolving unit) to a specific plane”. It can be said.

  However, since the GNSS antenna is provided on the upper revolving unit, the orientation of the lower traveling unit cannot be determined from the GNSS positioning result. In other words, "a posture in which only the upper revolving structure is rotating without the lower traveling structure rotating" (see FIG. 17A) and a "posture in which only the lower traveling structure is rotating and the upper revolving structure is not rotating" ( 17b), the orientations of the working devices are the same, so that referring to only the positioning result by GNSS, these two postures are regarded as the same posture. However, these two positions are clearly different positions.

  As an example of the inconvenience caused by not knowing the orientation of the undercarriage, a case where a large work surface is constructed will be considered. If the undercarriage is also directly facing the work surface as shown in FIG. 18a, the undercarriage must be re-oriented once after the excavation work and moved, and after the movement, the working device must be again faced with the work surface. become. On the other hand, as shown in FIG. 18b, when the lower traveling body is in a horizontal state with respect to the work surface, the work device always faces the work surface even when traveling, so that the position as in FIG. The alignment operation is not required, and work efficiency can be improved. When performing such work, not only the direction of the upper revolving structure but also the direction of the lower traveling structure becomes important. However, as described above, it is not easy to know the orientation of the undercarriage only from the GNSS positioning results.

  To solve such a problem, Patent Document 1 discloses a swivel joint provided with a rotation angle sensor capable of detecting a turning angle of an upper turning body.

  If the orientation of the upper revolving unit is detected by the two GNSSs and the relative angle between the upper revolving unit and the lower traveling unit is detected by the rotation angle sensor of Patent Document 1, the orientation of the lower traveling unit can be calculated immediately. it is conceivable that. Further, if a turning angle sensor is provided on the turning rotary shaft as in Patent Document 1, it is possible to accurately detect the relative angle between the upper revolving unit and the lower traveling unit without being affected by mechanical play or mounting errors. It is.

  However, with such a configuration, since the rotation angle sensor must be mounted on the rotation axis, it is extremely difficult to repair or replace the sensor when the rotation angle sensor fails. Also, if a sensor failure occurs in a mountainous area where it is difficult to carry in repair equipment such as a mobile crane, repair and replacement cannot be performed, and there is a possibility that the process at the construction site may be delayed.

  In order to solve such a problem, in Patent Document 2, without attaching a sensor to the swing axis, the lower traveling body with respect to the upper swing body is changed with respect to the upper swing body based on a change in the horizontal component in the positioning result of the GNSS attached to the upper swing body. A method for calculating a posture has been proposed.

JP-A-2017-82494 JP 2006-214236 A

  Patent Literature 2 does not disclose specific contents of “change in horizontal component”. However, those skilled in the art will consider calculating the relative angle between the upper revolving unit and the lower traveling unit by, for example, the following calculation method.

<Calculation example>
First, the GNSS positioning result is converted into rectangular coordinates of a specific geodetic system (for example, world geodetic system) to obtain x, y, and z coordinates of the GNSS antenna position. Using this coordinate system, consider the case where only the lower traveling body is driven (forward, backward) without rotating the upper rotating body.

  Here, as shown in FIG. 19, when “the change in the horizontal direction” is regarded as a combination of the change in the change amount Δx in the x coordinate and the change in the change amount Δy in the y coordinate, the “horizontal change” Is equal to the direction of travel. Then, assuming that the moving direction of the shovel is equal to the angle θrn of the undercarriage, the angle θrn of the undercarriage can be calculated by the following equation (1).

  According to the above calculation method, it can be said that the angle of the undercarriage can be calculated without providing an angle sensor on the turning axis. Note that in FIG. 19, the x-axis is set to θrn = 0 degrees for ease of description, but it should be noted that embodiments of the present invention described below are not limited to “set the x-axis to 0 degrees”. It should be noted that the following figures also emphasize the ease of explanation, and that the angles are not necessarily set in accordance with FIG. (<Calculation example> end)

  However, in the case of a hydraulic excavator having a crawler-type lower traveling body, even if the excavator is to be run straight (for example, parallel to the x-axis in FIG. 19), the hydraulic excavator may be slipped due to a road surface or a pressure difference of a traveling hydraulic motor. Meanders. That is, even if the lower vehicle is operated so as to run straight, the angle of the lower vehicle changes before and after traveling. (In this paper, the difference between the angles of the lower vehicle before and after traveling is referred to as the "deviation angle." "). That is, the assumption that the moving direction of the shovel is equal to the angle θrn of the undercarriage does not hold. For this reason, it is not possible to accurately calculate the angle of the undercarriage by simply using equation (1). Patent Document 2 does not show a solution to this problem.

  In addition, it is known that an error of about ± 2 cm occurs in positioning using GNSS even when using RTK (Real Time Kinematics), which is a highly accurate positioning method using correction data.

  Here, taking the case where the angle θrn of the lower traveling body is 0 ° as an example, consider the influence of this positioning error on the above-mentioned equation (1). As described above, Patent Literature 2 makes no reference to “horizontal change”, but a difference between positioning results for each sampling cycle (for example, 1 second) of a general positioning system will be referred to as “horizontal change”. Further, since the maximum speed of the traveling operation of a general hydraulic excavator (for example, a vehicle weight of 20t class) is about 5 km / h, the vehicle moves forward by about 1.4 m (140 cm) in one cycle (one second). Here, assuming that the errors in the y direction before and after the movement are -2 cm and +2 cm, respectively, the angle calculated by Expression (1) is approximately 1.6 degrees from Expression (2).

  As can be seen from equation (2), the influence of the positioning error (numerator of the arc tangent function) is suppressed as the moving distance becomes longer (as the absolute value of the denominator of the arc tangent function becomes larger). This principle is as shown in FIGS. 20a and 20b, and the effect of the error is relatively smaller in FIG. 20b with a longer moving distance than in FIG. 20a with a shorter moving distance. Therefore, in order to reduce the influence of the positioning error of the GNSS, it is conceivable to extend the moving distance.

  However, the above discussion is limited to the case where RTK positioning is correctly performed (in the case of the FIX solution), and in the case of the Float solution where RTK positioning is not successful, the positioning error (the absolute value of the numerator of the arctangent function) ) Becomes large (for example, about ± 20 cm), and the traveling angle θrn calculated by the equation (2) greatly changes. Patent Document 2 does not mention this problem at all.

  Therefore, it is not easy for those skilled in the art to accurately calculate the angle of the undercarriage using the GNSS positioning result in an actual hydraulic excavator.

  The present invention has been made in view of the problem of Patent Document 2 described above, and has as its object to use an existing sensor configuration provided in a working machine for computerized construction, that is, information obtained from the GNSS to turn the upper part. An object of the present invention is to provide a work machine capable of calculating a relative angle between a body and a lower traveling body.

  The present application includes a plurality of means for solving the above problems. For example, a crawler-type lower traveling body, an upper revolving body rotatably mounted on an upper portion of the lower traveling body, and an upper revolving body. A first antenna and a second antenna attached to a revolving superstructure, a positioning terminal for calculating positions of the first antenna and the second antenna, respectively, and a controller for calculating a relative angle between the upper revolving superstructure and the lower traveling structure And the position of the first antenna and the second antenna calculated by the positioning terminal at a first time and the traveling operation of the lower traveling body after the first time. A storage device for storing the positions of the first antenna and the second antenna calculated by the positioning terminal at a second time after performing the operation, and at the first time A vehicle body angle calculation unit configured to calculate a first vehicle body angle which is an angle of the upper revolving structure at the first time from the positions of the first antenna and the second antenna; and a vehicle body angle calculation unit configured to calculate the first vehicle angle at the first time and the second time. A travel displacement angle calculation unit that calculates a travel displacement angle that is an angle between a straight line passing through the position of the first antenna at the first time and the second time and a predetermined reference line, based on the position of the one antenna; Based on the positions of the first antenna and the second antenna at the first time and the second time, the difference between the angle formed by the lower traveling body with the reference line and the travel displacement angle at the first time is determined. A travel angle calculating section for calculating a certain travel angle, a travel displacement angle correction section for adding the travel angle to the travel displacement angle to correct the travel displacement angle, and a travel displacement angle correction section. And a relative angle calculation unit, wherein calculating a relative angle of the lower traveling body and the upper rotating body at the first time based and the traveling displacement angle that Tadashisa in the first vehicle body angle.

  According to the present invention, the relative angle between the upper turning body and the lower traveling body can be calculated from the positioning result of the GNSS. Unlike a configuration in which a rotation axis is provided with a rotation angle sensor, the GNSS has an advantage that even if a failure occurs, replacement and repair are very simple.

1 is a perspective view of a hydraulic shovel according to an embodiment of the present invention. It is a side view of the hydraulic shovel concerning an embodiment of the present invention. It is a functional block diagram of a controller concerning a 1st embodiment. It is a schematic diagram explaining the contents of a calculation of an upper revolving superstructure angle calculation part of a 1st embodiment. FIG. 5 is a schematic diagram illustrating the calculation content of a front attitude calculation unit according to the first embodiment. It is a functional block diagram of a relative angle calculation part of a 1st embodiment. 5 is an example of a time chart when performing a calculation by a relative angle calculation unit. FIG. 6 is a diagram schematically illustrating the calculation contents of a relative angle calculation unit. FIG. 6 is a diagram schematically illustrating the calculation contents of a relative angle calculation unit. It is a schematic diagram showing a coordinate change of the GNSS antenna when the undercarriage slides. It is a schematic diagram explaining an example of the calculation content of a deviation angle. It is a schematic diagram explaining an example of the calculation content of a deviation angle. It is a schematic diagram explaining an example of the calculation content of a deviation angle. It is a schematic diagram explaining an example of the calculation content of a deviation angle. It is a functional block diagram of a relative angle calculation part of a 2nd embodiment. It is a functional block diagram of a relative angle calculation part of a 3rd embodiment. It is a schematic diagram explaining the calculation content of the running displacement angle calculation unit when the turning operation is performed. It is an example of the flowchart of the controller of the third embodiment. It is a schematic diagram which shows the subject of azimuth calculation using GNSS. It is a schematic diagram which shows the subject of azimuth calculation using GNSS. It is a schematic diagram which shows the procedure of an efficient slope work. It is a schematic diagram which shows the procedure of an efficient slope work. FIG. 5 is a schematic diagram illustrating a method of calculating an azimuth angle using GNSS. It is a schematic diagram explaining the influence which the positioning error of GNSS has on angle calculation. It is a schematic diagram explaining the influence which the positioning error of GNSS has on angle calculation. FIG. 7 is a diagram for explaining the relationship between a deviation angle δφ and its calculated values θc and θd.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a hydraulic excavator having a bucket as a working tool at the tip of a front device (front working device) will be described as an example of a working machine.

  FIG. 1 is a diagram schematically illustrating an external appearance of a hydraulic shovel, which is an example of a work machine according to the present embodiment. In FIG. 1, a hydraulic excavator 100 is a multi-joint type front device (front work) configured by connecting a plurality of front members (boom 4, arm 5, bucket (work implement) 6) that rotate vertically. 1) and an upper revolving unit 2 and a lower traveling unit 3 constituting a vehicle body. The upper revolving unit 2 is attached to the upper part of the lower traveling unit 3 so as to be pivotable. The lower traveling body 3 is a crawler traveling body, and is also called an endless track.

  The base end of the boom 4 of the front device 1 is supported on the front part of the upper swing body 2 so as to be rotatable in the vertical direction, and one end of the arm 5 is perpendicular to an end (distal end) different from the base end of the boom 4. A bucket 6 is supported on the other end of the arm 5 so as to be rotatable in the vertical direction. The boom 4, the arm 5, the bucket 6, the upper swing body 2, and the lower traveling body 3 include a boom cylinder 4 a, an arm cylinder 5 a, a bucket cylinder 6 a, a swing motor 2 a, and left and right traveling motors 3 a (which are hydraulic actuators). Only one traveling motor is shown).

  The boom 4, the arm 5, and the bucket 6 operate on a plane including the front device 1, and this plane may be hereinafter referred to as an operation plane. That is, the operating plane is a plane orthogonal to the rotation axis of the boom 4, the arm 5, and the bucket 6, and can be set at the center of the boom 4, the arm 5, and the bucket 6 in the width direction.

  An operation signal for operating the hydraulic actuators 2a to 6a based on an operation input from the operator, that is, the front device 1, the upper revolving unit 2, and the lower traveling unit 3 Are provided with operation levers (operation devices) 9a, 9b, 9c, 9d for outputting operation signals for operating the.

  The operation levers 9a and 9b can be tilted forward and backward and left and right, respectively, and the operations of the hydraulic actuators 2a, 4a, 5a and 6a are assigned to the front and rear directions or the left and right directions of the operation levers 9a and 9b, respectively. On the other hand, the operation levers (travel levers) 9c and 9 can be tilted in the front-rear direction, respectively. The front and rear of the operation lever 9c are assigned to the forward and backward movement of the left traveling motor 3, and the front and rear of the operation lever 9d are the right traveling. It is assigned to forward and backward movement of the motor 3. The operation levers 9a, 9b, 9c, 9d each include a sensor (not shown) for electrically detecting the tilt direction and the tilt amount of the lever, that is, the lever operation direction and the operation amount. The lever operation direction and the operation amount are output as operation signals to the controller 16 as a control device via electric wiring.

  Hereinafter, an operator such as a sensor for detecting a lever operation direction and an operation amount of these operation levers 9a, 9b, 9c, and 9d, and a sensor for detecting an operator's operation content on an input device such as a console panel installed in the cab 9 is provided. Is generically referred to as an operation detecting device C05.

  The operation control of the boom cylinder 4a, the arm cylinder 5a, the bucket cylinder 6a, the turning motor 2a, and the left and right traveling motors 3a is supplied to each of the hydraulic actuators 2a to 6a from a hydraulic pump device 7 driven by a prime mover such as an engine or an electric motor. The control valve 8 controls the direction and flow rate of the operating oil to be performed. The control valve 8 is controlled by a drive signal (pilot pressure) output from a pilot pump (not shown) via an electromagnetic proportional valve. The operation of each of the hydraulic actuators 2a to 6a is controlled by controlling the electromagnetic proportional valve by the controller 16 based on operation signals from the operation levers 9a and 9b.

  The operating levers 9a, 9b, 9c, 9d may be of a hydraulic pilot type, and the pilot pressure according to the operating direction and the operating amount of each of the operating levers 9a, 9b, 9c, 9d operated by the operator is controlled by a control valve. 8 as a drive signal to drive each of the hydraulic actuators 2a to 6a.

  The upper revolving unit 2 includes an inertial measurement unit (IMU) 12 which is an attitude sensor for detecting an inclination angle of the upper revolving unit 2 with respect to a predetermined plane (for example, a horizontal plane), and two GNSS antennas 13 shown in FIG. 14 are attached.

  The inertial measurement device 12 measures an angular velocity and an acceleration. For example, considering the case where the upper revolving unit 2 to which the inertial measurement device 12 is attached is stationary, the direction of the gravitational acceleration in the IMU coordinate system set in the inertial measurement device 12 (that is, the vertically downward direction) and the inertia measurement The inclination (pitch angle) of the upper swing body 2 in the front-rear direction can be detected based on the mounting state of the device 12 (that is, the relative positional relationship between the inertial measurement device 12 and the upper swing body 2). .

  One of a potentiometer, an inertial measuring device, and a cylinder stroke sensor is installed at an appropriate position as an attitude sensor for measuring the attitude of each of the boom 4, arm 5, and bucket 6, which are components of the front device 1. I have. Hereinafter, the sensors that measure and calculate the attitude of the front device 1 are collectively referred to as an attitude measuring device C02.

  FIG. 2 is a schematic view of the hydraulic excavator 100 of FIG. 1 as viewed from the side. As shown in FIG. 2, two GNSS antennas 13 and 14 are mounted on the upper swing body 2. For convenience of description, the GNSS antenna 13 may be referred to as a main antenna (first antenna), and the GNSS antenna 14 may be referred to as a sub-antenna (second antenna).

  On the basis of satellite signals (preferably signals from four or more satellites) received by the GNSS antennas 13 and 14, respectively, a positioning terminal (position measurement device) 15 mounted in the cab 9 or the structure of the upper swing body 2 Performs positioning calculation of the two antennas 13 and 14. The positioning terminal 15 includes a processing device (for example, a CPU) and a storage device in which a program for the processing device to measure the positions of the two antennas 13 and 14 from satellite signals received by the two antennas 13 and 14 is stored. It is a controller for positioning. The positioning terminal 15 outputs the positioning results of the two antennas 13 and 14 in the NMEA format including the latitude, longitude and geoid height of the respective GNSS antennas 13 and 14. One positioning terminal may perform positioning of two antenna positions, or a positioning terminal may be provided for each antenna. Hereinafter, for simplicity, a positioning system including the two GNSS antennas 13 and 14 and the positioning terminal 15 is collectively referred to as a position measuring device C01.

  A controller 16 is arranged in the structure of the operator's cab 9 or the upper revolving superstructure 2 similarly to the positioning terminal 15. The controller 16 includes a processing device (for example, a CPU) and a storage device (for example, a semiconductor memory such as a ROM or a RAM) in which a program executed by the processing device is stored. The controller 16 of the present embodiment receives signals from various sensors (the inertial measurement device 12, the attitude measurement device C02, and the operation detection device C05) and the positioning terminal 15 in the position measurement device C01, and performs various calculations regarding the operation of the shovel 100. Is going.

  FIG. 3 is a functional block diagram schematically showing the processing functions of the controller 16 according to the embodiment of the present invention. The controller 16 receives the results detected by the position measuring device C01 including the GNSS antennas 13 and 14, and the positioning terminal 15, the inertial measuring device 12, the attitude measuring device C02, and the operation detecting device C05. Based on these information, the controller 16 provides a machine guidance function for displaying an instruction on a display device C03 such as a display provided in the cab 9 and a control valve 8 and various control devices for controlling the movement of the front device 1. A machine control function for controlling a hydraulic control device C04 that drives the hydraulic actuators 2a to 6a is mounted. Although various functions for controlling the shovel 100 are mounted on the controller 16, descriptions of functions not directly related to the present invention are omitted.

  Specific calculation contents of each unit in the controller 16 of FIG. 3 will be described. The controller 16 includes an upper revolving body angle calculator C10, a relative angle calculator C11, a front attitude calculator C12, an operation determiner C20, a vehicle body attitude calculator C13, an operation instruction calculator C14, and a work support calculator. C15 is provided.

  The upper revolving unit angle calculation unit C10 calculates the turning center coordinates of the upper revolving unit 2 and the direction of the front device 1 according to the detection values of the position measuring device C01 and the inertial measuring device 12. Specifically, as shown in FIG. 4, the angle of a straight line passing through the positions of the two GNSS antennas 13 and 14 in plane coordinates is calculated from the coordinates of the main antenna 13 and the sub-antenna 14 calculated by the positioning terminal 15, Further, the angle θ of the front device 1 is calculated from the geometric relationship between the antennas 13 and 14 and the front work device 1.

When the excavator 100 is performing a turning operation, the angular velocity ω detected by the inertial measurement device 12 is integrated with the angle θ ₀ obtained from the positions of the GNSS antennas 13 and 14 as a starting point, whereby the front end is integrated. The angle θ may be calculated according to equation (3).

  The relative angle calculation unit C11 calculates a relative angle α formed between the upper revolving unit 2 and the lower traveling unit 3. For the calculation of the relative angle α, a detection value of the position measuring device C01 (the positions of the main antenna 13 and the sub-antenna 14 before and after the traveling operation by the lower traveling body 3) is used. The detection value of the inertial measurement device 12 and the output of the operation determination unit C20 can also be used. Since the calculation contents of the relative angle calculation unit C11 are the main features of the present embodiment, the details will be described later.

The front attitude calculation unit C12 calculates the attitude of the front device 1 based on the detection value of the attitude measurement device C02. The posture of the front device 1 includes not only the posture of each of the front members 4, 5, and 6 but also the claw tip position of the bucket 6, which is the tip of the front device 1. For example, as shown in FIG. 5, in a coordinate system (xb, yb, zb) whose origin is the boom foot pin which is the rotation center of the boom 4, the boom 4, the arm 5, and the bucket 6 (more precisely, the boom length L _Assuming that the angles (posture angles) of the _bm , the arm length L _am and the bucket length L _bk are θ _bm , θ _am and θ _bk , respectively, the claw tip position of the bucket 6 is expressed by the following equation (4). It can be obtained from equation (5).

Note that when a potentiometer is used as the posture measuring device C02, the posture angles θ _bm , θ _am , and θ _bk can be directly obtained. However, when an inertial measurement device or a cylinder stroke sensor is used, the detected value is used as the posture angle. Calculations for converting into θ _bm , θ _am , and θ _bk are also required.

  The body posture calculation unit C13 integrates information on the posture of the excavator 100 based on the calculation results of the upper revolving body angle calculation unit C10, the relative angle calculation unit C11, and the front posture calculation unit C12. More specifically, the coordinates of the boom foot pin in the world coordinate system can be calculated according to the turning center coordinates, the direction of the front device 1, and the dimensional information of the hydraulic shovel 100 calculated by the upper swing body angle calculating unit C10. Thereafter, when the coordinates of the boom foot pin are set as the origin and the bucket claw tip positions calculated by the front attitude calculator C12 are integrated, the bucket claw tip positions in the world coordinate system can be calculated. In addition, using the relative angle α between the upper revolving unit 2 and the lower traveling unit 3 computed by the relative angle computing unit C11 based on the turning center coordinates computed by the upper revolving unit angle computing unit C10, the lower traveling unit 3 (absolute angle) can be calculated.

  The operation support operation unit C14 performs an operation related to machine guidance to assist the operation of the operator based on the operation result of the vehicle body posture operation unit C13 and the operation content determined by the operation determination unit C20, and displays the instruction content on a display device. Output to C03. The contents of the support include displaying the positional relationship between a predetermined target plane and a bucket, and according to the coordinates of the bucket calculated by the vehicle body posture calculation unit C13 so that the tip of the bucket 6 does not go under the target plane. A display that prompts the user to operate the boom raising lever, a display that prompts the user to operate the traveling lever so that the orientation of the lower traveling body matches the work surface for the operation shown in FIG. 18, and the like can be given. The operation instruction calculation unit C14 may be provided with a guidance function for other operations, but the description is omitted because it has no direct relation to the present embodiment.

  The work support calculation unit C15 performs calculation related to machine control for automatically or semi-automatically controlling the operation of the excavator 100 based on the calculation result of the body posture calculation unit C13 and the operation content determined by the operation determination unit C20. Then, a command value for executing this operation is output to the hydraulic control device C04. The hydraulic control device C04 controls the operation of the excavator 100 including the front device 1 based on the input command value. As an example of semi-automatic control of the operation of the excavator 100, the front device 1 (more specifically, the claw tip of the bucket 6) is positioned on or above a target surface when operating the operation devices 9a and 9b. In some cases, the speed at which the vehicle 1 approaches the target surface is limited to a predetermined speed limit or lower.

  Next, the configuration of the relative angle calculation unit C11 will be described in detail with reference to the drawings.

<First embodiment>
FIG. 6 is an example of an embodiment of the relative angle calculation unit C11. In FIG. 6, a case is considered in which only the detection value of the position measurement device C01 is used as an input of the relative angle calculation unit C11. For convenience of explanation, the coordinates (position) of the main antenna 13 calculated by the position measurement device C01 at time t1 (first time) are coordinates 13a, the coordinates (position) of the sub-antenna 14 are coordinates 14a, and the time t2 ( The coordinates (position) of the main antenna 13 calculated by the position measuring device C01 at the second time) are called coordinates 13b, and the coordinates (position) of the sub-antenna 14 are called coordinates 14b.

  6 includes a first position information storage unit A01, a second position information storage unit A02, a first vehicle body angle calculation unit A03, a second vehicle body angle calculation unit A04, and a travel displacement angle calculation unit. A section A05, a deviation angle calculation section A06, a traveling displacement angle correction section A07, and a relative angle calculation section A08.

  The first position information storage unit A01 and the second position information storage unit A02 are configured in a storage area of a storage device in the controller 16.

  The first position information storage unit A01 stores the main antenna position 13a and the sub-antenna position 14a at time t1 (first time). The first position information storage unit A01 refers to information related to positioning accuracy, such as DOP (Dilution Of Precision) and position identification quality, output from the positioning terminal 15, and performs positioning with the accuracy required for subsequent calculations. The position information at the time is stored. For example, when the RTK is used, the location specifying quality is “RTK-FIX”, that is, the quality of “GGA” in the NMEA message, which is a standard format of GNSS, is 4. By confirming the above and storing the position information, the error of the positioning result can be reduced to about 2 cm. It is desirable that the shovel 100 is not operated from the time t1 onward until the above-mentioned position information is stored.

  The second position information storage unit A02 stores the main antenna position 13b and the sub-antenna position 14b at time t2 (second time). Like the first position information storage unit A01, the first position information storage unit A02 stores the position information when the desired positioning accuracy is guaranteed. Similarly, it is desirable not to operate the shovel 100 until the position information is stored.

  The relationship between time t1 and time t2 will be described with reference to the time chart of FIG.

  First, before the time t1, the operation of the shovel 100 is not restricted at all. At time t1, storage of the position information output from the position measuring device C01 is started, and the shovel 100 is stopped until time ta at which desired accuracy (for example, 2 cm of RTK-FIX) is guaranteed. Then, the storage of the position information ends at time ta.

  After the end of storing the position information at the time ta, the operation of the shovel 100 is permitted again. However, as described later, it is desirable that no operation other than traveling is performed from time ta to time t2.

  When the storage of the position information output from the position measurement device C01 is started again at the time t2, the operation of the shovel 100 is stopped until the time tb at which the position accuracy is guaranteed. Similarly, storage of the position information ends at time tb.

  By performing the above operation, it is possible to suppress the calculation error of the relative angle α between the lower traveling unit 3 and the upper revolving unit 2 due to the positioning error by the GNSS. In the following description, for simplicity, it is assumed that the accuracy of “RTK-FIX” is guaranteed even at times t1 and t2.

The first body angle calculation unit A03 is the direction (angle) of the upper revolving structure at time t1, based on the main antenna coordinates 13a and the sub-antenna coordinates 14a at time t1 stored in the first position information storage unit A01. It calculates the first vehicle body angle theta _1. Although the specific calculation is in accordance with FIG. 4, it is assumed here that the excavator 100 is arranged on a sufficiently smooth plane (no displacement in the height direction z) for the sake of simplicity. Assuming that the plane coordinates 13a of the main antenna 13 at time t1 are (x1, y1) and the plane coordinates 14a of the sub-antenna 14 are (x2, y2), a straight line passing through the antennas 13 and 14 at time t1 is a predetermined line. it can provide the angle theta ₁ which forms a reference line (in FIGS. 8 and 9 horizontal lines) by the following equation (6).

The second vehicle body angle calculation unit A04 is the direction (angle) of the upper revolving structure at time t2 based on the main antenna coordinates 13b and the sub-antenna coordinates 14b at time t2 stored in the second position information storage unit A02. calculating a second body angle theta _2. Assuming that the plane coordinates 13b of the main antenna 13 at time t2 are (x3, y3) and the plane coordinates 14b of the sub-antenna 14 are (x4, y4), a straight line passing through the antennas 13 and 14 at time t2 is a predetermined reference line. (See the horizontal lines in FIGS. 8 and 9) and the angle θ ₂ (see FIGS. 8 and 9) can be given by the following equation (7).

  The traveling displacement angle calculation unit A05 determines the position of one of the two antennas 13 and 14 at times t1 and t2 stored in the first position information storage unit A01 and the second position information storage unit A02 based on the position of one antenna. , And a traveling displacement angle ψ (φ), which is an angle formed by a straight line passing through the position of one of the antennas at time t1 and time t2 with a predetermined reference line. The traveling displacement angle ψ (φ) is the angle of the GNSS antenna generated by the traveling operation of the lower traveling unit 3 performed between time ta and time t2 after time t1.

  Here, the travel displacement angle ψ is calculated from the position of the main antenna 13 at times t1 and t2. Assuming that the operator has only operated the traveling lever between time ta and time t2 in FIG. 7, the angle ψ formed by a straight line passing through the main antenna coordinates 13a before traveling and the main antenna coordinates 13b after traveling is represented by the following equation. Calculate by equation (8).

  FIG. 8 shows an example of the above calculation. If the locus of the lower traveling body 3 is completely straight, the x coordinate of the main antenna coordinates 13a and 13b before and after traveling is the same, so that the traveling displacement angle ψ = 0 as shown in FIG. Also, θ1 = θ2 holds.

  FIG. 9 shows an example in which the relative angle α between the lower traveling structure 3 and the upper revolving structure 2 is different from that in FIG. As in FIG. 8, if the locus of the lower traveling body 3 is completely straight, θ1 = θ2 holds.

  8 and 9, the angle ９ calculated by the equation (8) is equal to the absolute angle of the lower traveling body 3. However, it should be noted that this is limited to the case where the locus of the lower traveling body 3 during the traveling operation is completely straight. That is, the locus of the lower traveling body 3 does not become a straight line because it normally meanders due to a slip or the like.

  The departure angle calculation unit A06 travels the undercarriage 3 based on the information stored in the first position information storage unit A01 and the second position information storage unit A02 and the calculation result of the first vehicle body angle calculation unit A03. A deviation angle δφ, which is an angle caused by meandering during operation, is calculated.

  Here, FIG. 10 shows an example of changes in the coordinates of the GNSS antenna when the deviation angle δφ occurs. For simplicity, consider a case where the coordinates 13a, 14a of the main antenna 13 and the sub-antenna 14 at the time t1 stored in the first position information storage unit A01 are on the X 'coordinate (two points 13a, 14a may be considered as taking the X 'axis). In FIG. 10 and thereafter, for simplicity of explanation, the travel displacement angle of the lower traveling body 3 will be described using φ with the X ′ axis set to 0 ° instead of ψ. Since 関係 and φ in FIG. 8.9 have the relationship “関係 + φ = 90 degrees”, they can be easily converted.

  First, assuming that the lower traveling body 3 can travel straight along the initial angle φ 'of the lower traveling body 3 (the angle of the lower traveling body 3 at t1), the coordinates of the antennas 13 and 14 at time t2 are as shown in FIG. 13c and 14c in FIG. Note that if the vehicle can travel straight, the vector connecting the main antenna coordinates 13c and the sub-antenna coordinates 14c is parallel to the X 'axis (the vector connecting the two coordinates 13a and 14a).

  However, in the actual traveling operation, the crawler-type lower traveling body 3 slips between the footwear and the ground and meanders. Therefore, each antenna 13 at time t2 stored in the second position information storage unit A02 is used. The coordinates of 14 are, for example, 13b and 14b. In such a case, the angle φ obtained by performing the calculation of Expression (8) using the coordinates of 13b and 14b becomes a value different from the initial angle of the lower traveling body 3 (φ ′ in FIG. 10). Would. The angle difference thus generated is referred to as a deviation angle δφ in the present application. As apparent from FIG. 10, the deviation angle δφ is the difference (δφ = φ′−φ) between the angle φ ′ formed by the lower traveling body 3 with the predetermined reference line (X ′ axis) and the traveling displacement angle φ at time t1. ).

(1) Approximation 1 of deviation angle δφ by angle θc
An example of a method of calculating the deviation angle δφ will be described with reference to FIGS. 11A and 11B. This example is accurate when the deviation angle δφ is sufficiently small.

  First, as shown in FIG. 11A, the moving distance of the main antenna 13 from time t1 to time t2 is 11, and the moving distance of the sub antenna 14 from time t1 to time t2 is 12, Assuming that the distance between the antennas 14 is H, the respective values can be calculated by the following equations (9), (10), and (11) using the coordinate values of the two antennas 13 and 14 at times t1 and t2.

  Note that, in the expression (11), the main antenna coordinates 13a and the sub-antenna coordinates 14a at the time t1 stored in the first position information storage unit A01 are used, but the time t2 stored in the second position information storage unit A02 is used. May be used as the coordinates 13b and 14b.

  Here, it is noted that the orbital change due to slippage between the footwear and the ground can be approximated as a rotational movement about the far point CO. When the movement distance l1 of the main antenna 13 is a part of the outer circumference of the circle of radius (H + R), The moving distance 12 of the antenna 14 can be regarded as a part of the outer circumference of the circle having the radius R. At this time, the respective moving distances l1 and l2 can be approximated by the following equations.

  In (12) and (13), since the unknown variables are two variables of R and θc, R and θc can be calculated numerically by simultaneously setting (12) and (13). That is, in this example, it is assumed that the moving distances l1 and l2 of the two antennas 13 and 14 are fan-shaped arcs (the radii are R + H and R) having the same center and a deviation angle δφ as the central angle θc. Then, the deviation angle δφ is calculated.

  Considering a triangle having the sub-antenna coordinates 14a and 14b and the far point CO as vertices at times t1 and t2 stored in the first position information storage unit A01 and the second position information storage unit A02, 14) Equation may be added.

  However, although equation (14) is an equation using the sub-antenna coordinates, the main antenna coordinates 13a and 13b may be used instead.

(2) Approximation 2 of deviation angle δφ by angle θc
Further, let us consider a case where an X′-Y ′ coordinate system is used to connect the coordinates 13a and 14a of the main antenna 13 and the sub-antenna 14 at the time t1 stored in the first position information storage unit A01 (FIG. 10). 11b, the angle formed by the straight line passing through the coordinates 13b and 14b of the main antenna 13 and the sub-antenna 14 at the time t2 with the X axis is θc, so that the arctangent defined by the following equation (15) is obtained. Θc can also be obtained by a function.

  (X3 ′, y3 ′) and (x4 ′, y4 ′) in the above equation (15) are the main antenna coordinates at time t2 stored in the second position information storage unit A02 in the X′-Y ′ coordinate system. 13b and sub-antenna coordinates 14b.

(3) Approximation of Deviation Angle δφ by Angle θd When the deviation angle δφ is sufficiently small, it can be considered that δφ = θc, but otherwise, the approximation accuracy may not be high. Next, an example of a method of increasing the approximation accuracy as compared with the case of approximation by θc will be described with reference to FIG.

  First, as shown in FIG. 12A, the coordinates 14d of the virtual sub-antenna at the second time t2 are calculated using the angle φ before and after the movement of the main antenna 13 calculated by Expression (8). The coordinates 14d indicate the position of the sub-antenna 14 at time t2 assuming that the lower traveling body 3 can travel straight along the travel displacement angle φ by the traveling operation performed between time ta and time t2 after time t1. Indicates a virtual position. Assuming that the coordinates 14d of the virtual sub-antenna 14 are (xp, yp), it can be specifically given by the following equations (16) and (17).

  That is, xp and yp can be defined based on the moving distance l1 of the main antenna 13 from time t1 to time t2, the coordinates 14a (x2, y2) of the sub-antenna 14 at time t1, and the traveling displacement angle φ.

  Since the distance between the main antenna 13 and the sub-antenna 14 at the same time is constant (the distance is given by H in Expression (11)), the sub-antenna coordinates at time t2 stored in the second position information storage unit A02 are stored. 14b and the virtual sub-antenna coordinates 14d at time t2 are arranged on the circumference of the radius H centered on the main antenna coordinates 13b at time t2 stored in the second position information storage unit A02. This is shown in FIG. 12b.

  In this example, a straight line passing through the sub-antenna coordinates 14a at time t1 and the virtual sub-antenna coordinates 14d at time t2, and a straight line passing through the sub-antenna coordinates 14b at time t2 and the virtual sub-antenna coordinates 14d at time t2. The deviation angle δφ is approximated by the formed angle θd. θd can be calculated by using the cosine theorem for a triangle having three coordinates 14a, 14b, and 14d at the vertices and having three sides a, b, and c shown in FIG. 12B. Side a is a side connecting two vertices 14a and 14b, side b is a side connecting two vertices 14a and 14d, and side c is a side connecting two vertices 14d and 14b.

  When the deviation angle δφ is small, in FIG. 12B, the sub-antenna coordinates 14b approach the virtual sub-antenna coordinates 14d along the circumference, so that θd gradually approaches 0. Similarly, when the sub-antenna coordinates 14b approach the virtual sub-antenna coordinates 14d along the circumference, it can be confirmed that the above-described θc also approaches 0. This is the reason that "if the deviation angle is sufficiently small, it can be considered that δφ = θc".

FIG. 21 shows the relationship between the deviation angle δφ and the approximate calculated values θc and θd.
First, as shown in Expression (15), θc is calculated as the rotation angle around the X ′ axis using the coordinate values of the two points 13b and 14b at the time t2 at which measurement is actually possible.

  On the other hand, as shown in equations (18) to (21), θd is the coordinate value of the two points 14a and 14b at times t1 and t2 at which measurement is actually possible, and the coordinate value of the virtual positioning point 14d obtained by calculation. That is, using the coordinate values of the three points, the angle is calculated as an angle formed by two straight lines 14a-14d and 14b-14d.

  Here, the straight line 14d-14b is extended, and the coordinates of the intersection with the X 'axis are defined as 14e. If the traveling distance by the lower traveling unit 3 is sufficiently long, the straight lines 14a to 14c and the straight lines 14d to 14e have an approximately parallel relationship. Using this parallel relationship, it can be confirmed that θd and δφ match. This is the reason why δφ can be accurately approximated by θd.

  When attention is paid to the geometric relationship between the points in FIG. 21, it seems that there is no clear relationship between the deviation angles δφ and θc. However, as shown in FIG. 12B, the values of θc and θd gradually approach as the deviation (deviation angle δφ) of the undercarriage 3 decreases (ie, when 14b and 14d are closer). This relationship between θc and θd is the reason that there is considerable validity in using θc for calculating the deviation angle δφ. However, it should be noted that θc is merely an approximate value of “θd, which is an approximate value of δφ”, and is often inferior to θd in terms of accuracy.

  The traveling displacement angle correction unit A07 corrects the traveling displacement angle φ by taking into account the deviation angle generated during traveling based on the calculation results of the traveling displacement angle calculation unit A05 and the deviation angle calculation unit A06. The traveling displacement angle φ 'is calculated.

  More specifically, the correction is performed by the following equation. That is, a value obtained by adding the deviation angle δφ to the traveling displacement angle φ is set as the corrected traveling displacement angle φ ′. The travel displacement angle φ 'after the correction is the angle (direction) of the lower traveling body 3 before the traveling operation (for example, at time t1).

  Note that, as shown in FIGS. 8 and 9, when the movement of the undercarriage is completely straight, the deviation angle δφ = 0 is established, so that φ ′ = φ.

The relative angle calculation unit A08 calculates a relative angle α formed by the upper revolving unit 2 and the lower traveling unit 3 based on the calculation results of the first vehicle body angle calculation unit A03 and the traveling displacement angle correction unit A07. Specifically, the calculation may be performed according to “α = θ ₁ −φ ′”. That is, the value obtained by subtracting the travel displacement angle phi 'after correction is the relative angle α of the upper frame 2 and the lower traveling body 3 at time t1 from the first body angle theta _1.

  As described above, in the working machine provided with the crawler type lower traveling body 3, the angle of the lower traveling body 3 is φ ′ (FIG. 10) at time t1 before traveling, for example, and the lower traveling body 3 is kept in that state. Even if an operation of moving straight ahead is input, the lower traveling body 3 meanders due to slippage during traveling or the like, and the angle of the lower traveling body 3 at time t2 after traveling is different from the angle before traveling (see FIG. 10). ). Therefore, even if the moving direction φ is calculated from a change in the position of one of the two GNSS antennas 13 and 14 installed on the upper revolving unit 2 before and after traveling, the angle φ ′ of the lower traveling unit 3 before traveling is accurately calculated. Was difficult to calculate.

  However, since the work machine of the present embodiment includes the controller 16 having the relative angle calculation unit C11 for executing the above calculation, the deviation angle δφ (δφ) generated as a result of the lower traveling body 3 meandering during the traveling operation. = Φ′−φ) with the other angles θc and θd with high accuracy, the angle φ ′ of the lower traveling unit 3 at the time t1 can be calculated. Thereby, the relative angle α between the upper revolving unit 2 and the lower traveling unit 3 at the time t1 can be calculated. Thereafter, if the revolving angles of the upper revolving unit 2 are integrated, the upper revolving unit 2 and the lower traveling unit at a desired time can be calculated. The relative angle α of the body 3 can be calculated. Particularly, the present embodiment has an advantage in that a series of angles θc, θd, and α can be calculated from only the positioning results of the two GNSS antennas 13 and 14. The method of using the positioning result of GNSS is different from the configuration in which the rotation axis is provided with the rotation angle sensor shown in Patent Document 2, and even if a failure occurs in the GNSS (position measurement device C01), replacement and repair are very easy. It is. In recent years, hydraulic excavators equipped with two GNSS antennas have been increasing due to the progress of computerized construction, and application to such excavators is superior in terms of initial cost compared to a configuration equipped with a dedicated rotation angle sensor. There is.

  Further, if the relative angle α calculated as described above is displayed on the display device C03 in the cab 9, for example, the display device will be displayed even if the operator forgets the direction of the lower traveling body 3 during the work by the front device 1. Since the relative angle between the upper revolving unit 2 and the lower traveling unit 3 can be ascertained at any time by referring to C03, it is possible to prevent the vehicle from moving forward in the wrong direction when starting the traveling operation after the work by the front device 1 is completed. The application of the relative angle α is not limited to this, and various forms can be used in the machine guidance function and the machine control function.

<Second embodiment>
FIG. 13 is a functional block diagram of a relative angle calculation unit C11 according to the second embodiment. The relative angle calculation unit C11 of the present embodiment is characterized in that the output of the inertial measurement unit (IMU) 12 is input to the deviation angle calculation unit D06 and is used for the calculation contents in the deviation angle calculation unit D06. There is. Except for the contents described below, other parts having the same names as those of the first embodiment are assumed to execute the same processes as those of the first embodiment, and description thereof will be omitted.

  The inertial measurement device 12 can detect the sum (ω = ωu + ωb) of the angular velocity ωu of the upper swing body 2 and the angular velocity ωb of the lower traveling body 3. Here, if the condition that the upper revolving superstructure 2 is not rotated (ωu = 0) is imposed between the time t1 and the time t2, the detection value of the inertial measuring device 12 becomes the angular velocity ω = ωb of the lower traveling vehicle. Therefore, if this angular velocity is used, the above-described angle θc can be calculated by the following equation (23). The integration interval in equation (23) can be set, for example, from time t1 to time t2.

  That is, the deviation angle calculation unit D06 of the present embodiment calculates the integral value of the angular velocity detected by the inertial measurement device 12 from time t1 to time t2 as the deviation angle δφ. As described above, even when the deviation angle δφ is calculated, the relative angle α between the upper revolving unit 2 and the lower traveling unit 3 can be calculated. However, when a high-precision inertial measurement device (IMU) 12 is used to detect the angular velocity ωb of the undercarriage 3 as in the present embodiment, θc is calculated based on the GNSS positioning result and the equations (14) and (15). Can be obtained more accurately than the method of the first embodiment for calculating In recent years, with the progress of computerized construction, hydraulic shovels equipped with an inertial measurement unit (IMU) 12 for detecting the inclination angle of the upper-part turning body 2 have increased, and the present embodiment is applied to such a hydraulic shovel. In this case, there is an advantage in terms of initial cost as compared with a configuration including a dedicated rotation angle sensor.

  In the present embodiment, the angular velocity ωb of the lower traveling body is acquired by the inertial measurement device 12 attached to the upper revolving superstructure 2, but any other angular velocity detection sensor that can acquire the angular velocity ωb of the lower traveling body 3 is used. It does not matter. Alternatively, the inertial measurement device 12 may be attached to the lower traveling body 3 to detect the angular velocity ωb.

<Third embodiment>
FIG. 14 is a functional block diagram of a relative angle calculation unit C11 according to the third embodiment. In the present embodiment, in addition to the configuration of the second embodiment, the output of the operation determination unit C20 is input to the relative angle calculation unit C11, and is used for calculation in the departure angle calculation unit E06 and the travel displacement angle calculation unit E05. . Except for the contents described below, the other parts having the same names as those of the second embodiment execute the same processes as those of the second embodiment, and descriptions thereof will be omitted.

  The operation determination unit C20 receives a signal output from the operation detection device C05 and monitors, for example, the operation direction and operation amount of the operation levers 9a, 9b, 9c, and 9d. Determine whether you have entered an operation. The operation determination unit C20 also receives not only the operation levers 9a, 9b, 9c, and 9d but also signals output from input devices including a console panel in the cab 9, and inputs the operation contents ( (Input contents).

  The deviation angle calculation unit E06 performs a calculation using the output of the operation determination unit C20 in addition to the calculation performed by the deviation angle calculation unit D06 of the second embodiment. For example, if the turning operation is performed during the traveling operation of the lower traveling body 3, the upper revolving body 2 rotates (ωu ≠ 0), so that θc cannot be calculated by the equation (19). For this reason, when the operation determining unit C20 determines that the turning operation is being performed, the departure angle calculating unit E06 stops calculating θc by the equation (19).

  The travel displacement angle calculation unit E05 performs not only the calculation described above, but also a calculation using the output of the operation determination unit C20. Assuming that the deviation angle δφ is sufficiently small, the integral value of the angular velocity detected by the inertial measurement device (angular velocity detection sensor) 12 coincides with the angle change Δθ of the upper swing body 2 as shown in the following equation (24). .

By using Δθ in equation (24), it is possible to calculate the travel displacement angle φ even when the turning operation is performed during the travel operation between time t1 (first time) and time t2 (second time). Can be done. Specifically, than the angle theta ₁ which the angle theta ₂ which the right turning operation as shown in FIG. 15 is calculated by the performed second body angle calculating unit A04 is calculated by the first vehicle body angle calculating unit A03 Also causes a change in Δθ. Therefore, the main antenna coordinates and the sub-antenna coordinates at time t2 are respectively rotated by Δθ with respect to the turning center in the direction opposite to the turning operation (ie, the left turning direction) (coordinate conversion). The main antenna coordinates and the sub-antenna coordinates at time t2 obtained after the rotation operation are set as (x3c, y3c) and (x4c, y4c), respectively, and these coordinates are regarded as the coordinates 13b and 14b of the first embodiment, and the first By performing the same calculation as in the embodiment, the relative angle α can be calculated.

  Note that the above calculation is based on the premise that "the deviation angle δφ is sufficiently small". Therefore, when the turning operation is performed, the calculation accuracy of the relative angle α is likely to decrease. For this reason, during the calculation of the relative angle α (during the traveling operation by the lower traveling unit 3), a display for notifying the operator that the turning operation is not performed is output to the display device C03 so that the operator does not perform the turning operation. It is desirable.

  An example of a calculation flow of the controller 16 of the present embodiment including the relative angle calculation unit C11 configured as described above will be described with reference to FIG. In the calculation flow of the controller 16 of the first and second embodiments, the processes (S01, S02, S07, S08a, S08b) related to the operation determination unit C20 and the inertial measurement device 12 may be omitted.

  When the power is set from the OFF state to the ON state, the controller 16 starts the processing in FIG. First, in S1, the operation determination unit C20 determines whether the operator intends to calibrate the relative angle between the upper revolving unit 2 and the lower traveling unit 3 based on the operation content of the console in the cab 9. . On the console, a calibration start button (input device) for outputting a calibration instruction for instructing the controller 16 to calibrate the relative angle between the upper revolving unit 2 and the lower traveling unit 3 based on an input from an operator is provided. When the operator presses the calibration start button, a calibration instruction is output to the controller 16 (operation determining unit C20). When this calibration instruction is input, the operation determining unit C20 determines that the operator has an intention to calibrate the relative angle.

  If the calibration start button is not pressed and the operation determination unit C20 determines that calibration of the relative angle is not required in S01, the process shifts to S02 to perform a normal operation. The normal operation means, for example, performing guidance and control (machine control) calculations necessary for performing an excavation operation.

  If the calibration start button is pressed and the operation determination unit C20 determines that calibration of the relative angle is required in S01, the process proceeds to S03. In S03, the operation instruction calculation unit C14 displays on the display device C03 that the "calibration mode" is currently selected. Note that, when the calibration mode is selected, the operator is prompted not to perform the turning operation by continuously displaying, for example, a message “Do not perform the turning operation” on the display device C03 by the operation instruction calculating unit C14. It is desirable to ensure calibration accuracy.

  Next, in S04, the relative angle calculation unit C11 determines whether or not the positioning results of the main antenna 13 and the sub-antenna 14 by the positioning terminal 15 have been performed with sufficient accuracy, and the position identification quality becomes “RTK-FIX”. It is determined by whether or not. This determination may be made based on the value of DOP as described above. If the accuracy is insufficient, the operation instruction calculation unit C14 displays on the display device C03 that the operation is in standby without operation until accurate positioning is performed. Note that if positioning cannot be performed with desired accuracy even after a predetermined period of time due to the poor reception environment of the GNSS, a message or figure urging the user to change the calibration location (move to another location in the running operation) is displayed. The information may be displayed on the display device C03. S04 can be omitted.

  If it is confirmed in S04 that high-accuracy positioning has been performed, the process proceeds to S05. In S05, the relative angle calculation unit C11 stores the positioning result in the first position information storage unit A01 as the position information of the two antennas 13 and 14 at time t1 (first time) (first position storage processing). . After the positional information of the two antennas 13 and 14 is stored at time t1, the process proceeds to S06.

  In S06, the operation instruction calculation unit C14 displays, for example, a message “Please input a straight-ahead operation” on the display device C03, and prompts the operator to perform a straight-ahead operation on the lower traveling unit 3 via the operation levers 9c and 9d (specifically, Specifically, the two operation levers 9c and 9d are tilted in the same direction by the same amount). At this time, in order to improve the approximation accuracy of the aforementioned θc and θd to improve the accuracy of the relative angle calculation, the minimum mileage suitable for calibration or the mileage after the straight-ahead operation input is displayed. Is also good. The travel distance of the undercarriage 3 can be calculated, for example, from a change in the positioning result of GNSS. Alternatively, the calculation may be performed by detecting the number of revolutions of the traveling hydraulic motor 3a or the drive wheels of the crawler belt with a sensor.

  Next, in S07, the operation determining unit C20 determines whether or not the turning operation has been performed by the operator during the straight-ahead operation. If it is determined that the turning operation has not been performed, the process proceeds to S09. If it is determined that the turning operation has been performed, the processing of S08a and S08b is executed.

  In S08a, the traveling displacement angle calculation unit E05 integrates the angular velocity ω detected by the inertial measurement device 12 during the turning operation with time in order to calculate the angle change Δθ during the turning operation. The calculated Δθ is used in S12 to be described later to perform a rotation operation (coordinate conversion) in the opposite direction to the turning operation by turning the main antenna coordinates and the sub-antenna coordinates at time t2 by Δθ with respect to the turning center, respectively. You. As described with reference to FIG. 15, the main antenna coordinates and the sub-antenna coordinates at time t2 obtained after the rotation operation are set to (x3c, y3c) and (x4c, y4c), respectively, and these coordinates are set in the first embodiment. The relative angle α can be calculated by performing the same calculation as in the first embodiment by regarding the coordinates 13b and 14b as.

  In S08b, the operation instruction calculation unit C14 displays, for example, a message on the display device C03 that "the relative angle may have low accuracy because the turning operation was performed during traveling". As a result, the operator is informed that the calculation result of the relative angle may have low accuracy due to the turning operation being performed during the traveling operation of the lower traveling body 3. Instead of such a message, a message urging the operator to press the calibration start button again to perform the calibration operation again may be displayed on the display device C03.

  Next, in S09, the operation instruction calculation unit C14 hides the straight traveling instruction displayed on the display device C03 from S06, and urges the operator to stop the traveling operation by the operation levers 9a and 9b. Instead, a display instructing to stop the straight-ahead operation may be displayed on the display device C03. For the purpose of improving the approximation accuracy of θc and θd, a condition that a predetermined time has elapsed since the start of the input of the driving operation may be set as a condition for executing S09 after S06, or the positioning result of the GNSS may be set to a predetermined value. The fact that the distance has changed by more than the distance may be set. As a result, a sufficient traveling distance can be secured, so that the approximation accuracy of θc and θd is improved, and as a result, the accuracy of the relative angle α is also improved.

  When the traveling operation is stopped, the positioning accuracy of the GNSS is determined in S10 as in S04. After confirming that the positioning with sufficient accuracy has been performed, the process proceeds to S11.

  In S11, the relative angle calculation unit C11 stores the positioning result in the second position information storage unit A02 as the position information of the two antennas 13 and 14 at time t2 (second time) (second position storage processing). . When the positional information of the two antennas 13 and 14 is stored at time t2, the process proceeds to S12. When the process reaches S11, all the inputs of the relative angle calculation unit C11 in FIG. 14 are completed, so the process transits to the process of “relative angle calculation” in S12, and calculates the relative angle α. Since the calculation of the relative angle α is as described above, the description is omitted.

  As described above, in the present embodiment, the calibration mode is triggered by the depression of the calibration start button provided in the operator's cab 9, and the processing sequentially performed by the relative angle calculation unit C11 for calculating the relative angle α is performed. Among them, a display for instructing the start of the traveling operation at a timing at which the traveling operation is required (S06) and a display for instructing the end of the traveling operation at a timing when the traveling operation is no longer necessary (S09) are made. . This facilitates the start and end of the traveling operation at an appropriate timing by the operator who sees these displays, so that smooth calibration can be performed and improvement in calibration accuracy can be expected.

  Further, in the controller 16 of the present embodiment, the position of the main antenna 13 and the position of the sub-antenna 14 calculated by the positioning terminal 15 when the calibration instruction is input via the calibration start button on the console in the cab 9 is calculated at the time t1. Is stored in the first position information storage unit A01 as the positions 13a and 14a of the main antenna 13 and the sub-antenna 14 in (S01), and after the calibration instruction is input, the driving operation is input via the operating devices 9c and 9d, and thereafter the driving is performed. The positions of the main antenna 13 and the sub-antenna 14 calculated by the positioning terminal 15 when the operation input is stopped are stored in the second position information storage unit A02 as the positions 13b and 14b of the main antenna 13 and the sub-antenna 14 at time t2. (S11). This makes it possible to automatically acquire the position information of the main antenna 13 and the sub-antenna 14 required for calculating the relative angle at appropriate timing before and after the start of the running operation by the lower running body 3.

  The timing at which the positions of the two antennas 13 and 14 are stored in the controller 16 is determined when the location specifying quality is “RTK-FIX” as determined in S04 and S10 of the flow in FIG. It is preferable to set the time when the variation in the positioning result due to the error becomes equal to or less than a predetermined value. By configuring the controller 16 in this manner, the accuracy of the relative angle α can be improved.

  Further, in the controller 16 of the present embodiment, the operation levers 9a, 9b, 9c, 9c, 9c, 9c, 9c, 9c, 9c, 9c, 9d, 9c, 9d are stopped after the input of the calibration instruction by the calibration start button (S03) until the input of the traveling operation by the operation levers 9c, 9d is stopped (S09). As the display of the operation instruction using 9d, only the traveling operation instruction via the traveling operation levers 9c and 9d is displayed (S06). That is, the operation permission by the display is limited to only the traveling operation. Thus, it is possible to prevent a decrease in the approximation accuracy of the relative angle α due to the input of a turning operation, which is another operation during the traveling operation. If a message prompting the user not to input the turning operation during the same period (S03-S09) is displayed on the display device C03, it is possible to suppress the turning operation during the calibration operation (including during the traveling operation), and to perform the relative operation. Ensuring the accuracy of corner calibration is promoted. However, this display may be limited to the period from S06 to S09 during which the traveling operation is required.

<Others>
Note that, in FIG. 10 described above, the case where the posture of the shovel (upper revolving superstructure 2) at time t2 is rotating clockwise compared to the posture at time t1 (that is, the case where the shovel meanders rightward during traveling). As an example, it is needless to say that there is a case where the vehicle is rotating left (that is, a case where the vehicle is meandering leftward). In this case, the relative angle φ can be calculated in the same manner as described above.

  The present invention is not limited to the above embodiment, and includes various modifications without departing from the gist of the invention. For example, the present invention is not limited to one having all the configurations described in the above embodiments, but also includes one in which some of the configurations are deleted. Further, a part of the configuration according to one embodiment can be added to or replaced by the configuration according to another embodiment.

  Even if some or all of the components related to the controller 16 and the functions and execution processes of the components are realized by hardware (for example, a logic that executes each function is designed by an integrated circuit). good. Further, the configuration of the controller 16 may be a program (software) that realizes each function of the configuration of the controller 16 by being read and executed by an arithmetic processing unit (for example, a CPU). Information related to the program can be stored in, for example, a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), a recording medium (magnetic disk, optical disk, etc.), and the like.

DESCRIPTION OF SYMBOLS 1 ... Front work apparatus (front apparatus), 2 ... upper revolving superstructure, 3 ... lower traveling body, 9c ... traveling operation lever (operating device), 12 ... inertia measuring device (angular velocity detection sensor), 13 ... main antenna (1st) Antenna), 14 sub-antenna (second antenna), 15 positioning terminal, 16 controller, A01 first position information storage unit (storage device), A02 second position information storage unit (storage device), A03 A first vehicle body angle calculator, A04: second body angle calculator, A05: travel displacement angle calculator, A06: departure angle calculator, A07: travel displacement angle corrector, A08: relative angle calculator, C03: display device , C20: operation determination unit, θ ₁ : first vehicle body angle (vehicle angle), ψ, φ: travel displacement angle, δφ: deviation angle, φ ': corrected travel displacement angle, θc: approximate angle of deviation angle, θd: approximate angle of deviation angle Every time

Claims (7)

A lower traveling body of a crawler type; an upper revolving body pivotally mounted on the upper part of the lower traveling body; a first antenna and a second antenna mounted on the upper revolving body; In a working machine comprising: a positioning terminal that calculates the position of each of two antennas; and a controller that calculates a relative angle between the upper revolving unit and the lower traveling unit.
The controller is
The position of the first antenna and the second antenna calculated by the positioning terminal at a first time and the positioning terminal at a second time after the lower traveling body performs a running operation after the first time. A storage device for storing the calculated positions of the first antenna and the second antenna;
A vehicle body angle calculation unit configured to calculate a first vehicle body angle that is an angle of the upper revolving unit at the first time from the positions of the first antenna and the second antenna at the first time;
A travel in which a straight line passing through the position of the first antenna at the first time and the second time is an angle formed with a predetermined reference line based on the position of the first antenna at the first time and the second time. A travel displacement angle calculation unit for calculating a displacement angle,
Based on the positions of the first antenna and the second antenna at the first time and the second time, the difference between the angle formed by the lower traveling body with the reference line and the travel displacement angle at the first time is determined. A deviation angle calculator for calculating a certain deviation angle;
A travel displacement angle correction unit that corrects the travel displacement angle using the deviation angle;
A relative angle calculation unit configured to calculate a relative angle between the upper revolving unit and the lower traveling unit at the first time based on the traveling displacement angle corrected by the traveling displacement angle correction unit and the first vehicle body angle. A working machine characterized by that: The work machine according to claim 1,
The departure angle calculation unit includes:
Based on the positions of the first antenna and the second antenna at the first time and the second time, the moving distances of the first antenna and the second antenna between the first time and the second time are determined. , Calculating the distance between the first antenna and the second antenna,
A work machine for calculating the departure angle, assuming that the moving distances of the first antenna and the second antenna are each a sectoral arc having the same center and the departure angle as a central angle. The work machine according to claim 1,
The departure angle calculation unit includes:
Calculating a movement distance of the first antenna from the first time to the second time based on the position of the first antenna at the first time and the second time;
Based on the travel distance of the first antenna, the position of the second antenna at the first time, and the travel displacement angle, it is assumed that the traveling operation has allowed the lower traveling body to travel straight along the travel displacement angle. Calculating the virtual position of the second antenna at the second time in the case where
A straight line passing through the position of the second antenna at the first time and the virtual position of the second antenna at the second time, the position of the second antenna at the second time, and the position of the second antenna at the second time. The angle formed by a straight line passing through the virtual position of the two antennas is defined as the deviation angle, and the deviation angle is defined as the position of the second antenna at the first time and the second time and the second antenna at the second time. A work machine that calculates based on the virtual position of the work machine. The work machine according to claim 1,
The position of the first antenna and the position of the second antenna at the first time and the second time stored in the storage device are the position of the first antenna and the position of the second antenna by the positioning terminal. A work machine characterized in that the data is data when a variation in a calculation result becomes equal to or less than a predetermined value. The work machine according to claim 1,
An input device for outputting a calibration instruction for instructing the controller to calibrate a relative angle between the upper revolving unit and the lower traveling unit based on an input from an operator;
An operating device for inputting a traveling operation for the lower traveling body,
The controller is
The positions of the first antenna and the second antenna calculated by the positioning terminal when the calibration instruction is input via the input device are defined as the positions of the first antenna and the second antenna at the first time. Stored in the storage device,
The driving operation is input via the operating device after the input of the calibration instruction, and the position of the first antenna and the second antenna calculated by the positioning terminal when the input of the driving operation is stopped thereafter is calculated by the control unit. A work machine storing the positions of the first antenna and the second antenna at a second time in the storage device. The work machine according to claim 5,
A display device for instructing an operator to perform an operation via the operation device;
The display device performs a display for instructing an operator to input only the traveling operation via the operation device from after the input of the calibration instruction until the input of the traveling operation is stopped. Working machine. The work machine according to claim 1,
An angular velocity detection sensor attached to the upper rotating body;
The work machine according to claim 1, wherein the deviation angle calculation unit calculates, as the deviation angle, an integral value of the angular velocity detected by the angular velocity detection sensor from the first time to the second time.

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