JP2022029755A - Control device of article movement mechanism - Google Patents

Abstract

To provide a control device that can appropriately change an operation mode of an article movement mechanism in response to occurrence of an event, without stopping the article movement mechanism such as a cargo handling robot and an AGV.SOLUTION: A control device comprises operation plan revising means and control means. The operation plan revising means revises a formulated operation plan in which a plurality of passing-points including a starting point and an ending point of a moving line of an article movement mechanism which is moving an article and pieces of passing time at which the article movement mechanism passes through the respective passing-points are set, without changing the passing-points, of set values in the operation plan, to formulate a revised operation plan in which pieces of the passing time are delayed or put ahead. The control means operates the article movement mechanism on the basis of whether there is a factor inhibiting operation of the mechanism on the moving line. During the operation, the control means controls the operation of the article movement mechanism in accordance with the operation plan when there is no factor; and makes the operation plan revising means formulate a revised operation plan when there is the factor and controls the operation of the article movement mechanism in accordance with the revised operation plan.SELECTED DRAWING: Figure 1

Description

An embodiment of the present invention relates to various mechanisms for moving an article (article moving mechanism), for example, a device for controlling the operation of a robot for handling an article or an automatic guided vehicle for transporting an article (control device).

Various goods such as unloaded luggage, parts, and products are handled at goods distribution centers and the like. For example, the articles accumulated in the accumulation area are picked by a cargo handling robot and moved by a transport device or the like. The cargo handling robot is, for example, a manipulator (robot arm) provided with a tool (also called an end effector) for handling an article at the tip of the arm. The tool has a gripping mechanism (article gripping mechanism) for gripping and picking an article from the accumulation area. As the article gripping mechanism, a suction mechanism for adsorbing an article with air is widely used. The transport device transports the article to the next process such as sorting and assembling. As the transport device, for example, in addition to a belt conveyor and a roller conveyor, an automatic guided vehicle (hereinafter referred to as AGV (Automatic Guided Vehicle)) or the like is used.

Each of the cargo handling robot and the AGV is an example of an article moving mechanism, and is a movable body whose operation plan is formulated in advance in consideration of work efficiency and safety and operates according to the formulated motion plan. However, if an unexpected (unexpected) change occurs in the operating environment of these movable bodies, it may cause inconvenience if the operation is continued according to the established motion plan. Hereinafter, such an unexpected change in the operating environment of a movable body is referred to as an event. In other words, the event is a trigger factor for changing the movement mode of the movable body. As such an event, for example, a case where a worker or a dolly enters the movable range of a cargo handling robot, a case where an article is not properly gripped by an article gripping mechanism, and the like are assumed. Further, for example, when a worker or the like enters the running path of an AGV, there is a possibility that traffic congestion or entry of another AGV into the running path may occur due to an operation delay of the AGV or the like, which is also assumed as an event.

When these events occur, for example, it is possible to temporarily stop the cargo handling robot or AGV, re-formulate the operation plan, and then restart the operation of the cargo handling robot or AGV according to the re-formulated operation plan. As a result, it is possible to avoid a collision between the cargo handling robot or AGV and an obstacle, and to prevent damage due to dropping of an article, but the work efficiency of cargo handling is lowered by the amount of temporarily stopping the cargo handling robot or the like. In the case of swiftly loading and unloading a wide variety of large quantities of articles, it is required to improve work efficiency without stopping movable objects such as cargo handling robots and AGVs even when an event occurs.

Japanese Patent No. 6123307 Japanese Patent No. 5904445

Therefore, we provide a control device that appropriately changes the operation mode of the article moving mechanism in response to the occurrence of an event without stopping the article moving mechanism such as a cargo handling robot or AGV.

The control device of the embodiment is a device for controlling the operation of the article moving mechanism for moving the article, and includes an operation plan correction means and a control means. The motion plan correction means was formulated by setting a plurality of waypoints including the start point and the end point of the flow line of the article movement mechanism at the time of moving the article and the passing time when the article movement mechanism passes through each waypoint. Of the set values of the motion plan, formulate a modified motion plan in which the motion plan is modified by delaying or advancing the passing time without changing the waypoint. The control means operates the article moving mechanism from the start point to the end point based on the presence or absence of a factor that hinders the operation of the article moving mechanism in the flow line. At that time, the control means controls the operation of the article movement mechanism according to the motion plan when there is no factor that hinders the operation of the article movement mechanism in the flow line, and when the factor exists, the control means becomes the motion plan correction means. A modified motion plan is formulated, and the operation of the article moving mechanism is controlled according to the modified motion plan.

The block diagram of the cargo handling apparatus provided with the control apparatus of 1st Embodiment. As an example of the waypoint data in the first embodiment, the figure which shows the time variation of the operation angle in a predetermined joint part of an arm part. The figure which shows an example of the waypoint data table (the waypoint data table) in 1st Embodiment. As one aspect before the correction of the waypoint data in the first embodiment (an example of the waypoint data set in the motion plan), the figure which shows the time variation before the correction of the motion angle in a predetermined joint part of an arm part. As one aspect before the correction of the waypoint data in the first embodiment (an example of the waypoint data set in the motion plan), the figure which shows the time variation after the correction of the motion angle in a predetermined joint part of an arm part. The figure which shows the control flow of the article movement processing in the control apparatus of the cargo handling apparatus of embodiment. The figure which shows the control flow of the event processing in the control apparatus of the cargo handling apparatus of embodiment. The block diagram of the automatic driving system including the control device of 2nd Embodiment. The figure which shows an example of the waypoint data table (the waypoint data table) in the 2nd Embodiment. The figure which shows the control flow of the driving process in the control device and the management device of the automatic driving system of 2nd Embodiment.

Hereinafter, the control device of the article moving mechanism according to the embodiment will be described with reference to FIGS. 1 to 10. The control device controls the operation of the article moving mechanism. The article moving mechanism is various mechanisms for moving the article, and corresponds to, for example, a robot that handles the article and an automatic guided vehicle (AGV) that conveys the article. Goods are tangible items that can be handled, such as parcels, parcels, packages including mail, various parts and products. The article includes not only the article itself, but also a tangible object in which the article is packed or packaged. It is assumed that the mode (shape, size, weight, material, etc.) of the article is not uniform but various, but it may be uniform. As the material (including the packing state and the packaging state) of the article, both an article whose form does not freely deform (hereinafter referred to as a box) and an article whose form freely deforms (hereinafter referred to as a flexible object) are included. included. Cargo handling includes various tasks for moving goods such as unloading, loading, sorting, and the like.

(First Embodiment)
FIG. 1 is a block diagram of a cargo handling device 1 including a control device 2 according to the present embodiment. The cargo handling device 1 is one of the devices constituting a distribution system operating in, for example, a distribution center, and performs various processes necessary for cargo handling. In the example shown in FIG. 1, the cargo handling robot 3 is applied as the article moving mechanism in the cargo handling device 1.

The cargo handling device 1 includes a control device 2, a cargo handling robot 3, a detection unit 4, and a notification unit 5.
The cargo handling robot 3 is a device that performs actual cargo handling work in the cargo handling device 1, picks articles from the accumulation area, and moves them to the destination area. The accumulation area is, for example, an area in which various unloaded articles are temporarily accumulated before being transported to the next step. The articles in the accumulation area may be arranged in an orderly manner, may be piled up in bulk, or may be placed individually one by one. The destination area is, for example, an area for transporting an article to a sorting process, an assembly process, or the like. The accumulation area and the destination area are, for example, fixtures for accommodating articles such as boxes, cages, and shelves, conveyors such as belt conveyors and roller conveyors, and transport devices such as trolleys, and workbenches for sorting and assembling.

The cargo handling robot 3 includes, for example, a grip portion 31, an arm portion 32, and a grip state detection unit 33, and the arm portion 32 operates (displaces) together with the grip portion 31 to move the article from the accumulation region to the destination region. It is a so-called robot arm to move. However, the cargo handling robot 3 can be a scalar robot (horizontal articulated robot), an XYZ stage, a linear actuator, or a combination thereof, and has a movable range according to the moving range of the article. Should be applied.

The grip portion 31 is detachably attached to the tip of the arm portion 32 (arm tip portion), and has a grip mechanism for gripping the article so as to be releasable. Gripping is defined as a concept that includes all aspects of holding an article, such as suction by a suction mechanism, pinching or gripping by a plurality of fingers or claws, and a combination thereof. The gripping mechanism of the gripping portion 31 grips the article from the accumulation area and releases the gripped article in the destination region.

The arm portion 32 is connected and extended by at least one joint portion. The arm portion 32 is subdivided into a plurality of parts by the joint portion, and each portion rotates around a predetermined axis (joint axis) at the joint portion by a servomotor or the like. As a result, the arm portion 32 operates together with the grip portion 31 by rotating each joint portion together with the grip portion 31 around the joint axis. The operation here is to take a desired posture with respect to a predetermined reference surface (for example, the floor surface of a building of a distribution center) and freely displace within a predetermined range. The predetermined range (that is, the movable range) includes the accumulation area and the destination area of the article. Therefore, by rotating each portion of the arm portion 32 around the joint axis at an arbitrary angular velocity or angular acceleration, the arm portion 32 can be displaced with respect to the integrated region and the destination region. The number of joints and joint axes may be arbitrarily set according to the operating accuracy and movable range required for the arm 32.

The gripping state detection unit 33 detects the gripping state of the article in the gripping unit 31. For example, a pressure sensor that measures the suction pressure (vacuum pressure) of an article in the suction mechanism, a flow sensor that measures the flow rate of air supplied by the suction mechanism, a force sensor that measures the tactile sensation (torque) of a plurality of fingers or claws, An optical sensor that measures the distance between the grip portion 31 and the article, an acceleration sensor that measures the acceleration of the grip portion 31, and the like can be applied as the grip state detection unit 33. Alternatively, these sensors may be combined to form the gripping state detection unit 33. The detection result of the gripping state detection unit 33, that is, the data of the gripping state of the article gripped by the gripping unit 31, is given to the control device 2.

The detection unit 4 detects various information (data) necessary for operating the cargo handling robot 3 in order to grip and move the article. The detection unit 4 has a first detection unit 41 and a second detection unit 42.

The first detection unit 41 detects the accumulation mode of the articles in the accumulation region, the release mode of the articles in the destination region, and the situation around the flow line of the cargo handling robot 3 when moving the articles from the accumulation region to the destination region. .. The stacking mode and the releasing mode of the articles are, for example, the positions, contours, sizes, orientations, postures, overlaps, boundaries, materials, and the like of the stacked or released articles. The situation around the flow line of the cargo handling robot 3 (in short, the arm portion 32) is around the flow line that hinders the securing of the flow line, such as workers, other articles, other cargo handling robots, trolleys, workbenches, walls, pillars, etc. The situation is the presence or absence of obstacles and the advancement and retreat.

As the first detection unit 41, for example, a 3D camera, a parallax camera, a plurality of 2D cameras, a spectroscopic camera, an optical sensor, or a combination thereof can be applied. These cameras are arranged at predetermined positions where the integrated area, the moving destination area, and the periphery of the flow line are within the angle of view and can be focused. For example, these cameras can be arranged at arbitrary positions such as a frame that divides an accumulation area or a destination area, or a ceiling or a wall surface of a distribution center building. In addition to the camera, the first detection unit 41 oscillates and irradiates the laser beam, and also detects the pressure of the laser range finder that detects the laser beam that bounces off the object, the floor surface of the distribution center building, and the like. Sensors and the like are also applicable.

The first detection unit 41 analyzes the detection result (as an example, the captured image data), and analyzes the accumulation mode and release mode of the articles, and the flow line peripheral situation of the cargo handling robot 3, respectively. Specifically, information or movement for analyzing the image data showing these and identifying attributes such as the position, contour, size, orientation, posture, overlap, boundary, and material of each accumulated or released article. Information for identifying the presence / absence of obstacles around the line, advancement / retreat, etc. is output to the control device 2 as analysis data. The analysis of such a detection result may be performed by the control device 2 instead of the first detection unit 41.

The situation around the flow line of the cargo handling robot 3 is analyzed by dividing the area into a caution area and a dangerous area according to the possibility of contact with an obstacle. For example, the attention area is an area where the obstacle does not come into contact with the arm portion 32 but may come into contact with the gripped article. The danger zone is a region where there is a high risk that an obstacle will come into contact with the arm portion 32, in short, a movable range of the arm portion 32. The caution area and the danger area may be a fixed range, or may be a variable range according to the size of the gripped article, the flow line of the cargo handling robot 3, and the like.

The second detection unit 42 detects the gripping state of the article gripped by the gripping unit 31. In other words, the second detection unit 42 detects the gripping state of the article in the gripping unit 31 from the appearance. That is, the second detection unit 42 and the gripping state detecting unit 33 complement each other with the detection accuracy of the gripping state of the article. The second detection unit 42 detects the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 as the gripping state of the article.

As the second detection unit 42, for example, a 3D camera, a parallax camera, a plurality of 2D cameras, a laser range finder, or a combination thereof can be applied. These are arranged in a predetermined position where the article can be captured while the article gripped by the grip portion 31 moves. For example, the second detection unit 42 can be arranged at an arbitrary position such as the ceiling or the wall surface of the building of the distribution center.

The second detection unit 42 analyzes the detection result (as an example, the captured image data) and analyzes the gripping state of the article. Specifically, the image data showing these is analyzed, and the information for specifying the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 is output to the control device 2 as analysis data. The analysis of such a detection result may be performed by the control device 2 instead of the second detection unit 42.

When a predetermined notification state occurs, the notification unit 5 notifies the surrounding workers to that effect. The predetermined notification state is, for example, a state in which an obstacle that hinders the securing of the flow line of the cargo handling robot 3 exists, a state in which an obstacle is predicted to enter the vicinity of the flow line, and the like. As the notification unit 5, a warning light, a monitor, a speaker, or a combination thereof can be applied. When an obstacle is predicted to enter, the notification unit 5 turns on (blinks) a warning light, sounds a warning sound, plays or displays a warning message, irradiates a laser, or the like, thereby causing an obstacle to the operator. Thoroughly inform and call attention to the entry of objects. For example, when an obstacle enters the caution area, the notification unit 5 only notifies (blinks) the warning light, sounds the warning sound, reproduces and displays the warning message, and irradiates the laser. On the other hand, when an obstacle enters the dangerous area, in addition to the notification by the notification unit 5, the motion plan correction means 22 formulates a motion plan (reform of the motion plan) as described later.

The control device 2 functions as a control unit in the cargo handling device 1, and controls the operations of the detection unit 4 and the notification unit 5 in addition to the cargo handling robot 3 which is an article moving mechanism. The control device 2 includes a CPU, a memory, a storage device (storage means 24 described later), an input / output circuit, a timer, and the like, and executes predetermined arithmetic processing. For example, the control device 2 reads various data by the input / output circuit, performs arithmetic processing by the CPU using the program read from the storage device into the memory, and based on the processing result, the cargo handling robot 3, the detection unit 4, and the notification unit 5 Operate control. The control device 2 is connected to the cargo handling robot 3, the detection unit 4, and the notification unit 5 by wire or wirelessly, and sends and receives various data and calculation results to and from these in operation control.

The control device 2 includes an operation planning means 21, an operation plan correcting means 22, a control means 23, and a storage means 24. In the present embodiment, as an example, the motion planning means 21, the motion planning correction means 22, and the control means 23 are configured as a program for executing a predetermined arithmetic process in the control device 2, and are stored in the storage means 24. Read to memory. The program as each of these means may be stored in the cloud, and the control device 2 may be appropriately communicated with the cloud so that the desired program can be used. In this case, the control device 2 is configured to include a communication module with the cloud and the like. Alternatively, the storage means 24 may be configured on the cloud rather than as part of the control device 2.

The motion planning means 21 formulates an motion plan for the cargo handling robot 3. The motion plan is formulated by setting the data of the waypoints of the cargo handling robot 3 when the goods are moved (hereinafter referred to as the waypoint data). In the present embodiment, the waypoint data is a set (data group) of data indicating the operation mode of the cargo handling robot 3, specifically, the operation mode of each joint portion of the arm portion 32, and is a set of data (data group) when the joint portion operates. Includes transit points, transit times of transit points, angles, angular velocities, and angular acceleration data. However, the angular acceleration can be omitted.

The waypoints are points on the flow line through which a predetermined reference point of the arm portion 32 passes when the cargo handling robot 3 operates to move the article, and are a plurality of points including the start point and the end point of the flow line. The reference point is an arbitrary point set for specifying the displacement of the arm portion 32 during operation, such as the tip center point. The loci connecting the adjacent waypoints on the flow line are the trajectories in which the reference point of the arm portion 32 is displaced along the flow line. The orbit corresponds to each section in which the flow line is divided. The trajectory is set so that the operating load of the joint portion of the arm portion 32 is as small as possible (the operating load is kept to a minimum). Therefore, the trajectory, in other words, the motion line, is set in the joint coordinate system of the arm portion 32 based on the inverse kinematics, and may coincide with the trajectory connecting the waypoints linearly at the shortest distance. It may be different.

The passing time of the waypoint is, for example, the arrival time at the waypoint near the start point (entrance side waypoint) of the orbit corresponding to the reference point of the arm portion 32, and the arrival time at the waypoint near the end point (exit side waypoint). It is the time. The time difference between the passing time of the exit side transit point and the passing time of the entrance side transit point is the time when the reference point of the cargo handling robot 3, specifically the arm portion 32, is displaced in each orbit, that is, while the reference point is displaced. It is time for each joint portion of the arm portion 32 to operate. The angle is an angle (rotation angle) at which the joint portion rotates around the joint axis when the joint portion is operated in a trajectory. The angular velocity is the rotation speed with respect to the rotation angle, and the angular acceleration is the rotation acceleration with respect to the rotation angle (time derivative of the rotation speed).

FIG. 2 shows, as an example of waypoint data, the time variation of the operating angle in a predetermined joint portion (joint portion 1) of the arm portion 32. In the example shown in FIG. 2, n + 1 waypoints P0 to Pn are set on the flow line (only 7 waypoints are shown on the drawing). The waypoint P0 is the start point of the flow line of the reference point of the arm portion 32, and the waypoint Pn is the end point of the flow line. N + orbits R1 to Rn are set by connecting adjacent n + 1 waypoints. The joint portion 1 operates each of these n orbits at a set time (T) at a set angle. The operating time of each of the orbits R1 to Rn of the joint portion 1 is indicated by (tn)-(tn-1) (n is a natural number).

The motion planning means 21 has a trajectory setting unit 211, an interference check unit 212, a passing time setting unit 213, and an operation plan formulation unit 214 in order to set waypoint data and formulate an operation plan.

The trajectory setting unit 211 sets the trajectory of the reference point of the arm unit 32. Specifically, the orbit setting unit 211 sets a waypoint of the reference point, and sets the orbit according to the waypoint. As a result, a flow line of the reference point of the arm portion 32 (hereinafter, simply referred to as a flow line) is tentatively generated.

The interference check unit 212 determines whether or not the trajectory set by the track setting unit 211 can actually be set. In the determination, the interference check unit 212 acquires data on the situation around the flow line of the cargo handling robot 3 detected and analyzed by the first detection unit 41, for example, analysis data such as the presence / absence of obstacles around the flow line and advancing / retreating. Based on the acquired analysis data, the interference check unit 212 determines whether or not the trajectory can be set. For example, if there is no obstacle around the flow line, if the obstacle can be avoided even if there is an obstacle, or if it can be predicted that the obstacle will evacuate from around the flow line, interference will occur. The check unit 212 determines that the trajectory can be set. On the other hand, for example, when an obstacle exists around the flow line and evacuation from the vicinity of the flow line cannot be predicted, the interference check unit 212 determines that the trajectory cannot be set. In this case, the track setting unit 211 resets the track, and the interference check unit 212 determines whether or not the reset track can be set. By repeating these steps, the trajectory setting unit 211 sets the trajectory that can be actually set without being interfered by obstacles.

The passing time setting unit 213 sets the time (passing time) at which the reference point of the arm unit 32 passes through each waypoint set by the track setting unit 211. The passing time setting unit 213 may set the displacement time of the reference point in the orbit in place of or in addition to the passing time. The displacement time is the elapsed time (passing time difference) from when the reference point reaches the waypoint on the inlet side of the orbit to when it reaches the waypoint on the exit side.

The operation plan formulation unit 214 sets an angle, an angular velocity, and an angular acceleration for rotating each joint portion of the arm portion 32 around the joint axis at the passage time of the transit point set by the passage time setting unit 213. Then, the motion planning unit 214 sets the passage time of the reference point of the arm unit 32 set by the trajectory setting unit 211, the passage time of the passage point set by the passage time setting unit 213, and the angle at the passage point of each joint portion. , Angular velocity, and angular acceleration are linked to set waypoint data, and an operation plan for the cargo handling robot 3 is formulated. The motion planning unit 214 sets the waypoint data for each joint part (joint part 1 to joint part X) of the arm part 32, and stores and stores the table (waypoint data table TB1) in the storage means 24.

FIG. 3 shows a storage image of waypoint data as a table (waypoint data table TB1). As shown in FIG. 3, the waypoint data is stored for each joint part of the arm part 32 (joint part 1 to joint part X) by associating the passing time, angle, angular velocity, and angular acceleration of the waypoint with each other. For example, it is managed in chronological order. In the present embodiment, the angular acceleration is included in the waypoint data, but when the waypoint data does not include the angular acceleration, the item of the angular acceleration can be omitted in the waypoint data table TB1 shown in FIG. ..

The motion plan correction means 22 formulates a motion plan for the cargo handling robot 3 when there is a factor (hereinafter referred to as an event) that hinders the movement of each joint of the arm portion 32, that is, the movement line. .. The modified motion plan is a new motion plan of the cargo handling robot 3 which is a revision and re-formulation of the motion plan formulated by the motion planning means 21. Specifically, among the waypoint data of the motion plan formulated by the motion planning means 21, the motion plan correcting means 22 corrects the passing time, the angular velocity, and the angular acceleration, respectively. Factors that hinder the movement of each joint of the arm portion 32 in the orbit, and the presence or absence thereof will be described later.

The operation plan correction means 22 has a passage time correction unit 221 and a correction operation plan formulation unit 222 in order to correct the waypoint data (in other words, the operation plan) and formulate the correction operation plan.

The passing time correction unit 221 resets the passing time by delaying or advancing the passing time of each set waypoint. When the displacement time of the reference point in the orbit is set by the passage time setting unit 213 of the operation planning means 21, the passage time correction unit 221 extends or shortens the set displacement time and re-displaces the displacement time. It may be set.

The correction operation plan formulation unit 222 rotates each joint part of the arm part 32 around the joint axis at the passage time (that is, the set correction passage time) of the waypoint reset by the passage time correction unit 221. Reset the angular acceleration respectively. Then, the correction operation plan formulation unit 222 has the passage time of the passage point set by the trajectory setting unit 211 and the passage point of each joint portion reset by the passage time correction unit 221, and the angular velocity and angle at the reset passage point. The waypoint data is corrected and set again in association with the acceleration, and the motion plan of the cargo handling robot 3 is re-formulated, that is, the modified motion plan is formulated. That is, the modified motion plan formulation unit 222 maintains the transit point (in other words, the trajectory) and the angle of the transit point data set by the motion plan formulation unit 214 as they are without modifying them, and the passing time, the angular velocity, and the angular acceleration. Fix only each. The modified motion planning unit 222 resets the passing time, angular velocity, and angular acceleration of the modified waypoint data for each joint portion of the arm portion 32, and stores and stores the modified way point data in a storage means described later. If the waypoint data does not include the angular acceleration, the resetting of the angular acceleration is omitted.

Here, an example of modifying the waypoint data of such an operation plan will be described with reference to FIGS. 4 and 5. FIG. 4 shows an aspect before the correction of the waypoint data, that is, as an example of the waypoint data set in the motion plan, the time variation before the correction of the motion angle in the predetermined joint portion (joint portion 1) of the arm portion 32. Is shown. FIG. 5 shows an aspect after the correction of the waypoint data, that is, as an example of the correction of the waypoint data set in the motion plan, after the motion angle of the predetermined joint portion (joint portion 1) of the arm portion 32 is modified. Shows time fluctuations.

As in the example shown in FIG. 4, when an event occurs at time ti, the correction motion planning unit 222 adds the position of the reference point of the arm unit 32 at that time ti as the waypoint Pi. Further, the modified motion planning unit 222 adds the angle, the angular velocity, and the angular acceleration of the joint portion 1 at the time ti to the waypoint data. The passing time correction unit 221 sets the amount of change in the passing time of the passing point (the operating time of the joint portion 1 between the passing points) after the time ti. In the examples shown in FIGS. 4 and 5, the operation time between adjacent waypoints is set to be doubled, and the total operation time of the joint portion 1 from the waypoint Pi to the waypoint Pend is doubled. There is. In FIGS. 4 and 5, black dots indicate transit points before modification, and white dots indicate transit points after modification. The waypoint P0 is the start point of the flow line, and the waypoint Pend is the end point of the flow line. In this case, the operation time of the joint portion 1 between the adjacent transit points before the correction, that is, the passing time difference (δtm) between the adjacent transit points is calculated by δtm = (tm) − (tm-1) (m). Is any natural number). Therefore, the corrected transit time (Tm-1, Tm) of the transit points Pm-1, Pm is Tm = () between the adjacent transit points Pm-1 and the transit time difference (δtm) of the transit points Pm. It has a relationship of Tm-1) + 2 × (δtm).

Based on this, the correction operation plan formulation unit 222 corrects the waypoint data by the following processing. The modified motion planning unit 222 formulates the following mathematical formula (1) as the relationship between the angle of the waypoint data after the time ti and the passing time.

The mathematical formula (1) is an Nth-order polynomial in which the angle of the waypoint data is functionalized by time (passing time of the waypoint). F (t) in the mathematical formula (1) is a locus shown by a solid line in FIG. Here, N is calculated from the number of transit points after the time ti and the number of data obtained as a boundary condition. For example, the degree N of the equation (1) is N = k + 4-1 = k + 3 from the time ti and the angular velocity and the angular acceleration at the end of the operation when the number of transit points after the time ti is k.

Next, the modified motion planning unit 222 obtains the following mathematical formulas (2) and (3). The equation (2) is a relational expression of the angular velocity obtained by differentiating the equation (1) with respect to time t. The equation (3) is a relational expression of the angular acceleration obtained by differentiating the equation (2) with respect to time t.

Next, the modified motion planning unit 222 formulates the following formulas (4), (5), and (6) for the formulas (1), (2), and (3) with the waypoint data as the boundary condition, and the coefficients. Obtain a0 to an.

Then, the modified motion planning unit 222 calculates the modified angular velocity and angular acceleration at each waypoint using the mathematical formulas (1), (2), and (3) in which the obtained coefficients a0 to an are substituted.

Instead of the method of modifying the waypoint data of the motion plan, for example, the position, speed, and acceleration of the grip portion 31 in the Cartesian coordinate system are obtained by forward kinematics, and the above-mentioned calculations are performed in the Cartesian coordinate system. May be good. After the calculation, the position, speed, and acceleration of the grip portion 31 after the movement change may be converted into the angular velocity and the angular acceleration of the joint portion of the arm portion 32 by inverse kinematics.

The control means 23 includes an arm control unit 231, a grip control unit 232, and an event determination unit 233.

The arm control unit 231 operates (rotates) each joint portion of the arm portion 32 according to either the motion plan formulated by the motion plan formulation unit 214 or the modified motion plan formulated by the modified motion plan formulation unit 222. Specifically, the arm control unit 231 drives a servomotor to rotate each joint unit at an angle, an angular velocity, and an angular acceleration set around the joint axis. At that time, if the event presence / absence condition described later is not satisfied, the arm control unit 231 rotates each joint portion of the arm portion 32 at the angle, the angular velocity, and the angular acceleration set in the motion plan. As a result, the arm unit 32 operates in the orbit with the difference (operation time) of the passing time set in the operation plan. On the other hand, when the event presence / absence condition is satisfied, the arm control unit 231 rotates each joint portion of the arm portion 32 at the angle set in the motion plan, the angular velocity modified by the modified motion plan, and the angular acceleration. As a result, the arm unit 32 operates in the orbit with the difference in the passing time modified by the modified motion plan (corrected operation time). That is, the arm control unit 231 operates the cargo handling robot 3 from the start point to the end point of the flow line based on the presence or absence of a factor (event) that hinders the proper operation of the cargo handling robot 3 in the orbit.

The grip control unit 232 controls the operation of the grip mechanism of the grip unit 31, grips the article, and releases the gripped article. At that time, the article to be gripped is selected based on the attribute (accumulation mode) of the article in the integrated region detected and analyzed by the first detection unit 41, and the target position (target gripping position) for gripping the selected article. Set the gripping mode such as suction pressure and holding pressure.

The grip control unit 232 identifies a selected article from the article group based on a predetermined selection criterion corresponding to the analysis data acquired from the first detection unit 41. The selection criteria are, for example, the height position in the article group, the distance from the cargo handling robot 3, the gap with other articles, the position in the accumulation area, the material of the article (including the packing state and the packaging state), and the like. Specifically, the one at the highest position in the article group, the one closest to the cargo handling robot 3, the one farthest from other articles, the one near the center of the accumulation area, and the grip (adsorption). ) The grip control unit 232 specifies an article having a predetermined material as an article that is easy to be selected. Alternatively, the grip control unit 232 may specify the selected article using these as a composite selection criterion.

Further, the grip control unit 232 controls the gripping force of the article by supplying and discharging air for generating the suction pressure (vacuum pressure) of the suction mechanism, adjusting the tension angle of the finger joint and the nail joint, and the like. Further, based on the attribute (release mode) of the article in the movement destination area detected by the first detection unit 41, a target position (target release position) for releasing the grasped article, a placement area after release, and the like are set. do. For example, the release force (reduction of gripping force) of the article is controlled by releasing the suction mechanism that adsorbs the article to the atmosphere, adjusting the relaxation angle of the finger joint and the nail joint, and the like.

In this way, the gripping control unit 232 formulates a gripping plan for the article and controls the operation of the gripping mechanism of the gripping unit 31 according to the gripping plan. In formulating the gripping plan, the gripping control unit 232 sets various parameters as described above in order to control the operation of the gripping mechanism in order to grip and release the article.

The event determination unit 233 determines the event existence / non-existence condition. The event presence / absence condition is a condition for determining whether or not a factor (event) that hinders the movement of each joint portion of the cargo handling robot 3, specifically, the arm portion 32, has occurred. In determining the event presence / absence condition, the event determination unit 233 acquires, for example, data on the flow line surroundings of the cargo handling robot 3 detected and analyzed by the first detection unit 41. Based on the acquired data, the event determination unit 233 determines whether or not there is an obstacle that hinders the securing of the flow line of the cargo handling robot 3, and whether or not an obstacle is predicted to enter the vicinity of the flow line. Whether or not the event exists is determined. Hereinafter, such determination of the presence / absence of an event is appropriately referred to as a determination of the presence / absence of the first event.

In place of or in addition to the data on the flow line peripheral situation of the cargo handling robot 3, the event determination unit 233 has data on the gripping state of the article gripped by the gripping unit 31 detected and analyzed by the second detecting unit 42, and the gripping state. Data of the gripping state of the article detected by the detection unit 33 may be acquired. Based on the acquired data on the gripping state of the article, the event determination unit 233 determines, for example, whether or not the vibration, deformation, posture, tilt, etc. of the article gripped by the gripping section 31 are within the allowable range as the presence or absence of the event. .. Specifically, it occurs in an article gripped by changing the angular velocity and angular acceleration of each joint portion of the arm portion 32 with the design allowable gripping force (suction pressure, pinching pressure, etc.) of the grip portion 31 as the upper limit. It is possible to determine whether or not the inertial force is approaching the allowable gripping force. In addition, the measured values of the pressure sensor that measures the suction pressure (vacuum pressure) of the article and the force sensor that measures the tactile sensation (torque) of a plurality of fingers and claws are not appropriate values, and the article falls off from the grip portion 31. It is possible to determine whether or not there is a risk. Alternatively, it is possible to determine whether or not the article gripped by the grip portion 31 is deformed or vibrates beyond an allowable range. Hereinafter, such determination of the presence / absence of an event is appropriately referred to as a determination of the presence / absence of a second event.

Regardless of which determination is made as the event presence / absence condition, the event determination unit 233 assigns the determination result to the motion plan correction means 22 (passing time correction unit 221 and correction operation plan formulation unit 222) and the notification unit 5. do.

Further, when the event existence / non-existence condition (first event existence / non-existence condition, second event existence / non-existence condition) is satisfied, the event determination unit 233 determines the operation plan correction condition. The motion plan modification condition is a condition for determining whether or not it is necessary to modify the motion plan. In determining the motion planning correction condition, the event determination unit 233 acquires, for example, the flow line peripheral situation data of the cargo handling robot 3 detected and analyzed by the first detection unit 41. Further, for example, the event determination unit 233 acquires data on the gripping state of the article detected and analyzed by the second detection unit 42 and data on the gripping state of the article detected by the gripping state detecting unit 33. The determination of the motion plan correction condition will be described in detail in the description of the control flow of event processing described later. The event determination unit 233 assigns the determination result of the operation plan correction condition to the operation plan correction means 22 (passing time correction unit 221 and correction operation plan formulation unit 222) and the notification unit 5.

Regarding the operation of the cargo handling device 1 having such a configuration, specifically, the process of moving the article from the accumulation area to the destination area (hereinafter referred to as the article movement process), the cargo handling robot 3, the detection unit 4, and the notification unit 5 This will be described according to the control flow of the control device 2. 6 and 7 show a control flow of the control device 2 for the cargo handling robot 3, the detection unit 4, and the notification unit 5 in the article movement process.

When the article movement process is started, the cargo handling robot 3 is in the initial state. The initial state of the cargo handling robot 3 is a state in which the arm portion 32 is positioned at the reference position. The reference position is, for example, a position where the arm portion 32 does not interfere with either the accumulation area or the movement destination area of the article.

In moving the article from the accumulation area to the destination area, the control device 2 causes the detection unit 4 to detect various information necessary for the article movement process (S101). Here, the first detection unit 41 detects the accumulation mode, the release mode, and the situation around the flow line of the cargo handling robot 3 and analyzes the detection result. The first detection unit 41 attaches the analysis data to the control means 23.

When the analysis data is given, the gripping control unit 232 of the control means 23 formulates a gripping plan for the article (S102). As a result, the selected article, the target gripping position, the gripping mode (suction pressure, holding pressure, etc.), the target release position, and the like are set as the gripping plan.

Further, when the analysis data is given, the motion planning means 21 formulates an motion plan for the cargo handling robot 3 (S103). Specifically, the trajectory setting unit 211 sets a waypoint of the reference point of the arm unit 32, and sets the trajectory according to the waypoint. The passing time setting unit 213 sets the passing time of the reference point of the arm unit 32 at each waypoint set by the track setting unit 211. The operation plan formulation unit 214 sets an angle, an angular velocity, and an angular acceleration for rotating each joint portion of the arm portion 32 around the joint axis at the passage time set by the passage time setting unit 213. The motion planning unit 214 stores and stores the waypoint data set for each joint portion of the arm portion 32 in the storage means 24 (see FIG. 3).

When the motion plan is formulated, the arm control unit 231 of the control means 23 operates (rotates) each joint portion of the arm unit 32 according to the motion plan (S104). As a result, the grip portion 31 is displaced together with the arm portion 32.

When the gripping unit 31 reaches the target gripping position, the gripping control unit 232 grips the selected article from the integrated region (S105). The gripping control unit 232 uses, for example, the suction pressure set in the gripping plan before the reference position (for example, the tip center position) of the gripping unit 31 reaches the target gripping position. Alternatively, the holding pressure set in the gripping plan when the reference position of the gripping portion 31 reaches the target gripping position is used. As a result, the selected article can be appropriately gripped by the gripping mechanism of the gripping portion 31.

With the selected article gripped by the gripping mechanism, the arm control unit 231 continues the operation of each joint portion of the arm portion 32 according to the motion plan (S106). In other words, the arm control unit 231 displaces the reference point of the arm unit 32 toward the set final waypoint (end point of the flow line). In the event processing (S201 to S205) described later, the motion plan here is a revised motion plan (when the motion plan formulated by the motion planning means 21 is modified by the motion plan correction means 22). It becomes a correction operation plan).

Subsequently, the event determination unit 233 of the control means 23 determines the event presence / absence condition (S107). As an example, the event determination unit 233 determines the presence / absence condition of the first event. In determining the presence / absence condition of the first event, the event determination unit 233 acquires the data of the flow line peripheral situation of the cargo handling robot 3 detected and analyzed by the first detection unit 41. For example, if there is an obstacle that hinders the securing of the flow line, or if it is predicted that the obstacle will enter the vicinity of the flow line, the event determination unit 233 will satisfy the first event presence / absence condition. judge. On the other hand, for example, when there is no obstacle that hinders the securing of the flow line, or when the entry of the obstacle to the vicinity of the flow line cannot be predicted, the event determination unit 233 does not satisfy the first event presence / absence condition. Is determined.

As the event presence / absence condition, the event determination unit 233 may determine the second event presence / absence condition in place of or in addition to the first event presence / absence condition. In determining the second event determination condition, the event determination unit 233 acquires the data of the gripping state of the article detected (analyzed) by the second detection unit 42 and the gripping state detection unit 33. For example, when the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 are within the allowable range, the event determination unit 233 determines that the second event presence / absence condition is not satisfied. On the other hand, for example, when the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 are not within the permissible range, the event determination unit 233 determines that the second event presence / absence condition is satisfied.

When the event existence / non-existence condition is satisfied, the control means 23 executes a predetermined event process (S108). For example, when at least one of the first event existence / non-existence condition and the second event existence / non-existence condition is satisfied, the event processing is executed. The details of event processing will be described later.

On the other hand, when the event existence / non-existence condition is not satisfied, the arm control unit 231 determines the motion planning completion condition (S109). The motion plan completion condition is a condition for determining whether or not the motion of each joint portion of the arm portion 32 is completed according to the motion plan. The arm control unit 231 determines that the operation completion condition is satisfied when the reference point of the arm unit 32 has reached the last set waypoint (end point of the flow line), and reaches the last waypoint. If not, it is determined that the operation completion condition is not satisfied.

If the operation completion condition is not satisfied, the arm control unit 231 continues the operation of each joint portion of the arm portion 32 according to the motion plan (S106). In this case, for example, since the last waypoint (end point of the flow line) where the reference point of the arm part 32 is set has not been reached yet, the movement of each joint part of the arm part 32 is performed until the last waypoint is reached. Will be continued.

On the other hand, when the operation completion condition is satisfied, the grip control unit 232 releases the article at the target release position (S110). As a result, the movement process for the released article (selected article) is completed. At that time, the grip control unit 232 transmits a signal indicating that a series of controls (article movement processing) in the motion planning of the cargo handling robot 3 for the selected article has been normally completed to the arm control unit 231 and the motion planning means 21. Then, the control device 2 continues to perform the article moving process (S101 to S110) for moving the next article from the accumulating area to the moving destination area. That is, the control device 2 repeats predetermined control while the articles are accumulated in the accumulation area. Then, when the articles accumulated in the accumulation area are exhausted, the article movement process is terminated.

Next, the event processing (S108) executed when the event presence / absence condition is satisfied in S107 will be described. FIG. 7 shows a control flow of the control device 2 for the cargo handling robot 3, the detection unit 4, and the notification unit 5 in event processing.

In the event processing, the event determination unit 233 determines the operation plan correction condition (S201). Therefore, the event determination unit 233 acquires the data of the flow line peripheral situation of the cargo handling robot 3 detected and analyzed by the first detection unit 41. For example, if an obstacle that hinders the securing of the flow line exists in the dangerous area and the evacuation of the obstacle from the dangerous area cannot be predicted, the event determination unit 233 determines that the motion planning correction condition is satisfied. On the other hand, for example, when the obstacle does not exist in the dangerous area, or even if the obstacle exists, it can be predicted that the obstacle will evacuate from the dangerous area, the event determination unit 233 determines that the motion planning correction condition is not satisfied. .. Hereinafter, the motion plan correction condition determined in this way is referred to as a first motion plan correction condition. The event determination unit 233 may determine the motion planning correction condition by setting the requirement for the determination as a caution area instead of a danger area. As a result, for example, when the operation plan correction condition is satisfied with the requirement as the dangerous area and when the operation plan correction condition is satisfied with the requirement as the caution area, the correction content (correction degree) of the operation plan of the cargo handling robot 3 described later. It is possible to have a difference in.

In place of or in addition to the analysis data of the flow line peripheral situation of the cargo handling robot 3, the event determination unit 233 detects and analyzes the data of the gripping state of the article held by the gripping unit 31 detected and analyzed by the second detecting unit 42. Data of the gripping state of the article detected by the state detection unit 33 may be acquired. Based on the acquired data on the gripping state of the article, the event determination unit 233 determines that the motion plan correction condition is satisfied when, for example, the vibration, deformation, posture, inclination, etc. of the article gripped by the gripping section 31 exceeds the allowable range. judge. On the other hand, for example, when the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 are within the permissible range, it is determined that the motion plan correction condition is not satisfied. Hereinafter, the operation plan correction condition determined in this way is referred to as a second operation plan correction condition.

When the motion plan correction condition is satisfied, the motion plan correction means 22 correction motion plan formulation unit 222 modifies the motion plan of the cargo handling robot 3 formulated by the motion planning means 21 and formulates a motion plan (S202). For example, when at least one of the first motion plan modification condition and the second motion plan modification condition is satisfied, the operation plan is modified and the modified motion plan is formulated. Specifically, in the waypoint data of the motion plan, the passing time, the angular velocity, and the angular acceleration are corrected respectively.

Next, the arm control unit 231 operates (rotates) each joint portion of the arm portion 32 according to the modified motion plan (corrected motion plan) (S203). As a result, each joint portion of the arm portion 32 operates at the corrected angular velocity and angular acceleration at the corrected passage time.

Then, the notification unit 5 gives a predetermined notification (S204). For example, when the motion plan of the cargo handling robot 3 is modified and each joint portion of the arm portion 32 is operating according to the corrected passing time, angular velocity, and angular acceleration, the surrounding workers are notified to that effect. Such a notification has a meaning as a warning to thoroughly inform the surrounding workers that the operation mode of the cargo handling robot 3 will change in this way and to call attention to it. That is, such a notification is given so as not to hinder the surrounding workers by slowing or speeding up the angular velocity and the angular acceleration of each joint of the arm portion 32.

Further, instead of or in addition to such a notification by the notification unit 5, the operation of the cargo handling robot 3 may be stopped. For example, if the second motion plan modification condition is satisfied in S201, the article may fall off from the grip portion 31, and the operation of the cargo handling robot 3 is stopped to ensure safety for surrounding workers and articles. Can be further enhanced. When stopping the cargo handling robot 3, for example, the servomotor that rotates the joint portion may be stopped, but the same stopped state can be achieved by extending the corrected passage time of the reference point of the arm portion 32 infinitely. can.

On the other hand, when the operation plan correction condition is not satisfied in S201, the notification unit 5 similarly gives a predetermined notification (S204). For example, if there are obstacles in the attention area, if obstacles are expected to enter the attention area, or if these obstacles evacuate from the attention area, the surrounding workers are informed to that effect. Notice. Further, for example, when there is a possibility that the vibration, deformation, posture, inclination, etc. of the article gripped by the grip portion 31 may exceed the allowable range, the surrounding workers are notified to that effect. In such a notification, although there is no change in the operation mode of the cargo handling robot 3, specifically, the angular velocity and the angular acceleration of each joint portion of the arm portion 32, the fact that an obstacle has entered the attention area and the gripped article It has the meaning of informing the surrounding workers of the unstable posture of the robot and calling attention to it.

In addition, instead of or in addition to the notification to the surrounding workers as described above, the notification unit 5 may notify the upper management system of the cargo handling device 1 that the operation plan has been revised. As a result, for example, the manager of the upper management system is informed of the revision of the operation plan, and the revision of the operation plan can be reflected in the operation control of the entire distribution system including the cargo handling device 1.

As described above, according to the control device 2 of the present embodiment, the operation plan of the cargo handling robot 3 is modified according to the occurrence of the event, and after the event occurs, the cargo handling robot 3 is operated according to the modified motion plan (corrected motion plan). Can be made to. In formulating the modified motion plan, the transit points and angles of the motion plan can be maintained as they are without modification, and only the passage time, angular velocity, and angular acceleration can be modified. Therefore, since it is not necessary to reset (recalculate) the waypoint, in other words, the trajectory, the amount of calculation at the time of motion plan modification is small, and the motion plan can be modified in almost real time. If the waypoint data does not include the angular acceleration, it is not necessary to correct the angular acceleration, and it is possible to further reduce the amount of calculation at the time of correcting the motion plan.

Therefore, even when an event occurs or is predicted to occur, the operation mode (passing time, angular velocity, and angular acceleration) can be appropriately changed without stopping the cargo handling robot 3. As a result, the angular velocity and angular acceleration at the time of rotation of each joint portion of the arm portion 32 can be smoothly slowed or accelerated regardless of the occurrence of an event, and the cargo handling robot 3 can be smoothly operated. Further, since the cargo handling robot 3 can be suppressed from stopping due to the occurrence of an event, the efficiency of cargo handling work can be improved.

In the present embodiment, the control device 2 in the case where the article moving mechanism is the cargo handling robot 3 has been described, but the article moving mechanism can be applied with various mechanisms for moving the article, and is not limited to the cargo handling robot 3. For example, the article moving mechanism may be an automatic guided vehicle (AGV) that transports articles. Hereinafter, an embodiment of the control device when the article moving mechanism is an AGV will be described as a second embodiment.

(Second embodiment)
FIG. 8 is a block diagram of the automatic traveling system 100 including the control device 81 according to the present embodiment. The automatic traveling system 100 is a control system for automatically traveling a plurality of AGV8s in, for example, a distribution center. The AGV8 corresponds to an article moving mechanism in the automatic traveling system 100. In the example shown in FIG. 8, the control device 81 is mounted on the AGV8.

The automatic traveling system 100 includes a management device 7 and a plurality of AGV8s.
The management device 7 centrally manages the operation modes (running modes) of the plurality of AGV8s. The management device 7 includes a CPU, a memory, a storage device (a storage management unit 74 described later), an input / output circuit, a timer, and the like, and executes predetermined arithmetic processing. For example, the management device 7 reads various data by an input / output circuit, performs arithmetic processing on the CPU using a program read from the storage device to the memory, controls the operation of each AGV8 based on the processing result, and centrally manages them. do. The management device 7 is wirelessly connected to a plurality of AGV8s via a communication network (network) NW, and transmits / receives various data, calculation results, and the like to and from the plurality of AGVs 8 in operation control and centralized management.

The management device 7 includes an AGV management unit 71, a correction command unit 72, a communication management unit 73, and a storage management unit 74. In the present embodiment, as an example, the AGV management unit 71, the correction command unit 72, and the communication management unit 73 are configured as a program for executing a predetermined arithmetic process in the management device 7, and are stored in the storage management unit 74. Is read into memory. It should be noted that these programs may be stored in the cloud, and the management device 7 may be appropriately communicated with the cloud so that the desired program can be used. In this case, the management device 7 is configured to include a communication module with the cloud.

The AGV management unit 71 is an operation planning means for formulating an operation plan for each of the plurality of AGV8s. The motion plan is formulated by setting the waypoint data of AGV8 during running. In the present embodiment, the waypoint data is a set (data group) of data indicating the operation mode of the AGV8, specifically, the operation mode of the drive unit 83 described later, and the waypoint data when the AGV8 operates (runs). , Includes transit time, velocity, and acceleration data for waypoints. However, the acceleration can be omitted.

The waypoints are points on the flow line (running path) that the AGV8 passes through when traveling, and are a plurality of points including the start point and the end point of the flow line. The starting point of the flow line is the current position of the AGV 7 (for example, a warehouse of goods), and the data of the current position is given as estimation data by the control device 81 (specifically, the position estimation unit 8121 described later). The end point of the flow line is the destination of AGV8 (for example, the delivery place of goods). The locus connecting the adjacent waypoints on the flow line is the trajectory on which the AGV8 travels along the flow line. The orbit corresponds to each section in which the flow line is divided. The trajectory, in other words, the flow line, is set in the Cartesian coordinate system, and may or may not match the trajectory that connects the waypoints linearly at the shortest distance.

The passing time of the waypoints is the time when the AGV8 passes through each waypoint. For example, it is the arrival time at the waypoint near the start point (entrance side waypoint) and the arrival time at the waypoint near the end point (exit side waypoint). The time difference between the passing time of the exit-side transit point and the passing time of the entrance-side transit point is the time during which the AGV8 operates (travels on each orbit) in each orbit. The speed is the speed of AGV8 at each waypoint. The acceleration is the acceleration of AGV8 at each waypoint.

Regarding the waypoint data, the difference is that the speed and acceleration in the Cartesian coordinate system are dealt with instead of the angular velocity and the angular acceleration in the joint coordinate system, but the basic way of grasping the waypoint data in the present embodiment is described above. It conforms to the waypoint data in the first embodiment. Therefore, the time variation of the operating angle in the predetermined joint portion (joint portion 1) of the arm portion 32 shown in FIG. 2 can be regarded as an example of the time variation of the speed in the predetermined AGV8.

The AGV management unit 71 stores and stores the waypoint data (passage point data table TB2) of each AGV8 in the storage management unit 74 which is a storage means. It should be noted that the configuration may be such that these waypoint data are stored in the cloud and appropriately communicated with the cloud via, for example, the communication management unit 73 so that the desired waypoint data can be used. In this case, the communication management unit 73 is configured to include a communication module with the cloud. Alternatively, the storage management unit 74 may be configured on the cloud instead of as a part of the management device 7.

FIG. 9 shows a storage image of waypoint data as a table (waypoint data table TB2). As shown in FIG. 9, the waypoint data is stored for each AGV8 (AGV01 to AGV0x) by associating the passing time, speed, and acceleration of each waypoint, which will be described later, with each other, and is managed in time series, for example. ing. In the present embodiment, the acceleration is included in the waypoint data, but when the waypoint data does not include the angular acceleration, the acceleration item can be omitted in the waypoint data table TB2 shown in FIG.

The correction command unit 72 selects the AGV8 that modifies the operation plan formulated by the AGV management unit 71. That is, the operation plan formulated by the AGV management unit 71 is appropriately revised. When a factor (event) that hinders proper running of the predetermined AGV8 occurs, the correction command unit 72 performs a correction operation on the control device 81 (specifically, the correction operation plan formulation unit 811 described later) of the predetermined AGV8. Have them formulate a plan. As an event, for example, when the AGV8 cannot specify its own current position, when a worker or the like enters the driving path of the AGV8, a traffic jam or another vehicle to the driving path of the own vehicle due to a delay in the traveling of the AGV8 (own vehicle) or the like. For example, when there is a risk of intrusion. The modified motion plan is a new motion plan for the AGV8, which is a revised motion plan formulated by the AGV management unit 71. Specifically, among the waypoint data of the operation plan formulated by the AGV management unit 71, the correction command unit 72 corrects the passing time. Then, the correction command unit 72 generates a command (trigger data) instructing the AGV 8 that has selected to reset the waypoint data (correct the operation plan) based on the corrected passage time.

The communication management unit 73 transmits and receives various data and calculation results necessary for the operation of the AGV8 to and from the AGV8 (specifically, the communication unit 86 described later). For example, the communication management unit 73 transmits the operation plan (in other words, the waypoint data set by the AGV management unit 71) and the trigger data generated by the correction command unit 72 to the AGV8. Further, the communication management unit 73 receives the data of the current position and the presence / absence of occurrence of an event (determination result of the event existence / non-existence condition by the event determination unit 8123 described later) from each AGV8.

The AGV8 automatically travels and transports the article from the current position (for example, the warehouse of the article) to a desired destination (for example, the delivery place of the article) unmanned. The AGV 8 includes a control device 81, an accommodating unit 82, a driving unit 83, a detection unit 84, a storage unit 85, and a communication unit 86.

The accommodating portion 82 is a component for accommodating an article in AGV8. For example, a box or shelf provided in the vehicle body (self-propelled portion) of the AGV8, or a trolley or a car towed by the vehicle body of the AGV8 can be applied as the accommodating portion 82, and the form thereof is not particularly limited.

The drive unit 83 is a component for driving the AGV 8. For example, a power source such as a motor or an engine, a transmission, a tire, or the like is included in the drive unit 83.

The detection unit 84 detects the surrounding situation of AGV8. As the peripheral situation of the AGV8, for example, the existence situation of a worker around the traveling path of the AGV8, another AGV, a wall, a pillar, and the like. As the detection unit 84, for example, a 3D camera, a parallax camera, a plurality of 2D cameras, a laser range finder, or a combination thereof can be applied. These are arranged at predetermined positions of the AGV8 that can appropriately capture the front, rear, side, etc. of the traveling path.

The detection unit 84 analyzes the detection result (as an example, the captured image data) and analyzes the peripheral situation of the AGV8. Specifically, the image data showing these is analyzed, and the information for identifying the presence / absence of another AGV8 (hereinafter referred to as another vehicle) around the traveling path of the AGV8 is output to the control device 81 as analysis data. .. The analysis of such a detection result may be performed by the control device 81 instead of the detection unit 84. Regarding the surrounding situation of AGV8, the area may be divided into a caution area, a danger area, and the like according to the degree of possibility of contact with another vehicle and analyzed.

The storage unit 85 stores data necessary for running the AGV8. The stored data is, for example, map data including a travel path of AGV8, waypoint data of an operation plan of AGV8 described later, and the like. The storage image of the waypoint data is as shown in the waypoint data table TB2 shown in FIG. 9 described above. However, the waypoint data stored in the storage unit 85 is only the waypoint data of the own vehicle. In the present embodiment, as an example, the storage unit 85 is a separate body from the storage device of the control device 81, but may be a part of the storage device. Further, the storage unit 85 may be a cloud. In this case, the communication unit 86 may be configured to include, for example, a communication module with the cloud.

The communication unit 86 transmits and receives various data and calculation results (signals) that control the operation of the AGV8 (own vehicle) to and from the management device 7 (specifically, the communication management unit 73). For example, the communication unit 86 receives the operation plan (in other words, the waypoint data set by the AGV management unit 71) and the trigger data generated by the correction command unit 72. Further, the communication unit 86 uses the data of the current position (own vehicle position) of the AGV8 estimated by the control device 81 (specifically, the position estimation unit 8121 described later) and the determination result of the event presence / absence condition by the event determination unit 8123 described later. To send.

The control device 81 functions as a control unit in the AGV8, which is an article moving device, and controls the operation (in short, traveling) of the AGV8. The control device 81 includes a CPU, a memory, a storage device (non-volatile memory), an input / output circuit, a timer, and the like, and executes a predetermined arithmetic process. For example, the control device 81 reads various data by the input / output circuit, performs arithmetic processing by the CPU using the program read from the storage device into the memory, and based on the processing result, the AGV8, more specifically, the drive unit 83, the detection The operation of the unit 84, the storage unit 85, and the communication unit 86 is controlled.

The control device 81 includes a correction operation plan formulation unit (operation plan correction means) 811 and a control means 812.

The correction operation plan formulation unit 811 is an operation plan correction means for correcting the operation plan in the control device 81. When the management device 7 instructs the correction operation plan formulation unit 811 to correct the operation plan, or simply to reset the waypoint data, the operation plan is corrected (corrected) by resetting the waypoint data according to the instruction contents. Formulate an operation plan). Specifically, when the trigger data generated by the correction command unit 72 is received via the communication unit 86, the correction operation plan formulation unit 811 formulates the correction operation plan. In formulating the modified motion plan, the modified motion plan formulation unit 811 corrects the passing time, speed, and acceleration in the waypoint data of the motion plan formulated by the AGV management unit 71, respectively. The corrected passage time is set by the correction command unit 72 and given to the correction operation plan formulation unit 811. Therefore, the modified motion planning unit 811 resets the speed and the acceleration so that the AGV8 passes through the waypoint at the assigned passing time. The method for resetting the velocity and acceleration is based on the method for calculating the corrected angular velocity and angular acceleration at each waypoint of the waypoint data in the first embodiment described above.

Then, the correction operation plan formulation unit 811 sets the passing time of the waypoint of the AGV8 (own vehicle) set by the AGV management unit 71 and the waypoint of the AGV8 reset by the correction command unit 72, and the reset waypoint. By associating the speed and acceleration of the AGV8 in the above, the waypoint data is corrected and set again, and the operation plan of the AGV8 is re-established, that is, the modified operation plan is formulated. That is, the correction operation plan formulation unit 811 maintains the waypoint (in other words, the trajectory) of the waypoint data set by the AGV management unit 71 as it is without correcting it, and the passage time reset by the correction command unit 72. Only the velocity and acceleration are modified according to. The modified motion planning unit 811 stores the modified waypoint data in the storage unit 85 and stores it. If the waypoint data does not include acceleration, the correction of acceleration is omitted.

The control means 812 automatically drives the AGV8 from the current position (for example, the warehouse of the article) to the desired destination (for example, the delivery place of the article). The control means 812 has a position estimation unit 8121, a travel control unit 8122, and an event determination unit 8123.

The position estimation unit 8121 estimates the current position of the AGV8. The current position is the current position of the own vehicle of the AGV8, which is the traveling position of the own vehicle when the vehicle is running and the stop position of the own vehicle when the vehicle is stopped. In the estimation, the position estimation unit 8121 collates, for example, the analysis data with the map data based on the analysis data of the detection unit 84 and the map data stored in the storage unit 85.

The travel control unit 8122 operates (travels) the AGV 8 according to the operation plan stored in the storage unit 85. The motion plan here is a revised motion plan (corrected motion plan) when the motion plan formulated by the AGV management unit 71 is modified by the modified motion plan formulation unit 811. According to such an operation plan, the travel control unit 8122 causes the AGV8 to travel along the flow line (travel path) at the speed and acceleration set in the waypoint data. At that time, the traveling control unit 8122 adjusts the output of the power source of the drive unit 83 so as to have a set speed and acceleration, and drives the tire while appropriately shifting the gear with the transmission.

The event determination unit 8123 determines the event existence / non-existence condition. The event presence / absence condition is a condition for determining whether or not an event as described above has occurred. In determining the event presence / absence condition, the event determination unit 8123 acquires, for example, the data of the peripheral situation of the AGV8 detected and analyzed by the detection unit 84, and the data of the current position of the AGV8 estimated by the position estimation unit 8121. Based on the acquired data, the event determination unit 8123 determines, for example, whether or not the AGV8 can specify its own current position, whether or not a worker or the like has entered the travel path of the AGV8, and whether or not the AGV8 (own vehicle) travels. Whether or not there is a risk of traffic congestion or another vehicle entering the own vehicle's driving path due to delay or the like is determined as the presence or absence of the event. The event determination unit 8123 assigns the determination result to the correction command unit 72 via the communication unit 86 and the communication management unit 73.

The process of traveling the AGV 8 having such a configuration from the current position to the destination (hereinafter referred to as travel process) will be described according to the control flow of the control device 81 and the management device 7 for the AGV 8. FIG. 10 shows a control flow of the control device 81 and the management device 7 for the AGV 8 in the traveling process.

The state (initial position) of each AGV8 at the time of starting the traveling process is not particularly limited. For example, all the vehicles may be parked in the warehouse of goods, or each car is dispersed in the warehouse of goods, the delivery place, and the like. You may have.

In the traveling process, the management device 7 formulates an operation plan for each AGV8 (S301). Therefore, the AGV management unit 71 sets the waypoint data of the operation plan. As the waypoint data, the AGV management unit 71 sets the current position and destination of each AGV8, and sets the waypoint between them. Further, the AGV management unit 71 sets the passing time, speed, and acceleration of the waypoints, respectively.

When the motion plan is formulated, the management device 7 transmits the motion plan to the corresponding AGV 8 (S302). As a result, the waypoint data of the operation plan is given to each AGV8. The waypoint data is stored in the storage unit 85 of the AGV8.

When the motion plan is transmitted and the waypoint data is added, the AGV8 operates (runs) according to the motion plan (S303). Specifically, the travel control unit 8122 of the control device 81 drives the drive unit 83, and the AGV 8 is flowed (travel path) at the speed and acceleration set in the waypoint data according to the operation plan read from the storage unit 85. Run along.

Subsequently, the event determination unit 8123 of the control device 81 determines the event presence / absence condition (S304). In determining the event presence / absence condition, the event determination unit 8123 acquires the data of the peripheral situation of the AGV8 detected and analyzed by the detection unit 84 and the data of the current position of the AGV8 estimated by the position estimation unit 8121. For example, when the AGV8 cannot specify its own current position, when a worker or the like has entered the driving path of the AGV8, a traffic jam or another vehicle to the driving path of the own vehicle due to a delay in the traveling of the AGV8 (own vehicle) or the like. If there is a risk of intrusion, the event determination unit 8123 determines that the event existence / non-existence condition is satisfied. On the other hand, for example, when the AGV8 can specify its own current position, when a worker or the like has not entered the driving path of the AGV8, a traffic jam or another vehicle to the own vehicle driving path due to a running delay of the AGV8 (own vehicle) or the like. If there is no possibility that the event will enter, the event determination unit 8123 determines that the event existence / non-existence condition is not satisfied. The event determination unit 8123 assigns the determination result of the event presence / absence condition to the correction command unit 72 of the management device 7 via the communication unit 86.

When the event existence / non-existence condition is satisfied, the correction command unit 72 generates a correction command for the operation plan formulated by the AGV management unit 71 (S305). The correction command is a command (trigger data) instructing the AGV8 to reset the waypoint data and formulate the correction operation plan. The correction command unit 72 corrects the passing time of the waypoint data of the operation plan formulated by the AGV management unit 71, and generates a correction command including the corrected passing time. The correction command unit 72 assigns the generated correction command to the correction operation plan formulation unit 811 of the control device 81 via the communication management unit 73.

The correction operation plan formulation unit 811 determines whether or not there is a correction command (S306).
When the correction command is given from the correction command unit 72, the correction operation plan formulation unit 811 corrects the operation plan (S307). In the correction, the correction operation plan formulation unit 811 reads the waypoint data of the operation plan from the storage unit 85, and corrects the passage time to the passage time given by the correction command unit 72. Then, the speed and the acceleration are set again so that the AGV8 passes through the waypoint at the corrected passing time, and the operation plan of the AGV8 is re-formulated (corrected operation plan is formulated). The modified motion planning unit 811 stores the modified waypoint data in the storage unit 85 and stores it.

Then, the AGV8 continues the operation (running) according to the operation plan (S308). The operation plan here is an operation plan (corrected operation plan) in which the operation plan formulated by the AGV management unit 71 is modified by the modified operation plan formulation unit 811. That is, the travel control unit 8122 continuously travels the AGV 8 along the flow line (travel path) at the reset speed and acceleration.

If the event presence / absence condition is not satisfied in S304, or if the correction command is not given from the correction command unit 72 in S306, the AGV8 similarly continues the operation (running) according to the operation plan (S308). In this case, the motion plan formulated by the AGV management unit 71 has not been modified, and the corresponding waypoint data is stored in the storage unit 85 without being reset. Therefore, as the operation plan here, the operation plan formulated by the AGV management unit 71 is applied as it is. That is, the travel control unit 8122 continuously travels the AGV 8 along the flow line (travel path) at the speed and acceleration set by the AGV management unit 71.

During the traveling of the AGV8, the traveling control unit 8122 determines the operation planning completion condition (S309). The operation plan completion condition is a condition for determining whether or not the operation (running) of the AGV 8 is completed according to the operation plan. The travel control unit 8122 determines that the operation completion condition is satisfied when the destination of the AGV8 is reached, for example, the last waypoint (end point of the flow line) in which the AGV8 is set, and reaches the last waypoint. If not, it is determined that the operation completion condition is not satisfied.

If the operation completion condition is not satisfied, the travel control unit 8122 continuously drives the AGV 8 according to the operation plan. In this case, for example, since the AGV8 has not yet reached the set last waypoint (destination), the AGV8 continues to run until it reaches the last waypoint. At that time, the AGV8 continues running according to either the motion plan or the motion plan according to the presence / absence of the event presence / absence condition (S304) and the presence / absence of the correction command (S306).

On the other hand, when the operation completion condition is satisfied, the traveling control unit 8122 stops the AGV8 (S310). In this case, assuming that the AGV 8 has reached the destination, for example, the travel control unit 8122 stops the AGV 8 without continuing the travel. This completes the running process for the stopped AGV8. At that time, the travel control unit 8122 transmits a signal indicating that a series of controls (travel processing) in the operation plan of the AGV8 has been normally completed to the AGV management unit 71 via the communication unit 86 and the communication management unit 73. Then, the management device 7 continues to perform the traveling process (S301 to S310) for each AGV8 until the traveling processing of all the AGV8s is completed. Then, the management device 7 ends the traveling process when, for example, all the AGV8s reach the destination and stop.

As described above, according to the control device 81 of the present embodiment, in addition to the same effects as those of the first embodiment described above, the following effects are exhibited.
In the correction of the operation plan, the correction command unit 72 of the management device 7 resets the passing time of the waypoint, so that the processing load of the control device 81 can be reduced. Therefore, for example, the performance of the CPU, the memory, the storage device (nonvolatile memory), and the like can be suppressed, and the cost can be reduced. Further, in modifying the motion plan, the arithmetic processing for resetting the speed and acceleration of the AGV 8 is executed not by the management device 7 but by the control device 81. Therefore, the amount of data communication between the AGV 8 and the management device 7 via the communication network NW can be suppressed. Therefore, the time lag during communication can be suppressed, and the response from the occurrence of the event to the correction of the operation plan can be improved. Therefore, the AGV8 can be quickly changed to an appropriate driving mode when an event occurs. If the waypoint data does not include acceleration, the arithmetic processing for resetting the acceleration becomes unnecessary, and the arithmetic processing at the time of motion planning correction in the control device 81 can be speeded up. Further, when modifying the operation plan, it is not necessary to reset all the waypoint data of all the AGV8 operation plans in the management device 7. Therefore, the processing load in the management device 7 can also be reduced.

Although some embodiments of the present invention have been described above, the above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Cargo handling device, 2 ... Control device, 3 ... Article movement mechanism (cargo handling robot), 4 ... Detection unit, 5 ... Notification unit, 11 ... Integration area, 12 ... Movement destination area, 21 ... Motion planning means, 22 ... Operation Planning correction means, 23 ... control means, 31 ... gripping unit, 32 ... arm unit, 33 ... gripping state detection unit, 41 ... first detection unit, 42 ... second detection unit, 211 ... orbit setting unit, 212 ... Interference check unit, 213 ... Passing time setting unit, 214 ... Operation plan formulation unit, 221 ... Passing time correction unit, 222 ... Correction operation plan formulation unit, 231 ... Arm control unit, 232 ... Grip control unit, 233 ... Event determination unit , 100 ... Automatic driving system, 7 ... Management device, 71 ... AGV management unit (motion planning means), 72 ... Correction command unit, 73 ... Communication management unit, 8 ... Article movement mechanism (AGV), 81 ... Control device, 82 ... Accommodation unit, 83 ... Drive unit, 84 ... Detection unit, 85 ... Storage unit, 86 ... Communication unit, 811 ... Correction operation plan formulation unit (motion plan correction means), 812 ... Control means, 8121 ... Position estimation unit, 8122 ... Travel control unit, 8123 ... Event judgment unit, TB1, TB2 ... Waypoint data table.

Claims (9)

A control device that controls the operation of an article moving mechanism that moves an article.
An operation plan formulated by setting a plurality of waypoints including a start point and an end point of a flow line of the article movement mechanism at the time of movement of the article and a passing time when the article movement mechanism passes through each waypoint. Among the set values, an operation plan correction means for formulating a correction operation plan in which the operation plan is modified by delaying or advancing the passage time without changing the waypoint, and
A control means for operating the article moving mechanism from the start point to the end point based on the presence or absence of a factor that hinders the operation of the article moving mechanism in the flow line is provided.
When the factor is not present, the control means controls the operation of the article moving mechanism according to the motion plan, and when the factor is present, the control means causes the motion plan correction means to formulate the correction motion plan, and the motion plan is corrected. A control device that controls the operation of the article moving mechanism according to a plan. A claim that the motion plan modifying means adds a transit point of the article moving mechanism when the factor occurs, and modifies the motion plan by delaying or accelerating the transit time after the transit time of the added transit point. The control device according to 1. The article moving mechanism is connected to a grip portion that releasably grips the article by at least one joint portion, and rotates each joint portion around a predetermined axis from the start point to the end point together with the grip portion. It is a cargo handling robot of the article provided with an arm portion that operates in the same manner.
The motion plan is formulated by setting the angular velocity of each joint portion of the arm portion at the transit point so that a predetermined reference point of the arm portion passes through the transit point at the passing time.
The motion plan modifying means according to claim 2 for formulating the modified motion plan by resetting the angular velocity so that the reference point of the arm portion passes through the transit point later or earlier than the passing time. The control device described. The control device according to claim 3, wherein the motion planning modifying means functions the angular velocity of each joint portion of the arm portion at each transit point after the added transit point with time, and resets the angular velocity. The control device according to claim 3, wherein the motion plan correcting means sets the flow line in the joint coordinate system of the arm portion based on the inverse kinematics. The control device according to claim 3, wherein the control means determines the presence or absence of the factor based on a determination condition including at least one of the presence of an infringing object in the flow line and the gripping state of the article. The article moving mechanism is a transport vehicle for the article including a storage section for accommodating the article and a drive unit that operates together with the accommodation section from the start point to the end point.
The motion plan is formulated by setting the speed of the transport vehicle at the transit point so that the transport vehicle passes through the transit point at the passing time.
The control device according to claim 2, wherein the motion plan modifying means resets the speed so that the carrier passes the transit point later or earlier than the passing time, and formulates the modified motion plan. .. The control device according to claim 7, wherein the motion planning correction means functions the speed of the transport vehicle at each waypoint after the added waypoint with time and resets the speed. The transport vehicle is centrally managed by a management device together with a plurality of other transport vehicles.
The control device according to claim 7, wherein the motion planning correction means resets the speed based on the passage time corrected by the management device by delaying or advancing the passage time after the added waypoint. ..

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