TW202003175A - Method for inserting objects into a common object receptacle - Google Patents

Abstract

The present invention concerns a method for inserting objects (5) into a common object holder (4) by means of a robot manipulator (1) and a robot manipulator (1) for carrying out such a method.

Description

Method for inserting object into common object receptacle

The invention relates to a method for inserting at least two objects into a common object holder using a robot manipulator. In addition, the present invention relates to a robot manipulator for performing this method.

Various products are combined and packaged in larger units for delivery. For example, the smaller packaging unit is housed in a larger packaging unit such as a cardboard box.

Depending on the weight, size and nature of the product or unit to be packaged, this packaging may still be performed almost entirely manually.

These manual procedures have the disadvantage that the filling speed associated with packaging is usually limited and depends on the skills of the packaging personnel.

In addition, there are automated procedures, such as the use of pick & place robots. However, these automated procedures require an extremely high and therefore economically undesirable amount of programmed workload, which only applies to precisely defined locations in space.

Against this background, an object of the present invention is to provide a simple, robust and more cost-effective method for inserting several objects into an object holder common to these objects by means of a robotic manipulator. In addition, a target provides a robot manipulator trained to perform this method.

This goal is achieved by the method of using a robotic manipulator to insert objects into a common object receptacle as in technical solution 1 and the robotic manipulator as in technical solution 10.

In a first aspect, therefore, the present invention relates to a method of inserting objects into a common object receptacle and controlling the robot manipulator by means of a robot manipulator driven by a robot's actuator, the robot manipulator At its distal end there is an actuator (effector) which is designed to receive and/or grab objects, The method steps are as follows: a) Picking up a first object from a storage device by the actuator; b) transferring the first object to the object receptacle by virtue of the robot manipulator allows the first object to be inserted into the object receptacle by virtue of the robot manipulator; c) Use the robot manipulator to insert the first object into the object receptacle along a first insertion trajectory; d) The first object is released by the actuator; e) Picking up a second object from a storage device by the actuator; f) transferring the second object to the object receptacle by means of the robot manipulator allows the second object to be inserted into the object receptacle by means of the robot manipulator; g) use the robot manipulator to insert the second object into the object receptacle along a second insertion trajectory; and h) release the second object by the actuator; The second insertion trajectory during the insertion is determined by the following: -The second object is in contact with one of the first objects already present in the object receptacle; and/or -The second object is in contact with one of the inner boundaries of an object receptacle; and/or -The first object moves relative to one of the second objects in the object receptacle.

A packaging or cardboard box for containing smaller items is preferably designed in such a way that it can hold n items, and the items are also sized in such a way that when the package is fully filled, the items The storage space of the package is substantially completely filled. In another embodiment of the invention, therefore, the method is designed in such a way that the above steps e) to h) are repeated (n-2) times for each further object until the object receptacle is completely Until loading, the insertion trajectory of each further object is determined by the following: -Contact of the further object with at least one of the objects already in the object receptacle; and/or -The further object is in contact with one of the inner boundaries of the object receptacle; and/or -The objects already present in the object receptacle are displaced with respect to each other and/or with respect to one of the other objects in the object receptacle.

In an advantageous variant of the method, for each object, the insertion trajectory is defined or determined by identifying the progress status of the insertion of the individual objects and/or whether the insertion of the individual objects has been successfully completed, the State by reaching or exceeding at least one predetermined limit value condition of a torque acting on the actuator and/or a force acting on the actuator and/or reaching or exceeding the force provided by one of the actuators/ Defined by the torque indicator and/or a position/speed indicator.

The robot manipulator is preferably designed to individually follow these respective insertion trajectories of each object by force/rotation/tilt movement and/or translation movement controlled by the robot manipulator.

In another advantageous embodiment of the method, if an error occurs when inserting the objects into the object receptacle along the respective insertion trajectories by the robot manipulator, the robot manipulator can be used, Use one of the modified insertion trajectories of the corresponding object and/or use the modified parameters of the translation and/or rotation/tilt movement of the corresponding object's force control and/or impedance control to repeat the insertion of the object into the object volume In the seat.

In other words, the core of the present invention lies in the fact that the robot manipulator can basically "freely" (ie, in any order relative to the configuration of individual objects) fill the object receptacle, while being used by the robot during the further filling process The contact force detected by the detector is used as an orientation aid within the control frame. This contact force is generated when the object to be inserted and one or more inserted objects occur on the one hand and on the other hand between the object to be inserted Occurs when contact occurs between internal boundaries (such as side walls and bottom surfaces).

Since the size and position of the object receptacle already known by the robot and the size of the object to be inserted (this is stored in a memory of the control unit of the robot), a program that realizes one of the methods according to the present invention knows that the robot manipulator has transferred the object Where is it stored in the object receptacle, and therefore where is the free space that can still be used to insert other objects, and considering the predefined tolerances, then it can be aligned accordingly for further insertion or packaging strategies .

Both the inner boundary of the object receptacle and the outer boundary of the object (packaging) can advantageously be used as guiding surfaces for insertion by the robotic manipulator, and the robotic manipulator uses these guiding surfaces in the context of its compliant behavior, as follows Interpretation.

During the insertion of an object, both lateral translation and rotation/tilt movement take into account that the remaining free space can be used to move the object inserted into the object receptacle, and on the other hand, it can be used to offset the gap between the object and the object receptacle Tolerance tolerances ensure that objects can be inserted more easily. In addition, during the insertion procedure, these movements can be used to overcome the frictional resistance that occurs between the two surfaces when guided strictly linearly.

In order to automatically perform the individual method steps described above in the process of equipping a package with the items described, it is advantageous to perform these steps preferably by means of a robot designed to be compliant and/or sensitive.

Robots with position-controlled axes are generally not suitable for these steps in the method because the force acting on the robot from the outside must be measured for position control. These forces form the basis of the desired dynamic behavior, which are then transmitted to the robot via inverse kinematics (also called admittance control).

In this case, a strictly position-controlled robot cannot be programmed at all. This is because the "free" placement of the object is completely unable to use one of the "free" movement of the object in the object receptacle due to the lack of accurate coordinates in the space. Mapping.

Due to the control principle used, these position control robots will also be unable to detect errors or deviations (for example, when the actuator picks up the object to be inserted from a storage device for whatever reason, the to-be-inserted In case the actual position of the object deviates slightly from the set position provided for this purpose) in order to react accordingly. It is only possible to perfectly insert the object into the available space in the object holder only if the free available space is accurately provided relative to the working range of the robot (ie, relative to the object holder) within the stylized frame.

In order to perform this method, one of the cores of the present invention is that the robot used (at least one robot) has this integrated compliance control, or is equipped with an inherent compliance or a combination of active and passive compliance, also by lightweighting These programmable robotic manipulators of the designed robot preferably perform this method.

In this context, it should be mentioned that the compliance control is based on, for example, the so-called impedance control, which is based on the torque control at the joint level in contrast to the admittance control already mentioned. Depends on a desired dynamic behavior and considers the deviation of an actual position from a defined target position, and/or the deviation of an actual speed from a target speed, and/or the deviation of an actual acceleration from a target acceleration, to determine the force or The torque, the forces or torques are then mapped to the corresponding joint torque set via the torque control via the known kinematics of the robot (which is generated by the number and configuration of the joints and axes of the manipulator and thus the degrees of freedom). The torque sensor element integrated into the joints records the dominant one-dimensional torque at the output of the gear of the drive unit located in the joint, which can consider the elasticity of the joint in the control range as a measured variable In. In particular, as in admittance control, using only one torque sensor on the actuator, using a corresponding torque sensor device also allows measurement of the connection that is not applied to the actuator but applied to the robot The force exerted on the rod and on an object held by the robot or to be processed by the robot when an object is inserted into an object receptacle. These torques can also be measured through the structure of the robot system and/or force sensors in the base. In particular, joint mechanisms between individual axes of the manipulator that allow multi-axis torque detection can also be used. A translational joint equipped with a stress sensor can also be envisaged.

It proves that the compliance control and sensitivity achieved in this way are advantageous to the present invention in many aspects.

In principle, this compliance control allows the robot used for the intended method or the individual method steps of the intended method to be able to perform controlled internal movements, whereby these internal movements correspond to the individual steps of the method. In this context, this robot will also (if necessary) independently "search" and non-destructively "feel" the objects and storage devices as well as the different positions of the receptacles or freely available spaces within the receptacles of the objects .

For example, these internal movements occur together with guiding the object to be inserted along the surface of the inner boundary of the object receptacle and the surface of the outer boundary of the inserted object.

Another advantage of this compliance control is that it allows more inaccurate placement or inaccurate positioning of the object to be inserted, which means that both the storage device and the object receptacle can be manufactured with higher tolerances. Such an object receptacle may be easily deformed when in contact with cardboard packaging. The corresponding inaccuracies can be compensated in a corresponding manner by reducing the associated contact force when picking up and inserting these objects by means of a corresponding compliance adjustment.

The robotic manipulator is advantageously designed and arranged to move one of the determined points of the actuator (for example, the so-called "tool center point" (TCP)) or one of the determined points of the object along a predetermined insertion trajectory ( For example, its center of gravity or geometric center), whereby the center of gravity is determined individually by the individual objects.

Therefore, the insertion trajectory is advantageously determined depending on the relative starting position of the object disposed at the actuator relative to its intended storage space in the object receptacle, the geometric configuration of the object, and the geometry of the object receptacle structure.

When inserting an object, the insertion trajectory is preferably a straight line toward the intended storage space. However, three-dimensional, single or multiple inclined curves are also conceivable until the object can be inserted into the storage space.

The actuator can move at a relatively high speed along the respective insertion trajectories until it soon reaches the storage space. The actuator then moves towards the storage space at a much slower speed.

In principle, the robot manipulator must recognize the actual state of the inserted program. According to the invention, this is achieved by the aforementioned limit value conditions and/or individual labels. In principle, these signs are the specific characteristics of the force and/or torque and/or position and/or speed recorded on the robot manipulator that exceed a simple threshold. For example, such characteristic properties may include a specific time behavior of the measured force, torque, position, and/or speed and characteristic properties that depend on these parameters.

The aforementioned measures can significantly increase the success rate of the insertion procedure. As mentioned, therefore, the object to be inserted does not have to be accurately positioned inside the storage device, and furthermore, the actuator does not have to pick up the object accurately. Compliance-controlled robotic manipulators can apply the above compensation measures during the insertion process.

Therefore, it proves that the method according to the present invention is more economical than using one of the known acquisition programs of the position control robot.

Another aspect of the invention relates to a computer system having a data processing device, wherein the data processing device is designed such that a method as described above is executed on the data processing device.

Another aspect of the invention relates to a digital storage medium having electronically readable control signals, whereby the control signals can interact with a programmable computer system, in this way, a method as described above is carried out.

In addition, the present invention relates to: a computer program product having a program code stored on a machine-readable medium, which is used to execute the method as explained above when the program code is executed on a data processing device; and A computer program that is used to execute this method when the program is executed on a data processing device.

Another aspect of the present invention relates to a robot having a robot manipulator driven by an actuator. The robot manipulator has an actuator at its distal end. The actuator is designed to house an object. The robot manipulator includes A control unit that is designed and configured so that it can perform a method as set forth above.

According to the invention, the robot is preferably a lightweight articulated arm robot having a robot manipulator of at least 6 degrees, preferably 7 degrees of freedom.

According to the present invention, robots will be used in combination with products having substantially the same weight and dimensions to fill a package, which simplifies teaching.

Fig. 1 shows a schematic structure of a robotic station for performing an example of a method according to the invention using an example of packaging smaller units in a single cardboard box.

The proposed method of inserting several objects into a common object receptacle is implemented by means of a robot manipulator 1 driven by a robot's actuator. The robot manipulator 1 has an actuator 2 at its distal end, which has Gripping fingers 3 designed to hold and/or grab objects.

An object receptacle 4 (ie, a cardboard box for holding or packaging smaller objects 5, such as boxes) and a storage device 6 for these objects 5 are arranged in a defined fixed position in front of the fixed robot. The storage device is not necessarily fixed; the object 5 can also be continuously fed to the robot station or removed from a chute.

As can be seen in the enlarged illustration of FIG. 2, if the object receptacle 4 is only partially equipped, a free space 7 for accommodating other objects is formed.

The robot manipulator 1 uses its actuator 2 to grab a first object 5.1 (Figure 3a), lift the first object 5.1 (Figure 3b) and transfer the first object 5.1 to be inserted into the free space 7 (Figure 4a) One in the starting position.

Following a first trajectory T, as shown in FIG. 4a, the robotic manipulator 1 then places the object 5.1 in the free space 7 (FIG. 4b) and then retracts (FIG. 4c), leaving both sides of the object 5.1 Under full space, as seen in Figure 5.

The robotic manipulator 1 then grabs a second object 5.2 (FIG. 6) and transfers the second object 5.2 to one of the starting positions for insertion into the object receptacle 4 (FIG. 7a).

7a to 7i show the insertion of the second object 5.2 in detail.

The robotic manipulator 1 lowers the object 5.2 (Figure 7a) and at the same time brings the object 5.2 to the right wall or inner boundary of the box 4 (Figure 7b) until the object 5.2 stays on an object 5 that already exists in the object receptacle 4 ( Figure 7c).

Then the robotic manipulator 1, using the wall of the box 4 on the one hand and the surface of the object 5 located thereon on the other hand, pushes the object 5.2 towards the object 5.1 (Figure 7c), whereby when in contact with the object 5.1, the robotic manipulator 1 Tilt the object 5.2 slightly (this is indicated by the corresponding arrow) (Figure 7d), so that the object 5.2 can be joined in free space in front of the object 5.1 to move the object 5.1 as part of a further translational movement to the front wall of the box 4, and Then finally move the object 5.2 down into the resulting free space by a translational movement (Figure 7e). Here, the robot manipulator 1 can perform a slight tilt movement.

Finally, the robot manipulator 1 inserts the object 5.2 (FIG. 7f, FIG. 7g), releases the object 5.2 and slides the object 5.2 downward by the final distance (FIG. 7h), after which the robot manipulator (FIG. 7i) is withdrawn to obtain another object 5.

Obviously, during the insertion procedure with respect to object 5.2, a three-dimensional trajectory consisting of several horizontal and vertical translations and tilting and/or rotational movements is traversed.

In this context, all movements of the robot manipulator 1 are controlled by force and/or impedance. The outer surface of the inserted object 5 and the inner wall of the package 4 serve as a guide surface for the robot manipulator 1 which, together with the guide surface, in the scope of its compliance control.

All the above-mentioned insertion and displacement movements have the following in common: the robot manipulator 1 is designed to use its control unit based on at least one predetermined ideal limit value condition G _i (for example, a reaction force generated by a fully inserted object 5) or based on An ideal force/torque indicator and/or position/speed indicator Si to identify the progress of the insertion process or whether each object 5 is fully inserted into the space provided for this purpose.

If the sensor of the robot (for example, by virtue of torque, and if necessary, the force sensor disposed in the joint of the robot manipulator 1) detects that it is not easy to insert each individual object 5 into its receptacle ( This is because during a better translational insertion movement along the respective insertion trajectory, the object 5 cannot be accurately inserted into the receptacle, which can also be defined by the corresponding predetermined limit value condition G _i and/or the label S _i ), then The robot manipulator 1 and its actuator 2 can perform force and/or impedance controlled rotation/tilt movement and/or lateral translation movement (not shown in the figure) until the object 5 is accurately engaged in the receptacle, and then the robot The manipulator 1 performs the final translation insertion movement.

Therefore, the robot manipulator 1 is designed in such a way that the robot manipulator 1 "feels" or "senses" the respective free space 7 or the boundary or edge of the respective free space 7 and the inserted object 5 during the insertion procedure .

All movements of the above method steps can be repeated until the box 4 is completely filled, so that the packaging of these items can be performed automatically and reliably. The assembly cycle time can be reduced, thereby making the automation process more economical.

The movement of the robot manipulator 1 in all the method steps explained above is controlled by force and/or impedance and can be controlled by a user, preferably by mapping individual program steps within the entire method according to the invention A predefined App control system to teach or program to the robot.

1‧‧‧Actuator-driven robot manipulator/robot manipulator 2‧‧‧Actuator 3‧‧‧ grabbing finger 4‧‧‧Object Holder/Box/Package/Common Object Holder/Common Object Holder 5‧‧‧Object/inserted object/completely inserted object/each object/corresponding object/individual object 5.1‧‧‧First Object/Object 5.2‧‧‧Second Object/Object 6‧‧‧Storage device 7‧‧‧ Free space / each free space T‧‧‧ First track

Other advantages and features of the present invention result from the description of the embodiments shown in the drawings, in which: FIG. 1 schematically shows a configuration of a robot station for performing a method according to the invention; Figure 2 is an enlarged illustration of one of the object receptacles; 3a to 3b show the picking and transfer of a first object according to a method of the present invention; 4a to 4c show the insertion of the first object into the object receptacle according to the method of the present invention; Figure 5 is another enlarged view of the object receptacle; 6 shows the picking up of a second object according to the method of the present invention; and 7a to 7i show the insertion of the second object into the object receptacle according to the method of the present invention.

1‧‧‧Actuator-driven robot manipulator/robot manipulator

2‧‧‧Actuator

3‧‧‧ grabbing finger

4‧‧‧Object Holder

5‧‧‧ Object

6‧‧‧Storage device

Claims (11)

A method for inserting an object (5) into a common object receptacle (4) and controlling the robot manipulator (1) by means of a robot manipulator (1) driven by a robot's actuator, the robot manipulator (1) ) Has an actuator (2) at its distal end, the actuator (2) is designed to receive and/or grab the objects (5), wherein the method steps are as follows: a) by the actuator ( 2) Pick up a first object (5.1) from a storage device (6); b) Transfer the first object (5.1) to the object receptacle (4) by means of the robot manipulator (1) The robot manipulator (1) inserts the first object (5.1) into a position in the object receptacle (4); c) along the first insertion trajectory (T _5.1 ) by virtue of the robot manipulator (1) Insert the first object (5.1) into the object receptacle (4); d) release the first object (5.1) by the actuator (2); e) from the one by the actuator (2) The storage device (6) picks up a second object (5.2); f) transfers the second object (5.2) to the object receptacle (4) by virtue of the robot manipulator (1) 1) Insert the second object (5.2) into a position in the object receptacle (4); g) Use the robot manipulator (1) along a second insertion trajectory (T _5.2 ) to insert the second object The object (5.2) is inserted into the object receptacle (4); and h) the second object (5.2) is released by the actuator (2); wherein the second insertion trajectory (T _5.2 ) is borrowed during insertion Judging by: the second object (5.2) is in contact with one of the first objects (5.1) already in the object receptacle (4); and/or the second object (5.2) and the object One of the inner boundaries of the receptacle (4) contacts; and/or the displacement of the first object (5.1) relative to a second object (5.2) in the object receptacle (4). The method of claim 1, wherein the object receptacle (4) is designed to receive n objects (5), and steps e) to h) are repeated for each further object (5) (n-2) times Until the object receptacle (4) is completely filled, and the insertion trajectory (T _n ) of each further object (5) is determined by the following: the further object (5) and the object receptacle ( 4) one of the objects (5) already present in contact; and/or the further object (5) is in contact with one of the inner boundaries of the object receptacle (4); and/or the The objects (5) already present in the object receptacle (4) are displaceable relative to each other and/or to another object (5) within the object receptacle (4). As in the method of claim 1 or 2, wherein the insertion trajectory (T _n ) of each object (5) is by identifying the progress status of the insertion of the individual objects (5) and/or identifying the individual objects ( 5) Whether the insertion has been successfully completed is judged, and the state is thus defined as: reaching or exceeding a torque acting on the actuator (2) and/or a force acting on the actuator (2) At least one predetermined limit value condition (G _i ), and/or a force/torque indicator (S _i ) and/or a position/speed indicator (S _i ) provided or exceeded by one of the actuators (2). A method as claimed in claim 1 or 2, wherein each object is followed by the robot manipulator (1) by means of the robot manipulator (1) force control and/or impedance controlled rotation/tilt movement and/or translation movement (5) The insertion locus (T _n ). The method of claim 4, wherein if an error occurs when inserting the object (5) into the object receptacle (4) along the respective insertion trajectory (T _n ) by the robot manipulator (1) , By virtue of the robot manipulator (1), using one of the corresponding objects (5) with a modified insertion trajectory (T _n *) and/or using the corresponding object (5) to control the translation of the force and/or impedance And/or the modified parameters of the rotation/tilt movement, repeating the insertion of the object (5) into the object receptacle (4). A computer system having a data processing device configured to execute the method according to any one of the foregoing request items 1 to 5 on the data processing device. A digital storage medium having electronically readable control signals that interact with a programmable computer system so that the method according to any one of the aforementioned request items 1 to 5 is executed. A computer program product having a program code stored on a machine-readable medium, the computer program product is used to execute any one of the foregoing request items 1 to 5 when the program code is executed on a data processing device method. A computer program with a program code, which is used to execute the method according to any one of the foregoing request items 1 to 5 when the program is running on a data processing device. A robot including a robot manipulator (1) driven by an actuator, the robot manipulator (1) having an actuator (2) suitable for accommodating an object (5) at its distal end, the robot manipulator (1) 1) Include a control unit adapted to perform one of the methods of any of the foregoing request items 1 to 5. A use as the robot of claim 10 for filling a package (4) with individual items (5) having substantially the same weight and size.

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