WO2019029870A1

WO2019029870A1 - Handling device having a robot, and method and computer program

Info

Publication number: WO2019029870A1
Application number: PCT/EP2018/065689
Authority: WO
Inventors: Felix Beuke; Simon Jessen; Sergey Alatartsev
Original assignee: Robert Bosch Gmbh
Priority date: 2017-08-07
Filing date: 2018-06-13
Publication date: 2019-02-14
Also published as: DE102017213651A1; JP2020529931A; KR102553391B1; JP7003220B2; KR20200038468A; CN110914020A; CN110914020B

Abstract

Robots having a plurality of arms are increasingly used in industrial production. The invention relates to a handling device (1), comprising: a robot (2), wherein the robot (2) has a plurality of kinematic chains (4a, 4b), wherein each of the kinematic chains (4a, 4b) can be moved in a working space, at least two of the working spaces have an overlap, each kinematic chain (4a, 4b) is designed to perform a working movement; a control module for controlling the kinematic chains (4a, 4b) in order to perform a total movement, wherein the total movement can be provided by means of the working movements of the kinematic chains (4a, 4b), and the control module is designed to control the kinematic chain on the basis of a trajectory function (q1, q2) for performing the working movement; and a trajectory determination module and a reparameterization module, wherein the trajectory determination module is designed to determine, for each of the working movements of the kinematic chains (4a, 4b), a minimum time trajectory (q1),(t1)q2(t2)) as the trajectory function (q1, q2), and the reparameterization module is designed to reparameterize the trajectory function (q1, q2), which is based on the minimum time trajectory (q1),(t1)q2(t2)), such that the total movement is free of collisions.

Description

Description title

Handling device with a robot and method and

computer program

State of the art

A handling device with a robot is proposed, wherein the robot has a plurality of kinematic chains, wherein each of the kinematic chains is movable in a working space, wherein at least two of the working spaces have an overlap, wherein each of the kinematic chains is designed to carry out a working movement , with a control module for controlling the kinematic chains by one

Perform overall movement, the total movement is represented by the working movements of the kinematic chains. Furthermore, a method for driving a robot and a computer program is proposed.

The use of robots in the automation of processes and in particular in industrial manufacturing is known from the prior art.

The document DE 10 2013 014 287 A1, which is probably the closest prior art, describes a method for joining fine mechanical components by laser welding with the following steps: grasping a first component from a first magazine area with one at a first

Robotic arm provided first gripper. Gripping a second component from a second magazine region with a second gripper provided on a second robot arm for holding the first component with the first Gripper and holding the second component with the second gripper relative to each other and relative to a laser device in a first mounting position. Activation of the laser device and connect the first and the second component to each other by means of a first welded joint in the first mounting position to an assembly. Laying the assembly by means of the first gripper in a storage area.

DISCLOSURE OF THE INVENTION A handling device with a robot with the features of the

Proposed claim 1. Furthermore, a method for driving a robot, in particular a robot of a handling device, with the features of claim 11 and a computer program with the features of claim 12 is proposed. Further advantages and effects will become apparent from the dependent claims of the following description.

It is proposed a handling device with a robot.

In particular, the handling device is a device of an industrial automation technology. The handling device is, for example, a robot workstation, a production station and / or a mounting station. The robot is preferably designed to carry out an assembly step and / or a production step. In particular, the robot is a single-arm robot, a two-arm robot or a multi-arm robot. Furthermore, the robot may be an articulated robot. In particular, the robot is designed as a multi-axis robot. In particular, the handling device can be a plurality of

Have robots.

The robot has a plurality of kinematic chains. In particular, the robot has exactly two or more than two kinematic chains. In particular, the robot may have more than five and / or more than ten kinematic ones

Have chains. Preferably, the robot has an end effector at the end of the kinematic chain. Each of the kinematic chains is in one

Working space movable. In particular, the end effector is movable in the working space. The working space is in particular a three-dimensional space.

Preferably, each point of the working space is through the kinematic chain and / or reachable by the end effector. At least two of the workspaces have an overlap. The overlap can be one and / or both

Completely enclosing work spaces.

The kinematic chains are designed to carry out a working movement. The working movement serves, for example, to carry out the production and / or assembly step. The working movement can

For example, be a start of a point and / or a coordinate with the end effector.

The handling device and / or the robot has a control module for controlling the kinematic chains. In particular, the control module is designed to control kinematic chains independently. The activation of the kinematic chain is in particular for carrying out a working movement. An overall movement can be represented by the working movements of the kinematic chains. In particular, the total movement is the result of a series execution and / or combination of the working movements of the kinematic chains. The total movement may be a synchronous movement of the kinematic chains, for example a two-armed lifting or a device-free mounting. Alternatively, the overall motion is an asynchronous motion of the kinematic chains, such as gripping different workpieces with different kinematic chains one after another. The control module is formed, the kinematic chain based on a

To control the trajectory function for carrying out the work movement. The Trajekto rienfunktion is in particular a vector-valued function. For example, a kinematic chain comprises a number n of movable joints, the associated trajectory function being a vector with n entries, each entry indicating an angular position of the associated joint. Furthermore, the

Trajektorienfunktion in addition to angular positions also include Verstellgeschwindigkeiten and Verstellbeschleunigungen a joint. The control module is preferably designed to serve in a discretized form as setpoint generator for the kinematic chain and / or joints. The handling device comprises a trajectory determination module and a reparamization module. In particular, that can

Trajektorienbestimmungsmodul and the reparametrization module be part of the control module. The control module, the trajectory determination module and / or the reparamization module are for example one

Computer unit, a processor or a microchip.

The trajectory determination module is configured for each of

Working movements of the robot and / or each working movement of the kinematic chains in each case to determine a minimum time trajectory as a trajectory function. In particular, the trajectory determination module is designed to determine a minimum time trajectory for each of the kinematic chains of the robot independently of the other kinematic chains of the robot.

The repair parameterization module is implemented on the

To reparametrize minimal-time trajectory-based trajectory functions. In particular, the reparametrisierte trajectory function is designed so that kinematic chains perform the working movements so that the

Total movement is collision-free. Preferably, the control module is designed to control the kinematic chains based on the reparametrisierten trajectory functions.

The invention is based on the consideration of an automated

To provide handling device with a robot that can perform its tasks collision-free. Advantages over the prior art, for example, that the use of symbolic planning at a higher level of abstraction is possible. Furthermore, an error-prone and time-consuming manual coordination of the kinematic chains can be omitted. By using the control module, the planned movements and / or processes of the robot are guaranteed to be collision-free. In particular, an advantage is that inherently asynchronous motions do not have to be artificially synchronized in advance.

In one possible embodiment of the invention, it is provided that a kinematic chain, a plurality of kinematic chains and / or all kinematic chains are each designed as a robot arm and / or manipulator. The robot arms are designed to perform a mechanical work. For example, by means of the robot arm a

manipulating task, for example, welding, cutting or another manufacturing process can be performed. In particular, the robot arm is designed to carry out a positioning task and / or a measuring task. For example, the robot arm includes a gripper as end effector.

Preferably, the robot arm comprises a plurality of axes of rotation and / or shear axes for performing the working movement.

It is particularly preferred that the minimum time trajectory the

Trajectory function is that which takes a minimum time to perform the work movement. In particular, the minimal time trajectory is the

Trajectory function that is reparametrisiert with a function for a given path, taking into account kinodynamic constraints of the robot and / or the kinematic chain so that overall results in a minimum execution time for the working movement.

Optionally, it is provided that the trajectory determination module is designed, the minimum time trajectory based on a finite

Maximum acceleration and / or a finite maximum speed of the kinematic chain and / or one of the joints to determine. In particular, a finite adjustment speed and / or finite adjustment acceleration of the kinematic chain and / or a joint is understood as a kinodynamic restriction.

In one possible embodiment of the invention, it is provided that the repair parameterization module is designed to repair the overall movement with a global time curve. It is provided in particular that for a robot with a number of x kinematic chains the

Global time curve is a curve in x-dimensional space, especially in R ^x . Specifically, the global time curve is writable by means of point tuples, with each entry in that point tuple describing a point in time on the

Minimal time trajectory corresponds to a kinematic chain. The dot tuple In particular, time points and / or positions on different minimum-time trajectories are assigned to one another.

In a particularly preferred embodiment of the invention, it is provided that the minimum time trajectories are each described by means of a proper time by the trajectory determination module. In particular, the proper time extends from an initial time to an end time, and the

Own time determines where the kinematic chain is located on the minimum time trajectory between the start time and the end time.

The repair parameterization module includes a test function. The test function has as function arguments the minimum time trajectories. The test function has, based on the function arguments as output, in particular a "collision of the kinematic chains" or a "collision freedom of the

For example, if the kinematic chains collide as a function value, the test function outputs a value a, where a

1, for example, the check function outputs a value b as a function value in the event of any collision of the kinematic chains, where b is 0, for example. The reparamization module is configured to include a subspace in one

Split up collision space and an effective space. The subspace is

spanned by the proper time of the kinematic chains. For example, the robot has a number x of kinematic chains, the subspace being an x-dimensional subspace. In this case, the repair parameterization module is in particular designed to associate a point in the subspace with the collision space if a collision of kinematic chains has been detected and / or the test function outputs the value a.

Furthermore, the reparametrization module is in particular designed to assign a point in the subspace to the effective space if no collision of the kinematic chains has been detected and / or the test function outputs the value b. The repair parameterization module is preferably designed as a global time curve to determine a curve in the effective space. In particular, the global time curve has no point in the collision space. Optionally, it is provided that the total movement begins at a starting point and ends at an end point. The starting point is preferably a point in the working space, wherein a time coordinate can be assigned to the starting point in the subspace. The time coordinate of the starting point in the subspace corresponds in particular to the zero points of the minimum time trajectories of the kinematic chains in the subspace. The end point is preferably a point in the working space, wherein a time coordinate can be assigned to the end point in the subspace. The time coordinate of the end point in the subspace corresponds in particular to the end points of the minimum time trajectories of the kinematic chains in the subspace. The reparametrization module is designed to determine, as the global time curve, a shortest connection between the time coordinate of the starting point and the time coordinate of the end point.

Alternatively and / or additionally, it is provided that by

Reparametrisierungsmodul as global time curve a fastest connection between the time coordinate of the starting point and the time coordinate of the end point is determined.

It is particularly preferred that the control module is designed to

Control of the robot to convert the reparametrisierte minimal time trajectory using an inverse kinematics. In particular, the robot or the controller of the robot is based entirely on an inverse kinematics.

A particularly preferred embodiment of the invention provides that the total movement comprises an asynchronous working movement of at least two kinematic chains. For example, the asynchronous

Work movement the sequential gripping a workpiece with two different robot arms and / or kinematic chains.

Another object of the invention is a method for driving a robot. In particular, the method for controlling the robot with the handling device is designed according to one of the preceding claims. The method provides that a minimum time trajectory is determined for each kinematic chain of the robot. The minimum-time trajectory is in particular for describing a working movement of the kinematic chain educated. According to the method, the trajectory function based on the minimum-time trajectory is reparametrized such that an overall movement of the kinematic chains is collision-free.

Another object of the invention is a computer program with program code means for carrying out the method described above, when the computer program on a computer or the

Handling device is executed.

Further features, advantages and effects of the invention will become apparent from the following description of preferred embodiments of the invention and the accompanying figures. Showing:

Figure 1 shows a handling device as a first embodiment;

Figure 2 shows an embodiment of a subspace;

FIG. 3 shows the subspace with collision space and effective space;

FIG. 4 shows the subspace with global time curve;

Figure 5 shows the subspace with global time curve and indicated

Trajektorienfunktionen.

Figure 1 shows a handling device 1 with a robot 2 as an embodiment of the invention. The handling device 1 is a mounting station of a production plant. The robot 2 is designed for processing and / or mounting an object 3, for example a workpiece. In this case, the robot 2, the object 3 grab, transport and edit.

The robot 2 has a first kinematic chain 4a and a second kinematic chain 4b. The first and second kinematic chains 4a, 4b are each designed as a robot arm. The first kinematic chain 4a has a plurality of joints 5a and the second kinematic chain 4b has a plurality of joints 5b. The joints 5a and 5b are changeable in their angular position, so that by means of the joints 5a and 5b the

kinematic chains are each movable in a working space. In particular, the joints 5a and 5b with an adjustment speed and a

Verstellbeschleunigung controlled to move, the joints 5a and

5b have a maximum speed and a maximum acceleration. At the free end of the kinematic chains 4a and 4b, respectively, an end effector 6a, 6b is arranged, wherein the end effectors 6a and 6b are each formed as a gripper for gripping the workpiece 3.

The kinematic chains 4a and 4b are movable in the working space. The

End effector 6a is movable by means of the kinematic chain 4a from a starting point along a movement path si (t) to an end point. The end effector 6b is movable from a starting point along a moving path S2 (t) to an end point by means of the kinematic chain 4b.

The handling device 1 comprises a control module for controlling the kinematic chains 4a and 4b to run the path si (t) and S2 (t) with the end effector 6a and 6b. In this case, the kinematic chain 4a is actuated based on a trajectory function qi, the kinematic chain 4b being driven based on a trajectory function q2. The trajectory functions qi and q2 are each vector-valued functions, each having as many entries as the kinematic chain 4a, 4b has joints 6a, 6b. For example, the first kinematic chain 4a has three joints, with the associated kinematic chain 4a

Trajectory function qi, for example, by qi (0i, 0 ₂ , 0 ₃ ) is writable, where

0i.0 ₂ .0 ₃ each is an angular position of a joint. Furthermore, it is possible that the trajectory function the Verstellgeschwindigkeit and the

The adjustment acceleration of the joints comprises, for example, and is writable as {{{φ ^ φ ^ 0i), (0 ₂ , 02 02). (03-03-0s)) -

The handling device 1 comprises a trajectory determination module for determining in each case a minimum time trajectory qi and q2 for the kinematic chains 4a and 4b. The minimum-time trajectory is in each case the trajectory function for generating a movement of the kinematic chains 4a and 4b which requires the shortest time to execute the movement. To carry out the Minimal time trajectory qi requires the kinematic chain 4a the time Ti. To carry out the minimum time trajectory q2, the kinematic chain 4a needs the time T ₂ . The parameter that parameterizes the minimum time trajectories is a respective proper time τ ₁ , τ ₂ , where the minimum time trajectory qi then results, for example, in oiiicpi fi), φ ₂ (τ ₁ ), φ ₃ (τ ₁ )) = ί (τ ₁ ), and the minimum time trajectory is q ₂ (r ₂ ).

The handling device 1 comprises a reparametrization module, the reparametrization module reparametrieisert the minimum time trajectories qi and q ₂ by means of a global time curve † R SO that the total movement of the kinematic chains 4a and 4b is collision-free. The control module is in particular designed to control the kinematic chains 4a and 4b for carrying out the working movements and / or to control them by means of the reparametrized minimum-time trajectories. The control module uses the reparametrisierten minimal time trajectories as trajectory functions. The following figures show how the repair parameterization module

Minimal-time trajectory can reparametrisieren that the total movement is collision-free.

FIG. 2 shows a subspace 7, spanned by the proper times τ and τ ₂ . The subspace of this figure is an example of the subspace of

Handling device 1 from FIG. 1. The proper times τ and τ ₂ form, in particular, an orthonormal basis of the subspace 7. The proper time τ of the kinematic chain 4a forms the abscissa, whereby the proper time τ _{2 of} the kinematic chain 4b forms the ordinate. Below the abscissa, the time course of the minimum time trajectory qi ^ is shown graphically. To the left of the ordinate the temporal course of the minimum time trajectory q ₂ (r ₂ ) is shown graphically. Likewise, in the subspace the time coordinate T _s and τ _Ε indicated, the time coordinate T _s corresponds to the proper times, in which the

Total motion begins and the time coordinate τ _Ε corresponds to the Eigenzeiten, at which the total movement ends.

FIG. 3 shows a representation in which the subspace 7 from FIG. 2 was divided by the reparameterizing module into an effective space 8 and a collision space 9. For this purpose, the repair parameterization module comprises a test function c. The test function c has as arguments the minimum time trajectories qi ^) and q2 (r ₂ ), so that

q2 (r ₂ )). The test function c is designed to check whether or not the kinematic chains 4a and 4b collide for given minimum-time trajectories qi ^) and q2 (r ₂ ). In the event that the test function determines that there is no collision for given minimum-time trajectories qi ^) and q2 (r ₂ ) at a certain point in time (τ ^ τ ₂ ), the corresponding point (τ ^ τ ₂ ) in the subspace 7 becomes the effective space 8 counted. In the event that the test function determines that there is a collision for a given minimum time trajectory qi ^) and q2 (r ₂ ) at a certain point in time (τ ^ τ ₂ ), the corresponding point (τ ^ τ ₂ ) in the subspace 7 is added the collision space 9 counted. The repair parameterization module is designed to perform this check for collision and / or collision freedom for all times (TL, τ ₂ ).

Figure 4 shows the subspace 7 of Figure 3 with the of

Repair Parameter Module Specific Global Time Curve † R. The global time curve † R connects the time coordinate of the starting point with the time coordinate of the

End point. The global time curve † R represents the shortest connection between these two points, but with the condition that the global time curve † R runs exclusively in the effective space 8 and does not pass through the collision space 9. The global time curve † R can be represented as a parameterized curve in the form t _R = (T _LJ B, τ _{2, Λ} ).

FIG. 5 shows how the control module actuates the kinematic chains 4a, 4b based on the global time curve † R ZU for a collision-free overall task. In this case, the kinematic chains 4a and 4a according to the

Minimalzeittrajektorien

τ ₂ can only be controlled in combinations for which {τ ₁ τ ₂ ) = † R = (T _1R , T _2IR ).

Claims

claims

1. Handling device (1) with a robot (2), wherein the robot (2) comprises a plurality of kinematic chains (4a, 4b), wherein each of the kinematic chains (4a, 4b) is movable in a working space, wherein at least two the work spaces have an overlap, wherein each kinematic chain (4a, 4b) is designed to carry out a working movement, with a control module for controlling the kinematic chains (4a, 4b) to perform an overall movement, wherein the total movement by the working movements of the kinematic chains ( 4a, 4b), wherein the control module is designed to control the kinematic chains based on a trajectory function (qi, q2) for carrying out the working movement, characterized by a trajectory determination module and a

Reparameterization module, wherein the trajectory determination module is formed, for each of

Working movements of the kinematic chains (4a, 4b) one each

Minimum time trajectory (qi ^), q2 (r ₂ )) as trajectory function (qi, q2) to determine, wherein the Reparametrisierungsmodul formed on the

Minimal-time trajectory (qi ^), q2 (r ₂ )) based trajectory function (qi, q2) to reparametrisieren so that the overall movement is collision-free.

2. Handling device (1) according to claim 1, characterized in that the kinematic chain (4a, 4b) are each a robot arm.

3. Handling device (1) according to claim 1 or 2, characterized

characterized in that the minimum time trajectory (qi ^), q2 (r ₂ )) the

Trajectory function (qi, q2), which takes a minimum time to perform the working movement.

4. Handling device (1) according to one of the preceding claims, characterized in that the Trajektorienbestimmungsmodul is formed, the minimum time trajectory (qi ^), q2 (r ₂ )) based on a finite

Maximum acceleration and / or a finite maximum speed to determine.

5. Handling device (1) according to one of the preceding claims, characterized in that the repair parameterization module is designed to repair the total movement with a global time curve tR.

6. Handling device (1) according to one of the preceding claims, characterized in that the robot (2) has a number n of kinematic chains (4a, 4b), wherein the global time curve tR is a curve in an n-dimensional space.

7. Handling device (1) according to one of the preceding claims, characterized in that by the Trajektorienbestimmungsmodul the

Minimal time trajectories (qi ^), q2 (r ₂ )) are each described by means of a proper time τ ₁ , τ ₂ ), wherein the reparametrization module is a test function

(cfaiCr _! ), q2 (r ₂ )) for checking a collision of the kinematic chains, and the reparametrization module is designed, a subspace (7), spanned by the proper times (τ ₁ , τ ₂ ), in a collision space (9) and dividing an effective space (8), wherein the collision space (9) is defined by the points in the subspace (7) for which the check function c detects a collision of the kinetic chains (4a, 4b), and the effective space (8) through the Points in the subspace (7) is defined, for which the test function a collision freedom of the kinematic Chains (4a, 4b) determines, the reparametrization module is designed as a global time curve † R to determine a curve in the effective space (8).

8. Handling device (7) according to claim 7, characterized in that the total movement begins at a starting point and ends at an end point, wherein the starting point in the subspace (7) a time coordinate (r _s ) can be assigned and the endpoint a time coordinate (τ _Ε ), wherein the repair parameterization module is designed to determine the global time curve † R as the shortest connection between the time coordinates of the end point and the starting point in the effective space (7).

9. Handling device (1) according to one of claims 6 to 8, characterized in that the total movement begins at a starting point and ends at an end point, wherein the starting point in the subspace (7) a

Time coordinate (T _s ) can be assigned and the end point, a time coordinate (r _B ) is assigned, the reparametrization module is configured to determine the global time curve † R as the fastest connection between the time coordinates of the starting point and the end point in the effective space (7).

10. Handling device (1) according to one of the preceding claims, characterized in that the control module is designed to control the robot (2) to convert the reparametrisierte minimal time trajectory (qi ^), q2 (r ₂ )) by means of an inverse kinematics.

11. Handling device (1) according to one of the preceding claims, characterized in that the total movement comprises an asynchronous working movement of two kinematic chains (4a, 4b).

12. A method for controlling a robot (2), in particular with the handling device from one of the preceding claims, characterized in that for each kinematic chain (4a, 4b) of the robot (2) a minimum time trajectory (qi, q2) is determined, the on the

Minimal time trajectory (qi ^), q2 (r ₂ )) based trajectory function (qi, q2) so reparametrisiert that a total movement of the kinematic chains (4a, 4b) is collision-free.

13. Computer program with program code means for carrying out characterized in that the method of claim 11 is performed when the computer program on a computer or the handling device

(1) is executed.