Method for calculating the quality of a robot relief device of a robot system

Abstract

In a robot system comprising a space robot device with at least one movable robot element and at least one actuator for moving the at least one robot element, a support device for supporting the robot device when the space robot device is used on Earth, and a force application element that is connected to the robot element at least at one point and applies at least one force to the robot element that at least partially compensates for the force of gravity acting on the robot element, it is provided that the support device is a cable robot system that has at least two cable elements that are connected to the force application element, wherein each cable element is connected to at least one motor that can move the respective cable element, such that the direction and amount of force that can be applied to the robot element via the force application element can be adjusted.

Description

[0001] The invention relates to a method for calculating the quality of a robot relief device of a robot system according to claim 1 and a robot system for calculating the quality of a robot relief device according to claim 9.

[0002] Robotic devices are known that are manufactured specifically for use in space. Space robotic devices are designed for conditions in space. Since no gravitational forces act on the space robotic device in space, a large portion of the forces required due to gravity can be neglected in the design of the space robotic device. This allows the joints and / or actuators to be smaller, lighter, and more energy-efficient.

[0003] However, the robot equipment will also be operated on Earth, for example to test or improve it. To do this, the robot equipment needs support, as otherwise the joints would be subjected to excessive strain or the actuators would be unable to move the robot equipment. For this purpose, load-bearing devices exist to support the robot equipment on Earth. This can be achieved, for example, with helium balloons or planar, active or passive support tables. Helium balloons, which can have a diameter of several meters depending on the payload, contribute to load relief through their buoyancy. These are mounted on the robot equipment at the designated points and pull the robot equipment upwards at this point with a constant force. Planar, movable support tables can, for example, glide over smooth floors and support the joints of the robot equipment.However, with this method, the robotic devices can only perform planar movements.

[0004] Robot systems are known, each comprising at least one robot device with at least one movable robot element and at least one actuator for moving the at least one robot element. It is also known to provide at least one relief device for relieving the load on the robot device when the robot system is used in the Earth's gravitational field, wherein at least one force application element is connected to the robot element at at least one coupling point, and at least one force is applied to the robot element, which at least partially compensates for the gravitational force acting on the robot element.

[0005] DE102023128612A1 discloses a robot system with a space robot device comprising at least one movable robot element and at least one actuator for moving the robot element. Furthermore, a support device is provided that supports the robot device during use on Earth. This support device has a force application element that is connected to the robot element at least at one point and exerts at least one force on the robot element that at least partially compensates for the gravitational force acting on the robot element. The support device is designed as a cable robot system that has at least two cable elements connected to the force application element.Each rope element is connected to a motor that can move the respective rope element so that the direction and amount of force applied to the robot element via the force application element can be adjusted.

[0006] DE102023113815B3 describes a method for controlling a robot device having at least one robot element that can be pivoted about at least one first robot joint. The robot element is moved by means of at least one actuator. The actuator is controlled by a first actuator control device, wherein first control signals are sent to the actuator. At the same time, the robot device is supported by a support device that receives second gravity-compensating control signals via a support control device, so that the support device exerts at least one force or moment on the robot element via a force application element connected to the robot element in order to at least partially compensate for the acting gravitational load.To fully compensate for the gravitational force acting on the robot element, not only are gravity-compensating control signals sent to the support device, but also additional gravity-compensating control signals are transmitted from the actuator control device to the actuator.

[0007] DE102017215642B3 relates to a method for controlling a robot with a robot controller and a robot arm controlled by the controller, which comprises several links and joints that connect them in a manner that is adjustable relative to one another. A force compensation device is assigned to the robot arm, which has a mechanical coupling that is coupled to the robot arm to introduce a compensation force generated by the force compensation device into the robot arm. A mathematical model of the force compensation device is provided and used.

[0008] DE102015206121B3 relates to a method for controlling at least one force-controlled manipulator using at least one force compensation device. The method comprises the following steps: determining the magnitude of the compensation force applied to the manipulator by the force compensation device, continuously determining the direction of this compensation force, and controlling the manipulator taking into account the magnitude and direction of the compensation force using a manipulator control device.

[0009] DE102013220798A1 relates to a method for handling objects using at least two industrial robots, each having a manipulator arm with several consecutive links connected by adjustable joints and controlled by at least one control device. One manipulator arm grasps an object and connects it to its end link, while a link of the other manipulator arm is coupled to a link of the first manipulator arm. The invention also includes a corresponding industrial robot.

[0010] DE102011006992A1 relates to a method for the automated movement of a gravity-compensated load body, which is supported by a load body holding means connected to an end effector flange of a robot. A gravity compensation device with a connecting member is provided, which engages a member or the end effector flange of the robot to compensate for the gravity of the load body. The invention also relates to an automated handling system with a gravity compensation device, a load body holding means, and a robot for moving the gravity-compensated load body.

[0011] The object of the present invention is to enable adjustment of the optimal relief force and relief direction.

[0012] To solve this problem, the features of claims 1 and 9

[0013] The invention advantageously provides that the quality of the relief of the robot device is determined by means of the relief device, wherein the relief force used by the relief device and the relief direction of the relief force relative to the robot device are measured and compared by a control device with the desired relief force and a quality value is determined which reflects the quality of the relief, wherein the quality value is a single value for a time step, wherein the quality value is determined as follows: q=(kxΔfx2+kyΔfy2+kzΔfz2)3 where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device, wherein k x , k y , k z definable weighting factors are...

[0014] The present invention has the advantage that the relief force and relief direction can be optimized.

[0015] The control device can determine the quality value using a root-mean-square-errors method.

[0016] The root-mean-square-error method refers to a method used to evaluate the quality of a procedure or model. The root-mean-square-error method is a measure of the difference between the measured values ​​and the specified values.

[0017] The coordinate system with the spatial directions x, y, and z is thus the coordinate system in the space in which the robot device is located. The robot device can move within this space.

[0018] The weighting factors are determined by analyzing the system in question. This analysis may, for example, reveal that a deviation in the x- and y-direction has a greater influence than a deviation in the z-direction. Thus, the weighting factor k would be z set higher than k x and k y .

[0019] The quality of the relief can be calculated for predetermined time steps so that a temporal progression of the relief quality can be output.

[0020] At least one force measuring device can be used to measure the magnitude of the unloading force.

[0021] At least one angle measuring device, preferably two angle measuring devices, can be used to determine the orientation of the relief direction of the relief force relative to the robot device.

[0022] The angle measuring device may preferably be an angle sensor.

[0023] When determining the orientation of the relief direction of the relief force relative to the robot device, the orientation of the robot device at the coupling point with the relief device can be taken into account.

[0024] The control device can calculate the following difference to compare the measured relief force with the desired relief force for the respective relief direction: [ΔfxΔfyΔfz]=ΔF=F−Fdesired where F is the measured force and F gewünscht the desired relief force is, where Δf x , Δf y and Δf z the force difference components for the respective spatial direction x, y, z are, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device.

[0025] The desired relief force and direction can be calculated as follows: F=RR0RA1RA2FKS1 FKS1=[0f0] RA2=[cos(θA2)−sin(θA2)0sin(θA2)cos(θA2)0001] RA1=[cos(θA1)−sin(θA1)0sin(θA1)cos(θA1)0001] where θ A1 the angle measured with the first angle measuring device A1 around a first axis, θ A2 the angle measured with the second angle measuring device A2 around a second axis, where the rotation component R A2 describes the rotation around the second axis, where the rotation component R A1 describes the rotation around the first axis, F KS1 represents the value of the force sensor, where the orientation of the robot device at the coupling point is determined by the coordinate system K S1 is shown.

[0026] The coordinate system K S1 At the coupling point there is a coordinate system that moves along with the robot device.

[0027] According to the present invention, a robot system for calculating the quality of a robot relief device can also be provided, comprising at least one robot device with at least one movable robot element and at least one actuator for moving the at least one robot element, at least one relief device for relieving the robot device when using the robot system in the gravitational field of the Earth, wherein at least one force application element is connected to the robot element at at least one coupling point and at least one force can be applied to the robot element, which at least partially compensates for the gravitational force acting on the robot element, wherein at least one control device is provided which is designed to determine the quality of the relief of the robot device by means of the relief device, wherein the relief force used up by the relief device and the relief direction of the relief force relative to the robot device are measurable and the control device is designed to compare the measured values ​​with the desired relief force and to determine a quality value which reflects the quality of the relief, wherein the quality value is a single value, wherein the control device is designed to determine the quality value as follows: q=(kxΔfx2+kyΔfy2+kzΔfz2)3 where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device, where k x , k y , k z definable weighting factors.

[0028] The control device can be designed to determine the quality value using a root-mean-square-errors method.

[0029] The control device can be designed to calculate the quality of the relief for predetermined time steps, so that a temporal profile of the relief quality can be output.

[0030] At least one force measuring device may be provided to measure the level of the relief force.

[0031] At least one angle measuring device, preferably two angle measuring devices, can be provided to determine the orientation of the relief direction of the relief force relative to the robot device.

[0032] When determining the orientation of the relief direction of the relief force relative to the robot device, the orientation of the robot device at the coupling point with the relief device can be taken into account.

[0033] The control device can be designed to calculate the following difference for comparing the measured relief force with the desired relief force for the respective relief direction: [ΔfxΔfyΔfz]=ΔF=F−Fdesired where F is the measured force and F gewünscht the desired relief force is, where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z are, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device.

[0034] The control device can be designed so that the desired relief force and direction can be calculated as follows: F=RR0RA1RA2FKS1 FKS1=[0f0] RA2=[cos(θA2)−sin(θA2)0sin(θA2)cos(θA2)0001] RA1=[cos(θA1)−sin(θA1)0sin(θA1)cos(θA1)0001] where θ A1 the angle measured with the first angle measuring device A1 around a first axis, θ A2 the angle measured with the second angle measuring device A2 around a second axis, where the rotation component R A2describes the rotation around the second axis, where the rotation component R A1 describes the rotation around the first axis, F KS1 represents the value of the force sensor, where the orientation of the robot device at the coupling point is represented by the coordinate system KS1.

[0035] In the following, an embodiment of the present invention is explained in more detail with reference to the drawings.

[0036] They show schematically Fig. 1 the robot system, Fig. 2 an excerpt from Fig. 1, which shows the force application element, Fig. 3 the control device.

[0037] In Fig. 1 shows a robot system 1. The robot system 1 has a robot device 2. The robot device 2 is preferably a space robot device. The robot device 2 has at least one movable robot element 4. In the present exemplary embodiment, at least three movable robot elements 6, 4 and 8 are provided. The at least one movable robot element 4 can be moved with at least one actuator 13. In the present exemplary embodiment, an actuator 15 is provided which can move the robot element 6. Furthermore, an actuator 13 is provided which can move the robot element 4 and an actuator 11 is provided which can move the robot element 8. Furthermore, joints 14, 12 and 10 are provided around which the respective robot elements 6, 4 and 8 can rotate.

[0038] In the present embodiment, the robot device 2 is preferably a robot arm. Furthermore, the robot device is preferably mounted on a spatially fixed object at location 16. Alternatively, the robot device can also be attached to a movable base.

[0039] The robot system 1 has a relief device 3 which can support the robot device 2 when the robot device is used in the earth's gravitational field. The relief device 3 has at least one force application element 30 which is connected to the at least one robot element 4 at at least one coupling point and to which at least one force can be applied to the at least one robot element 4, which force at least partially compensates for the gravitational force or gravity acting on the one robot element 4. This means that at least a portion of the force exerted on the robot element 4 via the force application element 30 acts against the gravitational force or gravity. By applying the force and partially compensating for the gravitational force or gravity, the robot device 2 is supported or relieved. The robot device 2 should be supported or relieved at least as much.be relieved so that the actuators 10, 12 and 15 can move the robot elements 6, 4 and 8.

[0040] The illustrated relief device 3 is a cable robot system that has at least two cable elements, in the present embodiment four cable elements 18, 20, 22, 24, which are connected to the force application element 30. In the illustrated embodiment, four cable elements 18, 20, 22, and 24 are provided, and each cable element 18, 20, 22, 24 is connected to at least one motor 38, 36, 34, 32, which can move the respective cable element 18, 20, 22, 24. By actuating the respective motor 38, 36, 34, 32, for example, the respective cable element 18, 20, 22, 24 can be rolled up, thus moving the respective cable element 18, 20, 22, 24. At point 48, the four cable elements 18, 20, 22, 24 are connected to a force application cable 26. The force application cable 26 is connected to a force application element 30.Thus, in the illustrated embodiment, the cable elements 18, 20, 22, 24 are indirectly connected to the force application element 30.

[0041] Depending on how tightly the individual cable elements 18, 20, 22, 24 are rolled up, a force is exerted on the force application element 30 and thus on the robot element 4. By adjusting the motors and moving the cable elements 18, 20, 22, 24, the magnitude and direction of the force acting on the force application element 30 and thus on at least one robot element 4 can be adjusted. The cable elements 18, 20, 22, 24 are deflected via deflection elements 41, 43, 45, and 47. The deflection elements 41, 43, 45, and 47 are preferably arranged above the robot element 4.

[0042] At least one force measuring device 28 can be provided to measure the magnitude of the unloading force. The force measuring device 28 can measure the magnitude of the force acting in the force application cable and thus corresponds to the magnitude of the force acting on the robot element 4 and thus relieving it.

[0043] Additionally or alternatively, sensor devices 42, 44, 40, and 46 may also be provided to measure the forces in the cable elements 18, 20, 22, and 24. The total force measurable with the second sensor device 28 may also alternatively be calculated using the forces measured by the sensor devices 42, 44, 40, and 46.

[0044] In an alternative embodiment, the force application cable 26 may be omitted and the cable elements 18, 20, 22 and 24 may be connected directly to the force application element 30.

[0045] The invention is not limited to four cable elements 18, 20, 22, and 24, but can also be implemented with more or fewer cable elements. However, at least two cable elements should be provided so that the direction and magnitude of the force can be varied.

[0046] Furthermore, the coordinate system with the spatial directions x, y, and z is shown. This is the coordinate system in the space in which the robot device 2 is arranged. The robot device 2 can move within this space.

[0047] In Fig. 2 is an excerpt from the Fig. 1, in which the force application element 30 is shown in more detail. The force application element 30 is rotatable about at least a first axis 50 and at least a second axis 52. The first and second axes are preferably substantially orthogonal to one another. Depending on where the robot element 4 is located and how the motors 38, 36, 34, 32 were actuated and thus the cable elements 18, 20, 22, 24 were moved, the force application cable 26 has a different position relative to the robot element 4. The force application element 30 orients itself accordingly.

[0048] The force application element 30 is thus moved passively, depending on the position of the cable elements and the robot element 4. The first axis 50 of the force application element 30 is preferably arranged coaxially with the axis of the robot element 4. At least one first angle measuring device A1 and one second angle measuring device A2 can be provided, which can detect the respective angle about the first and second axes 50, 52 between the force application cable 26 and the robot device 2. This allows the position of the force application cable 26 relative to the robot element 4 to be determined in order to determine the direction in which the applied force acts on the robot element 4 or the robot device 2.

[0049] The quality of the relief of the robot device 2 can be determined by means of the relief device 3, wherein the relief force used up by the relief device 3 and the relief direction of the relief force relative to the robot device 2 is measured and determined by a Fig. 3 is compared with the desired relief force and a quality value is determined which reflects the quality of the relief, wherein the quality value is a single value.

[0050] Furthermore, the coordinate system KS1 is in Fig. 2 shown.

[0051] In Fig.3 shows the control device 204. The measured values ​​of the force measuring device 28 and the first and second angle measuring devices A1, A2 are sent to the control device. The control device can determine the measured relief force and the direction of the relief force based on the measured values. The control device 204 also receives the desired relief force 201 relative to the respective spatial directions. The control device 204 can then determine a quality value 200.

[0052] The quality value can be determined using a root mean-square-errors method.

[0053] The controller 204 can determine the quality value as follows: q=(kxΔfx2+kyΔfy2+kzΔfz2)3 where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device, wherein k x , k y , k z definable weighting factors.

[0054] The weighting factors can be determined in advance by analyzing the system. The weighting factors can be stored in a memory device.

[0055] The quality of the relief can be calculated for predetermined time steps so that a temporal progression of the relief quality can be output.

[0056] The control device can calculate the following difference to compare the measured relief force with the desired relief force for the respective relief direction: [ΔfxΔfyΔfz]=ΔF=F−Fdesired where F is the measured force and F gewünscht the desired relief force is, where Δf x , Δf y and Δf z the force difference components for the respective spatial direction x, y, z are, wherein the force difference components are the difference between the measured relief force and a desired relief force related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device.

[0057] The desired relief force and direction can be calculated as follows: F=RR0RA1RA2FKS1 FKS1=[0f0] RA2=[cos(θA2)−sin(θA2)0sin(θA2)cos(θA2)0001] RA1=[cos(θA1)−sin(θA1)0sin(θA1)cos(θA1)0001] where θ A1 the angle around the first axis measured with the first angle sensor A1 is 50, θ A2 is the angle measured with the second angle sensor A2 around a second axis, where the rotation component R A2 describes the rotation around the second axis 52, where the rotation component R A1 describes the rotation around the first axis 50, F KS1 represents the value of the force sensor, whereby the orientation of the robot device at the coupling point is determined by the coordinate system K S1 is shown.

Claims

[1] Method for calculating the quality of a robot relief device of a robot system (1), wherein the robot system (1) has at least one robot device (2) with at least one movable robot element (4, 6, 8) and at least one actuator (10-13, 15) for moving the at least one robot element (4, 6, 8), wherein at least one relief device (3) is provided for relieving the load on the robot device (2) when the robot system (1) is used in the Earth's gravitational field, wherein at least one force application element (30) is connected to the robot element (4, 6, 8) at at least one coupling point and at least one force is applied to the robot element (4, 6, 8) which at least partially compensates for the gravitational force acting on the robot element (4, 6, 8), characterized by , that the quality of the relief of the robot device (2) is determined by means of the relief device (3), wherein the relief force used up by the relief device (3) and the relief direction of the relief force relative to the robot device (2) are measured and compared by a control device (204) with the desired relief force (201) and a quality value (200) is determined, which reflects the quality of the relief, where the quality value (200) is a single value, wherein the control device (204) determines the quality value (200) as follows: q=(kxΔfx2+kzΔfz2)3 where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z are, wherein the force difference components are the difference between the measured relief force and a desired relief force (201) related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device (2), wherein k x , k y , k z definable weighting factors. [2] Method according to claim 1, characterized by that the control device (204) determines the quality value (200) by means of a root-mean-square-errors method. [3] Method according to claim 1 or 2, characterized by that the quality of the relief is calculated for predetermined time steps so that a temporal progression of the relief quality can be output. [4] Method according to one of claims 1 to 3, characterized bythat at least one force measuring device (28) is used to measure the level of the relief force. [5] Method according to one of claims 1 to 4, characterized by that at least one angle measuring device, preferably two angle measuring devices are used to determine the orientation of the relief direction of the relief force relative to the robot device (2). [6] Method according to claim 5, characterized by that when determining the orientation of the relief direction of the relief force relative to the robot device (2), the orientation of the robot device (2) at the coupling point with the relief device (3) is taken into account. [7] Method according to one of claims 1 to 6, characterized by that the control device (204) calculates the following difference for comparing the measured relief force with the desired relief force (201) for the respective relief direction: [ΔfxΔfyΔfx]=ΔF=F−Fdesired where F is the measured force and F gewünscht is the desired unloading force, where Δf x , Δf y and Δf z the force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force (201) related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device (2). [8] Method according to one of claims 1 to 7, characterized by that the desired relief force (201) and direction is calculated as follows: F=RR0RA1RA2FKS1 FKS1=[0f0] RA2=[cos(θA2)−sin(θA2)0sin(θA2)cos(θA2)0001] RA1=[cos(θA1)−sin(θA1)0sin(θA1)cos(θA1)0001] where θ A1the angle measured with the first angle sensor (A1) around a first axis (50), θ A2 the angle measured with the second angle sensor (A2) around a second axis (52), where the rotation component R A2 describes the rotation around the second axis (52), where the rotation component R A1 describes the rotation around the first axis (50), F KS1 represents the value of the force sensor, wherein the orientation of the robot device (2) at the coupling point is determined by the coordinate system K S1 is shown. [9] Robot system (1) for calculating the quality of a robot relief device, with at least one robot device (2) with at least one movable robot element (4, 6, 8) and at least one actuator (10-13, 15) for moving the at least one robot element (4, 6, 8), at least one relief device (3) for relieving the robot device (2) when using the robot system (1) in the gravitational field of the earth, wherein at least one force application element (30) is connected to the robot element (4, 6, 8) at at least one coupling point and at least one force can be applied to the robot element (4, 6, 8) which at least partially compensates for the gravitational force acting on the robot element (4, 6, 8), characterized by , that at least one control device (204) is provided which is designed to determine the quality of the relief of the robot device (2) by means of the relief device (3), wherein the relief force used up by the relief device (3) and the relief direction of the relief force relative to the robot device (2) are measurable and the control device (204) is designed to compare the measured values ​​with the desired relief force (201) and to determine a quality value (200) which reflects the quality of the relief, wherein the quality value (200) is a single value, wherein the control device (204) is designed to determine the quality value (200) as follows: q=(kxΔfx2+kyΔfy2+kzΔfz2)3 where Δf x , Δf y and Δf zthe force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force (201) related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device (2), where k x , k y , k z definable weighting factors. [10] Robot system (1) according to claim 9, characterized by that the control device (204) is designed to determine the quality value (200) by means of a root-mean-square-errors method. [11] Robot system (1) according to claim 9 or 10, characterized by that the control device (204) is designed to calculate the quality of the relief for predetermined time steps, so that a temporal profile of the relief quality can be output. [12] Robot system (1) according to one of claims 9 to 11, characterized by that at least one force measuring device (28) is provided to measure the level of the relief force. [13] Robot system (1) according to one of claims 9 to 12, characterized by that at least one angle measuring device, preferably two angle measuring devices are provided in order to determine the orientation of the relief direction of the relief force relative to the robot device (2). [14] Robot system (1) according to one of claims 9 to 13, characterized by that when determining the orientation of the relief direction of the relief force relative to the robot device (2), the orientation of the robot device (2) at the coupling point with the relief device (3) is taken into account. [15] Robot system (1) according to one of claims 9 to 14, characterized bythat the control device (204) is designed to calculate the following difference for comparing the measured relief force with the desired relief force (201) for the respective relief direction: [ΔfxΔfyΔfz]=ΔF=F−Fdesired where F is the measured force and F gewünscht the desired relief force (201) is where Δf x , Δf y and Δf z the force difference components for the respective spatial direction x, y, z, wherein the force difference components are the difference between the measured relief force and a desired relief force (201) related to the respective spatial direction x, y, z, wherein the spatial directions x, y, z are spatial directions in a coordinate system related to the robot device (2). [16] Robot system (1) according to one of claims 9 to 15, characterized bythat the control device (204) is designed so that the desired relief force (201) and direction can be calculated as follows: F=RR0RA1RA2FKS1 FKS1=[0f0] RA2=[cos(θA2)−sin(θA2)0sin(θA2)cos(θA2)0001] RA1=[cos(θA1)−sin(θA1)0sin(θA1)cos(θA1)0001] where θ A1 the angle measured with the first angle sensor (A1) around a first axis (50), θ A2 the angle measured with the second angle sensor (A2) around a second axis (50), where the rotation component R A2 describes the rotation around the second axis (52), where the rotation component R A1 describes the rotation around the first axis (50), F KS1 represents the value of the force sensor, wherein the orientation of the robot device (2) at the coupling point is represented by the coordinate system KS1.

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