Device for determining forces acting on a body in at least three spatial directions

Abstract

The invention relates to a device (10) for determining forces acting on a body in at least three spatial directions, comprising two actuating elements (20a, 20b), each of which has an operating element (22a, 22b) with a longitudinal axis (L1, L2), which operating element is movable relative to a base element (24a, 24b), single forces (F1, F2) in at least three spatial directions can be determined as a function of a relative movement between the actuating elements and the base element, and wherein the two actuating elements are arranged relative to each other in such a way that the two actuating elements are arranged on sides (25a, 25b) of the base element facing away from each other; and an evaluation / control unit (30) which detects the individual forces determined by each actuating element and which is designed to calculate forces acting on the body in at least three spatial directions from the two individual forces.

Description

Technical Field

[0001] The invention relates to a device for determining forces acting on a body in at least three spatial directions and to a body having such a device. Background Art

[0002] In order to program and set up operations for a subject, in particular a manipulator such as an industrial robot or Cobot, it is necessary to manually move the subject by applying forces to the subject itself or to corresponding input devices on the subject. Here, in many applications, the sensitivity or the sensitivity of the corresponding input devices for performing the movement is a limiting factor. In addition, current solutions have a sensitivity that depends on the position of the subject due to the measurement principle for detecting the forces.

[0003] Since manipulators usually have different degrees of freedom, controlling all these axes simultaneously in interpolated Cartesian moves in all six degrees of freedom (X, Y, Z, Rx, Ry, Rz) is very important to make the programming process fast and intuitive.

[0004] It is known to measure the motor current required for the movement of the individual axes of the subject, in particular the manipulator, and to calculate from this the torques applied to these axes respectively. By subtracting the required holding torque, the change in the force applied to the axis can be calculated and converted into a subsequent movement. Here, however, the disadvantage is that the force applied to the subject is only measured indirectly. Depending on the position of the subject, in particular the manipulator, leverage effects of different magnitudes can occur, which distribute the sensitivity of the solution unevenly over the entire workspace.

[0005] Alternatively, it is also known to directly measure the torque on the corresponding axis by means of a torque sensor mounted on the axis and to convert the change in torque resulting from the force applied to the axis into a subsequent movement. However, this method also has the disadvantage that the force applied to the body is only measured indirectly and that different amounts of leverage occur depending on the position of the body, in particular the manipulator. In addition, a torque sensor must be attached to each axis, which results in high costs. Summary of the invention

[0006] The object of the present invention is to provide a device for determining forces acting on a body in at least three spatial directions, by means of which the forces exerted on the body can be detected in such a way that a learning process or a programming process of the body can be realized in a simple manner.

[0007] The object of the invention is achieved by a device for determining forces acting on a body in at least three spatial directions having the features of claim 1 .

[0008] Advantageous embodiments and developments of the invention are specified in the dependent claims.

[0009] The device according to the invention for determining the forces acting on a body, in particular a manipulator, in at least three spatial directions has two actuating elements, wherein each of the actuating elements has an operating element with a longitudinal axis, which is movable, in particular tiltable, relative to a base element, wherein individual forces in at least three spatial directions can be determined based on the relative movement between the operating element and the base element, and wherein the two actuating elements are arranged relative to each other in such a way that the two operating elements are arranged on sides of the base element facing away from each other, and the device also includes an evaluation / control unit, which detects the individual forces determined by each actuating element, and the evaluation / control unit is designed to calculate the forces acting on the body in at least three spatial directions based on the two individual forces, in particular based on the sum of the individual forces. Such an actuating element can be operated intuitively. Due to the arrangement of the operating elements on the sides of the base element facing away from each other, the operating elements can be grasped by the user in such a way that the thumb rests on one of the operating elements and, for example, the index finger rests on the other of the operating elements. The user can only move the device in space and perform a learning process or programming process on the body by grasping it in this way.

[0010] The forces acting on the main body can in particular be calculated in at least three linear spatial directions X, Y, Z.

[0011] Advantageously, a single force corresponding to a torque acting around the longitudinal axis of the operating element can be determined based on the relative movement between the operating element and the base element in at least four spatial directions, in particular in three linear spatial directions and in a rotational direction around the longitudinal axis of the operating element, thereby improving the accuracy of determining the force acting on the main body.

[0012] Advantageously, the evaluation / control unit is designed to calculate the forces acting on the body in six spatial directions from the two individual forces, in particular from the sum of the individual forces, in order to further increase the accuracy of the determination of the forces acting on the body.

[0013] Preferably, the two base elements are arranged at a distance A from one another, which makes it possible to determine the forces acting on the body in six spatial directions even if two individual forces in fewer spatial directions are determined.

[0014] According to a preferred development of the invention, each of the actuating elements has an operating element with a longitudinal axis, which is tiltable relative to the base element. The tilting movement can be detected in a simple manner with high precision, while on the other hand the tilting movement can be performed intuitively for the user, so that overall simple operation can result.

[0015] Advantageously, the actuating element is designed in the manner of a joystick or a track point, which allows simple and intuitive operation.

[0016] According to a preferred embodiment of the invention, it is provided that the evaluation / control unit is designed to calculate the forces acting between the two actuating elements in at least three spatial directions based on individual forces, in particular based on the differences of the individual forces. The additional determination of the forces acting between the two actuating elements enables further applications.

[0017] In particular, the device can have an emergency stop switch in a preferred embodiment, which switches depending on the force acting between the two actuating elements. For example, the force acting between the two actuating elements can be compared with a setpoint value and certain events can be triggered if the setpoint value is exceeded or fallen below, such as inhibiting a movement of the subject or activating a learning process or programming process.

[0018] Thus, in one device, both control of the movement of the body based on the determination of the force acting on the body and an emergency stop switch based on the determination of the force acting between two actuating elements can be implemented, both of which can be actuated with a single hand of the user.

[0019] According to a preferred embodiment of the invention, the actuating element, in particular the operating element, is coupled to an actuator, in particular a vibration motor. Such an actuator provides tactile feedback to the user, for example by the actuation performed, by the movement limits of the subject or by the force limits or input limits, thus providing, for example, an indication that the user has applied too much force or torque or that the subject cannot be moved any faster. In principle, different tactile feedback modes can also be provided here in order to report different information to the user.

[0020] The subject according to the invention, in particular a manipulator, preferably an industrial robot or Cobot (collaborative robot), is equipped with the above-described device according to the invention. A so-called Cobot or collaborative robot is an industrial robot that works in collaboration with humans and is not separated from humans by protective devices during the production process. Therefore, in particular in the case of Cobots, corresponding safety functions are provided, which make the interaction between Cobot and user safe.

[0021] Preferably, the two actuating elements are arranged relative to one another on the surface of the body in such a way that their longitudinal axes are arranged parallel to one another. This can simplify the evaluation of the individual forces.

[0022] An advantageous development of the invention provides that the device is arranged detachably on the body, in particular in the form of a module. This enables retrofitting in a simple manner.

[0023] Preferably, the two actuation elements are arranged on two sides of the surface of the main body facing away from each other, so as to enable an ergonomic grip for the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The embodiments of the present invention are described in detail with reference to the following drawings. In the drawings:

[0025] Figure 1 A perspective view showing an embodiment of a device according to the invention for determining forces acting on a body in at least three spatial directions;

[0026] Figure 2 Shown according to Figure 1 A top view of the device;

[0027] Figure 3 Shown according to Figure 1 The device is arranged on a tool storage portion for a robot in a three-dimensional manner;

[0028] Figure 4 Shown according to Figure 3 A top view of the arrangement;

[0029] Figure 5 A perspective view of a portion of a robot arm is shown, on which a Figure 1 Devices;

[0030] Figure 6 Shown according to Figure 5 Another perspective view of a portion of a robotic arm;

[0031] Figure 7 A perspective view of a portion of a robot arm having an integrated device for determining forces acting on a body in at least three spatial directions is shown; and

[0032] Figure 8 Shown according to Figure 7 Another perspective view of a portion of the robotic arm. DETAILED DESCRIPTION

[0033] In all the figures, the same reference numerals denote identical or functionally identical components, wherein, for the sake of a better overview, not all reference numerals are provided in all figures.

[0034] Figure 1 and Figure 2An embodiment of a device 10 for determining forces acting on a body in at least three spatial directions Fx, Fy, Fz, Mx, My, Mz is shown. The spatial directions are three linear directions X, Y, Z and rotations about these three linear directions. If forces acting on a body in three spatial directions are determined, these are in particular the three linear directions X, Y, Z. Preferably, the forces acting on the body in all six spatial directions Fx, Fy, Fz, Mx, My, Mz are determined, i.e. the linear forces Fx, Fy, Fz in the three directions X, Y and Z and the torques My, My, Mz about the three axes.

[0035] The device comprises two actuating elements 20a, 20b, wherein each of the actuating elements 20a, 20b has an operating element 22a, 22b with a longitudinal axis L1, L2, which is movable, in particular tiltable, relative to a base element 24a, 24b. For example, each of the actuating elements 20a, 20b can be constructed in the form of a joystick or a track point. Each base element 24a, 24b has a first side 25a, 25b and a second side 26a arranged substantially parallel to the first side 25a, 25b, wherein the second side of the second base element 20b is hidden in the figure. The operating elements 22a, 22b are particularly arranged on the first side 25a, 25b. The two actuating elements 20a, 20b are particularly constructed in the same structure.

[0036] According to the invention, the two actuating elements 20a, 20b are arranged relative to each other in such a way that the two operating elements 24a, 24b are arranged on the sides 25a, 25b of the base elements 24a, 24b facing away from each other. The other two sides 26a of the base elements 24a, 24b are arranged in particular facing each other. The two actuating elements 20a, 20b are arranged in particular at a distance A from each other.

[0037] The actuating elements 20a, 20b are arranged relative to one another in particular such that the longitudinal axes L1, L2 of the two operating elements 24a, 24b are arranged parallel to one another and in particular coincide (see Figure 2 ).

[0038] The actuation elements 20a, 20b, in particular the operating elements 24a, 24b, can be coupled to an actuator (not shown), in particular a vibration motor, so that tactile feedback can be given on the operating elements 24a, 24b when actuated by a user.

[0039] For each of the actuating elements 20a, 20b, a single force F1, F2 can be determined in at least three spatial directions, in particular at least in three linear spatial directions X, Y, Z, and preferably additionally in a rotational direction Mz around the longitudinal axis L1, L2 of the operating elements 22a, 22b, based on the relative y movement between the operating elements 22a, 22b and the base elements 24a, 24b.

[0040] The device 10 further comprises an evaluation / control unit 30, which detects the individual forces F1, F2 determined by each actuating element 20a, 20b and is designed to calculate the forces acting on the body F in at least three spatial directions, in particular in the three linear spatial directions Fx, Fy, Fz, but preferably in all two spatial directions Fx, Fy, Fz, Mx, My, Mz, from the two individual forces F1, F2. The calculation can be performed, for example, from the sum of the individual forces F1, F2, in particular taking into account the distance A of the two actuating elements 20a, 20b. Even if each individual actuating element 20a, 20b determines individual forces F1, F2 in less than six spatial directions, the fact that two actuating elements 20a, 20b are used and these actuating elements 20a, 20b are arranged spaced apart from one another allows the forces acting on the body F to be calculated overall also in all six spatial directions Fx, Fy, Fz, Mx, My, Mz.

[0041] The evaluation / control unit can also be designed to calculate the force acting between the two actuating elements 20a, 20b in at least three spatial directions, preferably in all six spatial directions Fx, Fy, Fz, Mx, My, Mz, based on the individual forces F1, F2, in particular based on the difference of the individual forces F1, F2, here also in particular taking into account the distance A of the actuating elements 20a, 20b. Here, the force acting between the two actuating elements 20a, 20b can be used, for example, to switch the emergency stop switch 40. Here, the emergency stop switch 40 can be used, for example, to detect whether the user touches the actuating element 20a, 20b and only in this case activate a learning process or a programming process. In the event of too low or too high pressure, the emergency stop switch 40 can stop or prohibit the movement of the body.

[0042] The actuating elements 20a, 20b and the evaluation / control unit 30 can be arranged in a housing 50, which can be releasably arranged on the body. Here, the operating elements 22a, 22b are accessible from the outside of the housing 50 for operation. Here, the operating elements 22a, 22b are arranged in particular on two sides 51, 52 facing each other on the surface of the housing 50. The housing 50 can be fastened by means of fastening means such as screws, magnets, latching connections, etc.

[0043] Figure 3 and Figure 4 The arrangement of the device 10 on a tool receiving portion 60 is shown, the tool receiving portion 60 being, for example, Figure 5 and Figure 6 The robot arm 70 may be arranged on a robot head 72 of a robot arm 70. The robot arm 70 may be a robot arm 70 of an industrial robot or a collaborative robot, a so-called Cobot.

[0044] With such a device 10, the user can learn the movements of the robot arm 70 in a simple manner by gripping in the area of ​​the free end of the robot arm 70, in particular at the robot head 72, where in particular at the tool receptacle 60, and guiding the robot arm 70 in the desired direction, since the device 10 determines the forces applied by the user and acting on the robot arm 70 and can convert them into control signals after the learning process so that the movements can be followed automatically.

[0045] exist Figure 7 and Figure 8 The embodiment shown in differs from the preceding embodiments only in that the device 10 is not detachably arranged on the tool receptacle 60, but is integrated into the tool receptacle 60, i.e. arranged in the same housing. Alternatively, the device 10 can also be integrated into the robot head 72 or another location of the robot arm 70, wherein the device 10 is preferably arranged at the greatest possible distance from the rotation or pivot axis of the robot arm 70, so that the forces required to move the robot arm 70 can be kept low due to the long lever.

[0046] Description of reference numerals:

[0047] 10. Installation

[0048] 20a Actuating element

[0049] 20b Actuating element

[0050] 22a Operating elements

[0051] 22b Operating elements

[0052] 24a Basic components

[0053] 24b Basic components

[0054] 25a side

[0055] 25b Side

[0056] 26a side

[0057] 30 Evaluation / control unit

[0058] 40 Emergency stop switch

[0059] 50 Shell

[0060] 60 Tool Storage

[0061] 70 Robot Arm

[0062] 72 Robot Head

[0063] A Distance

[0064] L1 Longitudinal axis

[0065] L2 Longitudinal axis

Claims

1. A device (10) for determining forces acting on a subject, in particular a manipulator, in at least three spatial directions (Fx, Fy, Fz, Mx, My, Mz), comprising: - two actuating elements (20a, 20b), wherein Each of the actuating elements (20a, 20b) has an operating element (22a, 22b) with a longitudinal axis (L1, L2), the operating element (22a, 22b) being movable, in particular tiltable, relative to a base element (24a, 24b), wherein a single force (F1, F2) in at least three spatial directions can be determined as a function of the relative movement between the operating element (22a, 22b) and the base element (24a, 24b), and wherein the two actuating elements (20a, 20b) are arranged relative to one another in such a way that the two operating elements (22a, 22b) are arranged on sides (25a, 25b) of the base element (24a, 24b) facing away from one another; and - an evaluation / control unit (30), which detects the single forces (F1, F2) determined by each actuating element (20a, 20b), and is configured to calculate the forces acting on the body in at least three spatial directions (Fx, Fy, Fz, Mx, My, Mz) based on the two single forces (F1, F2), in particular based on the sum of the single forces.

2. The device according to claim 1, characterized in that A single force (F1, F2) in at least four spatial directions (Fx, Fy, Fz, Mx, My, Mz), in particular in three linear spatial directions and in a rotational direction around the longitudinal axis (L1, L2) of the operating element (22a, 22b), can be determined based on the relative movement between the operating element (22a, 22b) and the base element (24a, 24b).

3. The device according to any one of the preceding claims, characterized in that The evaluation / control unit (30) is designed to calculate the forces acting on the body in six spatial directions (Fx, Fy, Fz, Mx, My, Mz) based on the two individual forces (F1, F2), in particular based on the sum of the individual forces.

4. A device according to any one of the preceding claims, characterised in that The two base elements (24a, 24b) are arranged at a distance (A) from each other.

5. A device according to any one of the preceding claims, characterised in that The actuating element (20a, 20b) is designed in the manner of a joystick or a track point.

6. A device according to any one of the preceding claims, characterised in that The evaluation / control unit (30) is designed to calculate the forces acting between the two actuating elements (20a, 20b) in at least three spatial directions (Fx, Fy, Fz, Mx, My, Mz) based on the individual forces (F1, F2), in particular based on the differences of the individual forces.

7. A device according to any one of the preceding claims, characterised in that The device (10) has an emergency stop switch (40) which switches depending on the force acting between the two actuating elements (20a, 20b).

8. A device according to any one of the preceding claims, characterised in that The actuating element (20a, 20b), in particular an operating element (22a, 22b), is coupled to an actuator, in particular a vibration motor.

9. A body, in particular a manipulator, preferably an industrial robot or a Cobot (collaborative robot), having a device (10) according to any of the preceding claims.

10. The body according to claim 9, characterized in that The two actuating elements (20a, 20b) are arranged relative to each other on the surface of the body in such a way that their longitudinal axes (L1, L2) are arranged parallel to each other.

11. The body according to claim 9 or 10, characterized in that The device (10) is releasably arranged on the body.

12. A body according to any one of claims 9 to 11, characterized in that The two actuating elements (20a, 20b) are arranged on two sides of the surface of the body facing away from each other.

Images