Method for automatically setting safety function configuration for robotic device

Abstract

The invention relates to a method (100) for automatically setting a safety function configuration for a robotic device (50), comprising:-obtaining (102) distance information (4), the distance information (4) being a distance between at least one moving part (52) of the robotic device (50) and a defined point of position (3) in an environment (2) of the robotic device (50); -comparing (104) the distance information (4) with a minimum clearance criterion, the minimum clearance criterion defining a minimum distance between at least one moving part (52) of the robotic device (50) and a defined position point (3) in the environment (2) of the robotic device (50),-determining (104) the distance information (4) as a function of a deviation of the distance information (4) from the minimum clearance criterion, a corresponding safety function configuration in the dedicated workspace region for the robotic device (50) is automatically determined (106).

Description

Technical Field

[0001] The present invention relates to a method for automatically setting a safety function configuration for a robotic device. Background Art

[0002] In collaborative robotics applications, physical contact between humans and mobile robots cannot be avoided, and power and force limiting (PFL) protection measures must be used to properly control potential contact situations so that they are harmless to humans.

[0003] Because the contact mechanics of a robotic device differ significantly between a crush situation and a free impact, adequately reducing the risk of each of these contact types requires implementing different measures or restrictions on the motion of the robotic device.

[0004] Therefore, the risk assessment must identify potential contact hazards and differentiate them with respect to their contact configuration, which can be constrained (clamping, crushing) or unconstrained (free impact, collision). Depending on the contact configuration, different safety functions or safety parameters must be applied to the robotic equipment to ensure appropriate risk mitigation.

[0005] Furthermore, risk assessments of robotic equipment must therefore identify and differentiate between areas within the robot's range of motion where there is a risk of pinching or crushing ("pinching zones") and areas where unrestrained contact is possible due to the absence of structural obstacles, allowing for free recoil of human body parts.

[0006] Preemptively limiting the manipulator's speed and thus its kinetic energy to a certain extent can substantially reduce the risk in unrestrained contact situations. In contrast, protection against crushing or pinching hazards usually requires considerably lower robot speeds and a limitation of the maximum contact force that the robot can exert.

[0007] It is therefore crucial for operator safety that robotic equipment adhere to these limits where these hazards exist, while in other cases it is desirable to utilize less stringent limits to protect free impact in order to avoid unnecessary productivity losses.

[0008] For this purpose, the robotic device requires information defining in which areas (or during which phases of the application) a crushing hazard has to be taken into account and in which areas only free impacts can occur.

[0009] Currently, this is typically achieved by manually defining spatial zones in the safety configuration of the robotic device and assigning corresponding safety functions and parameters (e.g., speed and force supervision with corresponding limits). However, manual configuration of the safety functions of the robotic device has the following major drawbacks: the robotic device's safety zones cannot automatically adapt to changes in the robotic application, such as new crush hazards introduced by installing additional features on the robotic device or in its environment; or to dynamically changing environmental requirements of the robotic device, such as vision-based applications where the workpiece position is not predefined. This makes the safety configuration of the robotic device cumbersome and the entire production process involving the robotic device expensive and time-consuming.

[0010] These issues need to be addressed. Summary of the Invention

[0011] Therefore, it would be advantageous to provide an improved concept for automatically generating a safety function configuration for a robotic device that is dynamically applied to different production scenarios of the robotic device.

[0012] The objects of the invention are solved by the subject-matter of the independent claims, wherein further embodiments are incorporated in the dependent claims.

[0013] In a first aspect of the present invention, there is provided a method for automatically setting a safety function configuration for a robotic device, comprising the following steps:

[0014] - obtaining distance information, wherein the distance information is at least one moving part of the robotic device

[0015] The distance between the component and a defined location point in the environment of the robotic device;

[0016] - comparing the distance information with a minimum clearance criterion, the minimum clearance criterion defining a minimum distance between at least one mobile component of the robotic device and a defined location point in the environment of the robotic device,

[0017] - Automatically determining a corresponding safety function configuration in a dedicated workspace area for the robotic device based on the distance information and the deviation from the minimum clearance standard.

[0018] In other words, the core idea behind the present invention is to use information about the application environment of the robotic device, or more specifically, to use information about the distance between the robotic device (including its end effector) and the application environment of the robotic device to automatically configure the safety function configuration of the robotic device, which safety function configuration includes defining at least one safety zone around the robotic device.

[0019] By comparing distance information obtained, for example, from an environment model and / or recorded via a sensor system connected to the robotic device or providing sensory information to the robotic device (for example during a commissioning run) with the minimum clearance criteria, areas where there is a risk of crushing can be easily identified and the required safety zone can be automatically set in the safety configuration of the robotic device.

[0020] A further distinction can be made by considering only accessible areas of the robot device's workspace, since there is no risk of physical contact in areas where access by humans is prevented (by protective measures such as fences or other physical barriers). Therefore, there is no need to limit the robot's speed in defined areas of the robot's workspace that are inaccessible to humans.

[0021] As an alternative to the present invention, if safety-rated distance information is available during runtime of the application, this can be utilized to switch directly between the settings required to protect different contact types, thereby avoiding the need to set up safety zones altogether.

[0022] The present invention is advantageous in that it simplifies PFL-related configuration for robotic devices. Furthermore, the present invention significantly improves ease of use for users of all experience levels when configuring safety features for robotic devices, and reduces the time and cost of manually adapting safety feature configurations for robotic devices as the environment and / or application of the robotic device dynamically change.

[0023] According to one example, the distance information is obtained by at least one sensor system, wherein the at least one sensor system provides at least one piece of information, the at least one piece of information being one of environmentally relevant information about the environment of the robotic device and / or an exposed body area of ​​a person in a dedicated workspace area of ​​the robotic device. This achieves the following advantage: a more detailed safety function configuration for the robotic device can be applied to the robotic device that better complies with the environment of the robotic device, thereby resulting in more efficient operation of the robotic device.

[0024] According to one example, the distance information is safety-relevant distance information provided by at least one sensor system. Thereby, the advantage of generating a safety function configuration of the robotic device in an efficient manner is achieved.

[0025] According to one example, the sensor system is a robot-internal sensor system applied directly to the robotic device and / or the sensor system is a robot-external sensor system applied to the robotic device at a distance. The following advantage is achieved: sensory information is provided to the robotic device in an efficient manner depending on the environment or application of the robotic device.

[0026] According to one example, the distance information is obtained solely from a mathematical 3D model of the robotic device, or the 3D model additionally includes context-related information about the environment of the robotic device. This has the advantage of generating a more realistic and optimized safety function configuration for the robotic device, allowing the robotic device to be operated in an efficient and optimized manner.

[0027] According to one example, actual geometrical parameters of at least one moving part of the robotic device are used to obtain distance information. In this way, the advantage of obtaining accurate distance information is achieved, resulting in an optimal or optimised safety function configuration of the robotic device.

[0028] According to one example, a defined buffer area around at least one moving part of the robotic device is used to obtain distance information. The following advantage is achieved: when calculating distances configured for safety functions of the robotic device, the calculation or processing load can be reduced.

[0029] According to one example, distance information is acquired during operation of the robotic device during production mode. The resulting advantage is that the safety function configuration of the robotic device can be adapted without stopping the operation of the robotic device or optimizing the operation of the robotic device's production process. In this case, the use of safety-rated sensors is desirable because the robotic device's controller will automatically enable or disable certain safety functions based on this information.

[0030] According to one example, distance information is obtained during a trial run of a programmed production cycle of a robotic device deployed in an environment, which is an application environment. The advantage achieved is that a safety configuration is automatically generated and a safety zone around the robotic device is automatically set. Another advantage is that before the robotic device is used in a specific production scenario, for example before it is used by an external customer at another work site or production site, the safety function configuration can be adapted to the needs of the user. In addition, the application design can be tested and adjusted accordingly. In the above-mentioned trial run scenario, the sensor system does not need to have safety-related sensors to obtain the distance information, resulting in a less complex and cost-effective robotic device.

[0031] According to one example, determining a safety function configuration includes flexibly applying at least one safety function to the robotic device based on at least one of a position parameter of the robotic device, an adaptation function of the robotic device, or an adaptation environment parameter of the robotic device, wherein the adaptation environment parameter includes environmental information of an environment within a dedicated workspace area of ​​the robotic device. Advantageously, when combined with the environment of the robotic device, a more customized safety function configuration for the robotic device can be applied to the robotic device, thereby achieving optimized production operation of the robotic device.

[0032] According to one example, the step of determining a safety function configuration includes setting at least one safety zone around the robotic device, the at least one safety zone having at least one dedicated safety function corresponding to a deviation of the obtained distance information from a minimum clearance standard. This advantageously allows for generating a customized safety zone around the robotic device in an efficient manner adapted to the detected environment of the robotic device.

[0033] According to one example, the at least one safety zone is flexibly configurable based on at least one geometric parameter of at least one moving component of the robotic device and / or a parameter of a detected environment of the robotic device. This provides the advantage that a customized safety zone around the robotic device can be generated in an efficient manner adapted to the detected environment of the robotic device.

[0034] According to one example, the at least one safety zone includes an overlap portion resulting from an intersection of a dedicated workspace area of ​​the robotic device and an area accessed by a person. Advantageously, a customized safety zone can be efficiently generated, thereby maximizing the workspace area of ​​the robotic device and resulting in optimized operation of the robotic device.

[0035] In a second aspect of the present invention, a computer is provided, comprising a processor configured to execute the method of the preceding aspect.

[0036] In a third aspect of the present invention, there is provided a computer program product comprising instructions which, when executed by a processor of a computer, cause the computer to perform the method of any one of the first and second aspects.

[0037] In a fourth aspect of the invention, a machine-readable data medium and / or download product comprises the computer program of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Exemplary embodiments will be described below with reference to the following drawings:

[0039] Figure 1 A schematic flow chart of the method of the present invention is shown;

[0040] Figure 2 A schematic example of automatic safety zone configuration according to the method of the present invention is shown;

[0041] Figure 3 A schematic example of an automatic safety zone configuration with sensors on a robotic device according to the method of the present invention is shown; and

[0042] Figure 4 Schematic example showing overlapping safety zone configuration according to the method of the present invention DETAILED DESCRIPTION

[0043] Figure 1 A schematic flow chart of a method 100 of the present invention is shown.

[0044] In a first step 102, distance information 4 is obtained, wherein the distance information 4 is a distance between at least one mobile component 52 of the robotic device 50 and a defined location point 3 in the environment 2 of the robotic device 50. Alternatively, the distance information 4 can also be considered as a minimum distance between the at least one mobile component 52 of the robotic device 50 and an object in the environment 2 of the robotic device 50.

[0045] In this regard, it is worth noting that the defined location point 3 is the point or location in the environment 2 of the robotic device 50 that is closest to or in close proximity to the robotic device 50. Furthermore, it should be noted that the environment 2 of the robotic device 50 also means one or more objects in the environment 2 of the robotic device 50.

[0046] In a second step 104 , the distance information 4 is compared with a minimum clearance criterion, which defines a minimum distance between the at least one mobile part 52 of the robotic device 50 and a defined position point 3 in the environment 2 of the robotic device 50 .

[0047] In a third step 106 , a corresponding safety function configuration in the dedicated workspace area for the robotic device 50 is automatically determined based on the distance information 4 and the deviation from the minimum clearance criterion.

[0048] In this way, the present invention allows automatic determination of the position and size of the required safety zone around the robotic device 50. Within the safety zone with a distance below the minimum clearance, the restrictions required for safety functions and protection against crush situations will be automatically applied.

[0049] Optionally, the step 106 of determining a safety function configuration includes flexibly applying at least one safety function to the robotic device 50 according to:

[0050] - at least one of the position parameters of at least one robotic device 50,

[0051] - an adaptation function of the robotic device 50, or

[0052] - Adaptation environment parameters of the robotic device 50, wherein the adaptation environment parameters include the dedicated workspace area 54 of the robotic device 50 (see Figure 4 ) in the environment 2.

[0053] Figure 2 A schematic example of an automatic safety zone configuration according to the method of the present invention is shown. Figure 2In the embodiment of the present invention, the sensor system 30 is a robot-external distance (proximity) sensor 34 , which provides distance information 4 between a mobile part 52 of the robotic device 50 and a defined position point 3 in the environment 2 of the robotic device 50 .

[0054] Then the Figure 2 The distance information 4 obtained by the sensor 34 in is compared with a minimum clearance criterion which defines a minimum distance between a mobile part 52 of the robotic device 50 and a defined position point 3 in the environment 2 of the robotic device 50 .

[0055] The sensor system 30 provides at least one piece of information, which is context-related information about the environment 2 of the robotic device 50 and / or the dedicated workspace area 54 of the robotic device 50 (see Figure 4 ) is one of the information of the exposed body area of ​​the person.

[0056] exist Figure 2 The corresponding safety function configuration for the robotic device 50 , schematically indicated in FIG. 5 by a safety zone 56 in the dedicated workspace area around the robotic device 50 , depends on the distance information 4 and the deviation of the minimum gap criterion.

[0057] For example, appropriate minimum clearances to prevent crushing of different body parts are specified in ISO 13854 (e.g. ≥ 120 mm to prevent crushing of a human arm); the dimensions of the automatically configured areas should additionally include margins to take into account the robot's reaction and stopping distance in the event of a fault. In areas with distances greater than the corresponding minimum clearances, less stringent limits for protecting against free impact are applied. For both types of contact, assumptions about the potentially exposed human body areas are needed to determine appropriate robot motion limits, in particular the maximum speed and the maximum contact force. In most cases, it will be sufficient to resort to worst-case assumptions, e.g. selecting parameters for crushing based on the biomechanical limits for hands and fingers of ISO / TS 15066 / unconstrained contact for the human chest.

[0058] like Figure 2 and Figure 4 The safety zone 56 shown is optionally flexibly configurable based on at least one geometric parameter or actually detected geometric parameters of the mobile part 52 of the robotic device 50. Alternatively, detected environmental parameters of the robotic device 50 can also be used to configure the safety zone 56.

[0059] The geometric parameters, detected environmental parameters or environment-related parameters may include information on additional technical features, such as a new tool device installed at the robotic device 50, which changes the moving radius of the robotic arm (moving part) of the robotic device 50 or / and the geometric shape of the robotic arm.

[0060] However, the detected environmental parameters may also be applied when obstacles in the robot's environment change (are added or removed), and this environmental related information is then transmitted to the robotic device for configuring a new safety function configuration or a safety zone around the robotic device 50.

[0061] exist Figure 2 , the moving part 52 of the robotic device 50 has a practically definable buffer area 53 applied to or located around a limited or defined space or area of ​​the moving part 52 of the robotic device 50. The buffer area 53 can be considered as an encapsulation of the moving part 52 of the robotic device 50 and allows the required distance information 4 to be obtained in an easier manner and helps to reduce the processing load when obtaining the distance information 4.

[0062] The distance information 4 can be obtained in two different operating scenarios or operating modes of the robotic device 50 .

[0063] In the first operating mode, distance information 4 is obtained at runtime during the production mode of the robotic device 50. During the runtime mode, it is necessary to use safety-grade sensors in the sensor system 30, as the controller of the robotic device 50 will automatically enable / disable safety functions based on this safety information. In this regard, the obtained distance information 4 is safety-relevant distance information 4 provided by the sensor system 30. Furthermore, in the runtime mode, the distance between the mobile part 52 of the robotic device 50 and any obstacles or the environment 2 can be permanently monitored.

[0064] Then, if the measured distance is below the minimum clearance, this information is used to switch directly to the stricter "squeeze" safety configuration setting, without the need for a predefined zone or environmental model. It should be noted again that the sensors used for this purpose must provide safety-level information about the distance (or at least about the presence or absence of obstacles within the configured minimum clearance). Furthermore, information about the exposed body area is useful and mandatory when operating the robotic device at runtime, such as when worst-case scenarios are assumed or specified by the operator.

[0065] Permanent distance monitoring will then advantageously allow the robot motion to automatically adapt to changes in the application environment without the need for reconfiguration, making this method also suitable for applications in which the robot path is not predefined, for example, if the motion is adjusted based on input from sensors such as vision systems. Note that after this method, collisions with the robot using the "free impact" restriction are completely prevented, since a human body part approaching closer than the minimum clearance will also trigger a switch to the "squeeze" restriction. It can therefore be interpreted as a combination of the protection principle PFL with speed and separation monitoring (SSM).

[0066] In the second operating mode, the distance information 4 is obtained during a commissioning of a programmed production cycle of the robotic device 50 deployed in the environment 2 , which is the application environment in this operating mode.

[0067] Furthermore, the distance information 4 can also be obtained during the simulation of a programmed production cycle in a simulation environment.

[0068] During commissioning, the use of the distance information 4 recorded during the test run only supports users who have configured a safety zone for the robotic device 50. Therefore, any (also non-safety-rated) sensor in the sensor system 30 can be used. Therefore, the user is responsible for verifying and applying the generated safety configuration of the robotic device 50.

[0069] The distance information may be obtained by using a mathematical 3D model of the robotic device 50. The 3D model also includes context-related information of the environment 2 of the robotic device 50, such as barriers, obstacles near the robotic device 50 or in the workspace domain of the robotic device 50.

[0070] The 3D model of the robotic device 50 may be a CAD model from the engineering phase of the robotic device. Alternatively, the 3D model may be built based on sensor data from a physical robotic station, using, for example, a 3D camera system, LIDAR or photogrammetry. Based on this model, distance information between the geometry of the manipulators of the robotic device (including tools, workpieces) and the environment 2 may be extracted for programming robotic movements of the robotic device 50. When calculating the distances, the actual geometry of the moving parts of the robot linkages, tools or workpieces may be disregarded, and alternatively, information such as Figure 2 The geometric primitives of the buffer area 53 in (which encapsulates the moving parts 52 of the robotic device 50) are used to reduce the computational load.

[0071] Figure 3 A schematic example of an automatic safety zone configuration with sensors on a robotic device according to the method of the present invention is shown.

[0072] Figure 3 The robotic device 50 in FIG. 5 comprises a sensor system 30 having a plurality of robot-internal distance (proximity) sensors 32 mounted at various locations on the robotic device 50. Distance information 4 can then be obtained only during commissioning (for offline automatic configuration of zones) or permanently in the deployed application (online) for automatic switching between different safety functions / parameters (no zone configuration required).

[0073] Figure 4 A schematic example of an overlapping safety zone configuration according to the method of the present invention is shown. Figure 4An area 58 accessed by a person and a workspace area 54 of the robotic device 50 are shown. The intersection between the two areas is an overlap portion 57 corresponding to the workspace area 56 of the robotic device 50.

[0074] The overlap area portion 57 can be applied, for example, to the following situation: if a 3D model of the robotic device or robotic station 50 is available, which may include environmentally relevant information 2 about obstacles that limit a person's reach (e.g., barriers, robots mounted on tables), then safety distances can be applied, for example, according to ISO 13857, to determine areas that can be safely accessed by a person without the risk of contact with the robotic device 50. By creating a spatial representation of the area 58 accessed by a person, the intersection 57 with the robot workspace 54 can be determined and used to set a configured and optimized safety zone only in the overlap area. Optionally, in the process of finding the overlap area portion 57, anthropometric data of different body parts can be utilized (e.g., compared with EN547-3) to determine the exposed body parts and comply with their corresponding restrictions from ISO / TS15066. In this way, a customized and optimal safety zone for the robotic device can be configured in an efficient manner.

[0075] Reference numerals

[0076] 100 methods

[0077] 102 Obtain

[0078] 104 Comparison

[0079] 106 OK

[0080] 2 Environment / Obstacles of the Robotic Device

[0081] 3 location points

[0082] 4 Minimum distance between the robot device and the environment

[0083] 30 sensor systems

[0084] 32 Robot-Internal Distance Sensor

[0085] 34 Robot-External Distance Sensor

[0086] 50 robotic equipment

[0087] 52 (Mobile) parts of robotic equipment

[0088] 53 Buffer Zone

[0089] 54 Workspace Area

[0090] 56 Safe Zone

[0091] 57 Overlapping area

[0092] 58 people visited the area

Claims

1. A method (100) for automatically setting a safety function configuration for a robotic device (50), comprising: - obtaining (102) distance information (4), wherein the distance information is a distance between at least one mobile component (52) of the robotic device (50) and a defined position point (3) in an environment (2) of the robotic device (50); - comparing (104) the distance information (4) with a minimum clearance criterion defining a minimum distance between the at least one mobile part (52) of the robotic device (50) and the defined location point (3) in the environment (2) of the robotic device (50), - automatically determining (106) a corresponding safety function configuration in a dedicated workspace area for the robotic device (50) based on a deviation of the distance information (4) from the minimum gap standard.

2. The method (100) according to claim 1, wherein the distance information (4) is obtained by means of at least one sensor system (30), wherein the at least one sensor system (30) provides at least one information, the at least one information being one of environmental related information of the environment (2) of the robotic device (50) and / or an exposed body area of ​​a person in a dedicated workspace area (54) of the robotic device (50).

3. The method (100) according to any one of the preceding claims, wherein the distance information (4) is safety-relevant distance information (4) provided by the at least one sensor system (30).

4. The method (100) according to claim 2 or 3, wherein the sensor system (30) is a robot internal sensor system (32) applied directly to the robot device (50) and / or the sensor system (30) is a robot external sensor system (34) applied to the robot device (50) at a certain distance.

5. A method (100) according to any one of the preceding claims, wherein the distance information (4) is obtained solely from a mathematical 3D model of the robotic device (50), or wherein the 3D model additionally includes the environment-related information of the environment (2) of the robotic device (50).

6. The method (100) according to any one of the preceding claims, wherein actual geometrical parameters of the at least one moving part (52) of the robotic device (50) are used to obtain the distance information (4).

7. The method (100) according to any of the preceding claims, wherein a defined buffer area (53) around at least one mobile part (52) of the robotic device (50) is used to obtain the distance information (4).

8. The method (100) according to any one of the preceding claims, wherein the distance information (4) is obtained at runtime during a production mode of the robotic device (50).

9. The method (100) according to any one of the preceding claims 1 to 7, wherein the distance information (4) is obtained during a commissioning of a programmed production cycle of the robotic device 50 deployed in the environment (2), the environment (2) being an application environment.

10. The method (100) according to any one of the preceding claims, wherein the step of determining (106) the safety function configuration comprises: At least one safety function is flexibly applied to the robotic device (50) based on at least one of the position parameters of the at least one robotic device (50), the adaptation function of the robotic device (50), or the adaptation environment parameters of the robotic device (50), wherein the adaptation environment parameters include the environmental information of the environment (2) in the dedicated workspace area (54) of the robotic device (50).

11. The method (100) according to any one of the preceding claims, wherein the step of determining (106) the safety function configuration comprises: At least one safety zone (56) is provided around the robotic device (50), the at least one safety zone (56) having at least one dedicated safety function corresponding to the deviation of the obtained distance information (4) from the minimum gap standard.

12. A method (100) according to claim 10 or 11, wherein the at least one safety zone (56) is flexibly configurable based on at least the geometric parameters of the at least one moving part (52) of the robotic device (50) and / or the detected environmental parameters of the robotic device (50).

13. The method (100) of claim 10, wherein the at least one safety zone (56) includes an overlap portion (57) that is the result of the dedicated workspace area (54) of the robotic device (50) intersecting with an area (58) accessed by humans.

14. A computer comprising a processor configured to perform the method according to any one of the preceding claims 1 to 13.

15. A computer program product comprising instructions which, when executed by a processor of a computer, cause the computer to perform the method according to any one of claims 1 to 13.

16. A machine-readable data medium and / or download product comprising a computer program according to claim 15.

Images