Method for testing a radio connection between a mobile robotic system and an external control unit
Patent Information
- Application Number
- EP2023789579
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-10-11
- Filing Date
- 2023-10-11
- Publication Date
- 2025-08-20
AI Technical Summary
Current methods for testing radio connections in mobile robotics systems fail to effectively simulate complex interference scenarios and create realistic test environments, particularly for scenarios like earthquakes or floods that significantly alter communication conditions.
A method involving the creation of a digital twin of a real environment with modeled material properties, using external positioning systems to track the mobile robotics system's position, and adjusting radio signals based on simulated propagation to replicate complex interference scenarios cost-effectively.
Enables the reproducible and accurate testing of radio connections in complex environments, accounting for various material properties and interference, ensuring reliable communication under challenging conditions.
Smart Images
Figure 1.1
Abstract
Description
[0001] Method for testing a radio connection between a mobile robotic system and an external control unit
[0002] The invention relates to a method for testing a radio connection between a mobile robotic system and an external control unit in a real environment.
[0003] Mobile robotics systems, particularly automated guided vehicles for logistics, robots for rescue or research missions, and partially or fully automated motor vehicles, must undergo extensive testing for approval or certification. Until now, the focus of testing procedures, particularly for automated guided vehicles or robots, has primarily been on the mechanical and sensory properties of the robotic systems. This means that a mobile robotic system must perform certain tasks within a predefined scenario, such as navigating a course with ramps and stairs or opening a door and closing a valve. Typically, these tasks are not performed entirely autonomously by the mobile robotic system. Rather, they are controlled by a so-called operator, who specifies the tasks and can also directly control certain operations remotely.In this respect, a mobile robotic system must not only possess mechanical and sensory capabilities, but also have a sufficiently stable radio connection to the operator or an external control unit. Verifying the radio connection under challenging conditions is also playing an increasing role in the certification of partially or fully automated motor vehicles.
[0004] Traditionally, however, such test procedures only consider simple interference scenarios. These include, for example, a complete communication failure, an increased packet error rate, or various shadowing obstacles, which are far removed from realistically modeled scenarios, such as those that occur in the event of an earthquake or flooding due to the destruction of infrastructure. In such cases, completely different communication conditions arise, which the mobile robotic systems must cope with. The state-of-the-art methods for testing a radio connection in a mobile robotic system do not yet allow for complex interference scenarios to be considered while simultaneously creating a realistic test environment.
[0005] Based on this, the object of the invention is to provide a method for testing a radio connection of a mobile robotic system in a real environment, which enables testing of the radio connection in an arbitrarily modeled test environment so that even complex interference scenarios can be simulated cost-effectively.
[0006] This problem is solved by the subject matter of patent claim 1. Preferred developments can be found in the subclaims.
[0007] According to the invention, a method is provided for testing a radio connection between a mobile robotic system and an external control unit in a real environment, wherein the real environment has at least one three-dimensional structure with predetermined material properties, the mobile robotic system and the external control unit each have a communication unit with at least one antenna for transmitting and / or receiving a radio signal, with the following method steps:
[0008] 51) Capturing the real environment and creating a virtual environment, where the virtual environment is a digital twin of the real environment,
[0009] 52) Modelling the virtual environment using a planning system by emulating the material properties of the entity of the virtual environment and / or adding further three-dimensional entities with predetermined material properties to the virtual environment,
[0010] 53) Detecting a position of the mobile robotic system in the real environment by means of an external positioning system,
[0011] 54) Transferring the position of the mobile robotic system in the real environment to the virtual environment,
[0012] 55) Modeling a radio propagation of a test signal in the modeled virtual environment depending on the position of the mobile robotic system in the virtual environment, 56) Determining change parameters for adapting a radio signal of the radio link in the real environment according to the modeled test signal in the virtual environment, and
[0013] 57) Adjusting the radio signal according to the change parameters and sending the adjusted radio signal to the mobile robotics system or the external control unit.
[0014] When we talk about a real environment in this context, we mean a test area on which one or more three-dimensional structures can be arranged. These include, in particular, buildings of different heights or widths, staircases, ramps, or simple walls. These three-dimensional structures exhibit physical material properties, such as density or surface characteristics. Depending on the material, they can shield or reflect a radio signal differently. For example, a wooden wall is less problematic for radio communication than a concrete wall.
[0015] In this context, a digital twin is understood as a digital representation of a tangible or intangible environment from the real world in the digital world. It is irrelevant whether the counterpart already exists in the real world or will only exist in the future. The digital twin enables comprehensive data exchange. It consists of a model of the represented environment and can also contain simulations, algorithms, and services that describe or influence the properties or behavior of the represented environment.
[0016] When we talk about the position of the mobile robotic system in the real environment, we mean the location of the mobile robotic system within the real environment. The position is determined using an external positioning system. In this case, this refers to an independent positioning system. This means that the position is determined independently of the position determined by the mobile robotic system itself. The independent positioning system can, for example, be a satellite-based system or a camera with the test environment located in its field of view.The external and independent positioning system enables appropriate reproducibility of the precise positioning of the mobile robotic system as an input parameter for the digital twin, which is essential for reproducible testing of a radio link with high accuracy in very complex and differentiated representations of real environments.
[0017] Radio propagation modeling specifically involves tracking emitted radio waves from a specific position within the virtual environment. This takes into account shadowing and reflections of the radio waves from three-dimensional structures and continues to track them even after they hit different surfaces.
[0018] When we talk about adapting the radio signal in this context, we specifically mean attenuating the radio signal. This means that the existing real radio signal is physically attenuated, reducing its signal strength and adapting it to the test signal in the virtual environment. Attenuation of the signal can even be so severe that it is completely suppressed and thus no longer available.
[0019] A key aspect of the invention is therefore that the modeled mechanical environments of a test site can be overlaid with a highly realistic model of the radio-technical properties of different material properties of the environment. Even if the mechanical environment provided for the mobile robotic system for testing purposes was realized with materials that have little radio interference, such as wood and plastic, an environment consisting of stone, concrete, and / or metal, for example, can be emulated and / or supplemented with radio technology and thus integrated into the test scenario in a realistic and cost-effective manner.
[0020] According to a preferred development of the invention, the method comprises the following further method steps:
[0021] 58) Moving the mobile robotic system in the real environment, and
[0022] 59) Repeat steps S3) to S7) in real time.
[0023] In this context, "moving" refers to changing the position or location of the mobile robotic system within the real environment. This occurs primarily through movements of the mobile robotic system, so that the mobile robotic system has a new location, and from there, a new modeling and adaptation of the radio signal takes place.
[0024] Radio propagation is preferably modeled using ray tracing. Ray tracing is an algorithm based on the emission of rays for calculating occlusion, i.e., for determining the visibility of three-dimensional objects from a specific point in space. Ray tracing also refers to several extensions of this basic method that calculate the further path of rays after they hit surfaces.
[0025] According to a preferred development of the invention, the position of the mobile robotic system in the real environment is detected using GNSS, UWB radio, and / or external optical sensors. GNSS is a global navigation satellite system for positioning and navigation on Earth and in the air by receiving signals from navigation satellites and pseudolites. This system is particularly suitable for outdoor use. Indoors, positioning is determined in particular using UWB radio or optical sensors. UWB radio is a possibility for short-range radio communication using ultra-wideband technology. An important feature is the use of very large frequency ranges with a bandwidth of at least 500 MHz or at least 20% of the arithmetic mean of the lower and upper limit frequencies of the used frequency range.
[0026] According to a preferred embodiment of the invention, at least one communication unit has electronically controllable attenuators for attenuating the radio signal. The input level of the radio signal can then be adjusted according to the change parameters, and the signal can be transmitted to the communication unit with appropriate physical attenuation by means of corresponding electronically controllable attenuators.
[0027] According to a preferred embodiment of the invention, the radio connection is associated with a first radio system. The method then comprises the following further method steps: S2a) emulating the first radio system of the radio connection using the planning system, and
[0028] S5a) determining signal properties of the test signal, wherein the test signal is associated with a second radio system different from the first radio system, and S6a) adapting the signal properties of the radio signal of the first radio system in the real environment according to the signal properties of the test signal of the second radio system.
[0029] The determined physical signal properties of the radio signal are derived, depending on a given radio system, into communication performance indicators such as data rate, packet error rate, and / or latency using appropriate simulation models. These are then implemented for another radio system using appropriate software at the operating system level. Further preferred options include WLAN, LTE, 5G, or 6G. These developments therefore make it possible to reproducibly transfer and / or test the behavior or influence of radio channel properties to other radio systems, such as LTE or 5G mobile communications.
[0030] According to a preferred development of the invention, the method comprises the following further method step:
[0031] S5') Modeling a noise signal and adding the noise signal to the test signal.
[0032] In this way, potential interference signals generated by other radio equipment in the scenario, such as public radio systems or deliberate jammers, can also be taken into account and their effects, such as an increased packet error rate, can be integrated via the change parameters transmitted to the communication units.
[0033] The invention further provides for the use of the method described above for testing and / or certifying mobile robotic systems. The mobile robotic systems are preferably semi-autonomous or autonomous rescue robotics. "Rescue robotics" is understood here to refer to robot systems designed to relieve the burden on rescue and emergency personnel in dangerous situations or hostile environments. For reliable operation, these rescue robotics systems place high demands on the radio connection between the rescue robotics and the control unit or operator, since a multitude of shielding obstacles can be expected, especially in hostile environments.
[0034] The invention is explained in more detail below using a preferred embodiment with reference to the drawings.
[0035] The drawings show
[0036] Fig. 1 schematically shows a first test scenario for a method according to a preferred embodiment of the invention,
[0037] Fig. 2a, 2b schematically show a second test scenario for a method according to a preferred embodiment of the invention and
[0038] Fig. 3 schematically shows the sequence of a method according to a preferred
[0039] Embodiment of the invention.
[0040] Fig. 1 shows a schematic of an indoor test scenario. The real environment 4 is shown. A three-dimensional structure 5 in the form of a wall is arranged between the mobile robotic system 2 and the control unit 3. Both the mobile robotic system 2 and the control unit 3 have a communication unit 6 with an antenna 7, via which the radio signal 8 can be sent and received, so that a radio connection 1 is established between the mobile robotic system 2 and the control unit 3. The mobile robotic system 2 shown in Fig. 1 is a rescue robot that is partially remotely controlled by an operator 12. The position of the mobile robotic system 2 is determined using a positioning system 11, shown here in the form of a camera.
[0041] The control unit 3 is connected to a planning system 10. Via the planning system
[0042] 10, the operator 12 can model or emulate the virtual environment 4' and model the radio propagation in the virtual environment 4'. If the radio propagation is determined for a test signal 8 'in the virtual environment 4', the real radio signal 8 can be attenuated via the communication unit 6 such that the real radio signal 8 corresponds to the modeled test signal 8'.
[0043] In the scene shown, it is therefore possible to set up an obstacle course with inexpensive Styrofoam or wooden walls as the real environment 4 and subsequently change the material properties in the emulated virtual environment 4', so that radio propagation is modeled for concrete or metal walls. The real radio signal 8, which passes through a wooden wall, is then attenuated in such a way that it behaves exactly like a radio signal that would pass through a concrete wall. It is also possible to assign the radio signal 8 and the test signal 8' to different radio systems. In this way, the influence of emulated radio environments can be investigated in a technology-neutral manner, for example by emulating a real WLAN radio signal with an SG test signal. Radio propagation can therefore be modeled not only for different virtual environments 4', but also for different radio systems.
[0044] Figs. 2a and 2b show an outdoor test scenario. In Fig. 2a, the mobile robotic system 2 is located on a real test site in the real environment 4. The radio connection 1 to the control unit 3 is not disrupted. The position of the mobile robotic system 2 is determined using an external positioning system 11, which is shown in Fig. 2a as a satellite for position determination via a global navigation satellite system. The position of the mobile robotic system 2 is transmitted to the virtual environment 4'. Fig. 2b shows the virtual environment 4' in which additional structures 9 have been added and the existing structure 5' has been emulated. The test signal 8' now passes through one of the added structures 9 in the virtual environment 4', so that the radio connection 1 is not established without attenuation of the test signal 8'. The radio propagation is modeled and the course of the test signal 8' is further tracked in the virtual environment 4'.From this, change parameters for the real radio signal 8 can be derived. These change parameters indicate, for example, a reduced signal strength, so that the real radio signal 8 is attenuated according to the modeled shielding of the test signal 8' in the virtual environment 4'. In this way, the real radio signal 8 can be modeled on an arbitrarily configured and complex virtual environment 4' without having to actually recreate this complex virtual environment 4'. In addition to shielding the test signal 8', reflections on various surfaces or interference with added and modeled interference signals can also be realized. However, this is not shown in Fig. 2a and Fig. 2b. By inserting an interference source into the virtual environment 4', the simulation of a complex real-life scenario can be made even more realistic.
[0045] Fig. 3 shows the flow of a method according to an embodiment of the invention. The first section I comprises step S1, after which the real environment 4 is recreated as a digital twin in a virtual environment 4'. This first section is performed once per test site or environment.
[0046] The second section II comprises steps S2 and S2a. This section II is performed once per test scenario. Step S2 involves modeling the virtual environment 4'. This is done by emulating existing structures 5 and their material properties or by adding additional structures 9 or jammers. Likewise, in step S2a, the radio system under investigation can be emulated if necessary. This means that the real radio signal 8 assumes the behavior and propagation of a test signal 8' of a different radio system.
[0047] The third section III comprises steps S3 to S9. These are continuously repeated so that for each change in position or location of the mobile robotic system 2 within the real environment 4, the radio propagation is always re-determined in real time, thus allowing the behavior of the radio signal 8 to be tested in a dynamic scenario.
[0048] In the third section III, the position of the mobile robotic system 2 within the real environment 4 is first determined S3 and transferred to the virtual environment 4' S4. The radio propagation in the virtual environment 4' is then modeled S5. The test signal 8' is analyzed and signal properties such as latency or packet error rate are determined. After that, change parameters for the real radio signal 8 are determined, which adapt the real radio signal 8 in the real environment 4 according to the modeled test signal 8' in the virtual environment 4' and its signal properties S6, S6a. Finally, the real radio signal 8 is adapted using the change parameters S7 and made available to the communication unit 6 for sending the radio signal 8 to the control unit 3 or from the control unit 3 to the mobile robotic system 2. The aforementioned steps run in real time. The mobile robotic system 2 is then moved so that it can change its position orchanges its location S8. The radio propagation is then remodeled and the real radio signal 8 is adjusted again S9.
[0049] The invention underlying this patent application was developed within the framework of the project "Establishment of the German Rescue Robotics Center (DRZ)" with the funding reference 13N14857 and within the framework of the project "6G Research Hub for Open, Efficient and Secure Mobile Communications Systems - 6GEM", with the funding reference 16KISK038, which were funded by the BMBF.
[0050] List of reference symbols
[0051] 1 radio connection
[0052] 2 mobile robotics system
[0053] 3 Control unit
[0054] 4 real environment
[0055] 4' virtual environment
[0056] 5 structures
[0057] 5' emulated structure
[0058] 6 Communication unit
[0059] 7 Antenna
[0060] 8 radio signal
[0061] 8' test signal
[0062] 9 structures
[0063] 10 Planning system
[0064] 11 Positioning system
[0065] 12 operators
[0066] I first section
[0067] II second section
[0068] III third section
[0069] SI Capturing the real environment and creating a virtual environment
[0070] S2 Modeling the virtual environment
[0071] S2a Emulating the first radio system of the radio link
[0072] S3 Detecting a position of the mobile robotic system in the real environment
[0073] S4 Transferring the position of the mobile robotic system in the real environment to the virtual environment
[0074] S5 Modeling radio propagation of a test signal
[0075] S5a Determining signal properties of the test signal
[0076] S5' Modeling a noise signal and adding the noise signal to the
[0077] test signal
[0078] S6 Determining change parameters for adapting a radio signal
[0079] S6a Adjusting the signal properties of the radio signal Adjusting the radio signal according to the change parameters and transmitting the adjusted radio signal Moving the mobile robot system Repeating steps S3) to S7) in real time
Claims
Patent claims 1. A method for testing a radio connection (1) between a mobile robotic system (2) and an external control unit (3) in a real environment (4), wherein the real environment (4) has at least one three-dimensional structure (5) with predetermined material properties, the mobile robotic system (2) and the external control unit (3) each have a communication unit (6) with at least one antenna (7) for transmitting and / or receiving a radio signal (8), with the following method steps: 51) Capturing the real environment (4) and creating a virtual environment (4'), wherein the virtual environment (4') is a digital twin of the real environment (4), 52) Modelling the virtual environment (4') by means of a planning system (10) by emulating the material properties of the structure (5') of the virtual environment (4') and / or adding further three-dimensional structures (9) with predetermined material properties to the virtual environment (4'), 53) Detecting a position of the mobile robotic system (2) in the real environment (4) by means of an external positioning system (11), 54) Transferring the position of the mobile robotic system (2) in the real environment (4) to the virtual environment (4'), 55) Modelling a radio propagation of a test signal (8') in the modelled virtual environment (4') depending on the position of the mobile robotic system (2) in the virtual environment (4'), 56) Determining change parameters for adapting a radio signal (8) of the radio connection (1) in the real environment (4) according to the modeled test signal (8') in the virtual environment (4') and 57) Adjusting the radio signal (8) according to the change parameters and sending the adjusted radio signal (8) to the mobile robotics system (2) or the external control unit (3).
2. Method according to claim 1, with the following further method steps: 58) Moving the mobile robotic system (2) in the real environment (4), and 59) Repeat steps S3) to S7) in real time.
3. The method according to claim 1 or 2, wherein the modeling of the radio propagation is carried out by means of ray tracing.
4. Method according to one of the preceding claims, wherein the detection of the position of the mobile robotic system (2) in the real environment (4) is carried out by means of GNSS, UWB radio and / or by means of external optical sensors.
5. Method according to one of the preceding claims, wherein at least one communication unit (6) has electronically controllable attenuators for attenuating the radio signal (8).
6. Method according to one of the preceding claims, wherein the radio connection (1) is associated with a first radio system, with the following further method steps: S2a) emulating the first radio system of the radio connection (1) by means of the planning system (3), S5a) determining signal properties of the test signal (8'), wherein the test signal (8') is associated with a second radio system different from the first radio system, and S6a) Adapting the signal properties of the radio signal (8) of the first radio system in the real environment (4) according to the signal properties of the test signal (8') of the second radio system.
7. The method of claim 6, wherein the signal properties include a data rate and / or a packet error rate and / or a latency.
8. The method according to claim 6 or 7, wherein the radio systems can each be selected from the following radio systems: WLAN, LTE, 5G, 6G.
9. Method according to one of the preceding claims, with the following further method step: S5') Modeling a disturbance signal and adding the disturbance signal to the test signal (8').
10. Use of a method according to one of claims 1 to 9 for testing and / or certifying mobile robotic systems (2), in particular autonomous rescue robotics.