Method for controlling an articulated arm with a mobile remote control unit located spatially distant therefrom, and suction excavator

Abstract

The invention relates to a method for controlling an articulated arm with a mobile remote control unit located spatially distant therefrom. To this end, a machine coordinate system is defined which is linked to the articulated arm, and an input coordinate system which is linked to the remote control unit. A deviation between the spatial orientation of the input coordinate system relative to the spatial orientation of the machine coordinate system is then determined. A target movement direction and target movement speed of the end piece of the articulated arm in the input coordinate system are detected via control elements of the remote control unit. The target movement direction is transformed into a transformed movement direction using the determined deviation and the transformed movement direction and the movement speed are transmitted to an articulated arm control unit for controlling at least one drive unit of the articulated arm. The invention also relates to a suction robot which is configured to carry out this method.

Description

[0001]0184 / 23#3-11 RSP October 17, 2023 - 1 - Method for controlling an articulated arm with a mobile remote control unit spatially separated from the articulated arm, and a suction excavator. The invention initially relates to a method for controlling an articulated arm using a mobile remote control unit spatially separated from the articulated arm. Such an articulated arm can be used on various, preferably mobile, work machines, in particular as a component of a suction excavator, namely as an articulated hose carrier. The invention thus also relates to a suction excavator with a remote-controlled articulated hose carrier. A suction excavator is a vehicle with a vehicle frame that carries a preferably tippable material collection container. Multi-link articulated arms are used in many machines to bring an end piece or end effector (e.g., drill head, suction nozzle, or lifting platform) into a specific position and orientation, or to move it along a defined path.Machine-level operation by controlling the pressure in hydraulic cylinders or similar drives to move individual links of the articulated arm is relatively difficult for the user to learn and prone to errors. In addition, specific requirements must be met, e.g., maintaining the end piece in a defined orientation or ensuring optimal distribution of the articulation angles of individual joints. DE 3837 670 A1 discloses a suction excavator comprising a pneumatic suction nozzle, a collecting container for the sucked-up soil, into which the suction nozzle opens and in which the soil is separated from the suction air flow, and a suction fan connected to the collecting container to generate the suction air flow. DE 19851 111 C1 describes a suction excavator with a collection chamber located at the front of the material collection container in the direction of travel and a filter located at the rear in the direction of travel.Two variants have been established for guiding the suction hose of a suction excavator: the telescopic hose carrier and the articulated hose carrier, which is a special type of articulated arm. The telescopic hose carrier only partially guides the hose, so the suction nozzle, which collects the material, must be guided manually by an operator. For several years, the articulated hose carrier (also known as a power arm, guide arm, or articulated boom) has therefore been preferred. It offers the advantage of full hydraulic guidance and good stability. This enables more precise control of the working movements without manual effort and using a preferably mobile remote control unit that the operator can carry. A suction excavator with a remote-controlled articulated boom is known from DE 9016 448 U1.The suction head can be moved into a desired suction position by means of individual control levers using hydraulic pressure cylinders via a remote control unit. JP 2010-228905 A describes a remote control and a method for controlling machines. CN 102 561 700 A describes a machine control technology, namely a mechanical arm control system, as well as a method and a machine therefor. The mechanical arm to be controlled consists of at least two links. The machine comprises a drive unit, a remote control, and a direction adjustment unit. The control method provides for the use of two coordinate systems, one coordinate system being assigned to the remote control and the other coordinate system to the last link of the arm.Using a concrete pump as an example, we further describe how the horizontal rotation between the machine platform of the multi-articulated arm and the remote control can be compensated for by measuring the earth's magnetic field as a common reference direction. As an alternative to the earth's magnetic field, we suggest measuring two reference points. Deviations in the orientation of the two coordinate systems can be offset as long as they can be related to a common reference plane. In practice, however, it has been shown that neglecting a possible vertical tilt of the two coordinate systems relative to each other—i.e., when the two coordinate systems are not in a common reference plane—leads to incorrect inputs, which makes the control system imprecise.DE 102016 106 427 A1 describes a method for controlling the movement of an articulated hose carrier with multiple links, wherein an angular change can be effected between adjacent links using a drive. The starting position of the links is determined using sensors, a direction vector and a speed parameter are input, and a target position is determined that a suction cup at the free end of the last link is to assume. Angle changes that must be made at the links to reach the target position are then determined, such that the suction cup moves along a straight path to the target position. The drives assigned to the links are controlled to effect the previously determined angular change at the links.This is followed by a cyclic repetition of the aforementioned process steps until the direction vector and / or the speed parameter are equal to zero. Although the operation of an articulated arm, in particular an articulated hose carrier, is significantly simplified with the method described in DE 102016 106 427 A1, since the user no longer has to directly control numerous individual drives of the articulated hose carrier, but can, for example, specify a direction vector by deflecting a joystick on the remote control unit, which the control unit then converts into control signals for the individual drives, the difficulty remains that the operator must determine this direction vector themselves in relation to the respective position assumed by the suction nozzle.For example, if the operator is at an angle of 90° to the plane of movement of the articulated hose carrier, he or she must move the joystick perpendicular to the plane in order to move the suction crown in this plane, since the directional vector memorized by the user on the remote control does not take the position or orientation of the mobile remote control unit into account. This requires a great deal of practice and good spatial abstraction skills from the user for correct control. In telematic application scenarios, this challenge can be overcome by allowing the operator to freely select a perspective (e.g., perspective from above), scaling (e.g., thumbnail view for an overview or enlargement for a more detailed view), and restricted visibility (e.g.,The limited aperture angle of a camera) may be further tightened, since the orientation of the reference coordinate systems of the machine control and user inputs can differ considerably and in all dimensions. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 5 - One object of the invention, based on DE 102016 106 427 A1, is to provide an improved method for controlling an articulated arm, in particular an articulated hose carrier, with a mobile remote control unit spatially separated from the latter, with which operation is simplified and thus also possible for largely inexperienced users. Furthermore, the invention is intended to provide a suction excavator for carrying out such a method. This object is achieved by a method according to the appended claim 1 and by a suction excavator according to claim 12.The inventive method for controlling an articulated arm with a mobile remote control unit spatially separated from the articulated arm initially comprises the following steps: A stationary machine coordinate system is defined, which is linked to the articulated arm or the machine unit (suction excavator) supporting it. The machine coordinate system is (quasi) stationary during operation, provided the machine unit is not moved. Typically, however, the machine coordinate system is rotated to any desired extent relative to the input coordinate system of the remote control as well as to generic reference directions such as gravity and the earth's magnetic field. The movement of the articulated arm can be represented, for example, by vectors in the machine coordinate system. In this way, the position of at least one end piece at the free end of the articulated arm can be determined in this machine coordinate system, preferably as the end point of a direction vector.On a suction excavator, for example, a suction nozzle serves as the end piece; on other units, the end piece can be a tool, a grab, a piece of pipe, or a similar element that is to be positioned at a work location for a work task to be performed. In a further step, a dynamic input coordinate system is defined, which is linked to the mobile remote control unit. During operation, there may therefore be situations in which the stationary machine coordinate system of the articulated arm has the same orientation as the dynamic input coordinate system of the remote control unit. However, these two coordinate systems will usually not coincide, resulting in a deviation in one or more coordinates.Once the two coordinate systems have been defined, a deviation between the spatial orientation of the input coordinate system and the machine coordinate system is determined. This deviation can be defined, for example, as a deviation vector or a transformation matrix. The deviation thus also represents the spatial position of the dynamic input coordinate system within the stationary machine coordinate system, which can therefore also be understood as a higher-level coordinate system. Alternatively, a separate higher-level world coordinate system can be defined in which the orientations of the machine coordinate system and the input coordinate system can be determined and related to each other to determine a deviation.To initiate a controlled movement of the end piece of the articulated arm, a target movement direction and target movement speed of the articulated arm, entered by the user via control elements of the remote control unit, are recorded in the dynamic input coordinate system, preferably as a target movement vector. For example, the user operates a joystick on the remote control unit, and sensors on the remote control unit record the speed and direction of the joystick deflection as a target movement vector. In a subsequent step, the target movement vector or the target movement direction is transformed into the stationary machine coordinate system, using the previously determined deviation between the input coordinate system and the machine coordinate system to generate a transformed movement vector or a transformed movement direction in the machine coordinate system.This transformation is preferably performed using a computing unit, which can be part of the remote control unit or the machine unit comprising the articulated arm. The target movement speed only needs to be transformed if the operator's perspective has also been scaled relative to the situation on-site at the machine. This can occur in telematics applications. Finally, the transformed movement vector is transmitted to an articulated arm control unit, which then controls at least one drive unit of the articulated arm to move the end piece to the target position specified by the transformed movement vector. This movement can be initiated by controlling one, several, or all drives on the articulated arm.A particularly preferred control of the articulated arm is described in detail in DE 102016 106 427 A1, cited above, which is expressly incorporated into the disclosure of the invention explained here. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 8 - It is advantageous that the present invention takes into account regularly occurring tilts between the coordinate systems of the machine (machine coordinate system) and the remote control (input coordinate system). Therefore, the three-dimensional rotations of the machine / vehicle and the remote control are fully measured, and preferably also the determination of an independent reference surface, e.g., by evaluating the gravitational vector.Compared to the prior art, this leads to a more robust method in which the respective reference coordinate system is preferably mutually confirmed by at least two measuring methods in order to enable automatic compensation of the rotation between the input and machine coordinate systems. By using a three-dimensional reference coordinate system, the method according to the invention also enables automatic alignment of the end effector and the reduction of incorrect inputs, e.g. when the relationship between the input and machine coordinate systems can no longer be clearly traced due to significant tilting. The articulated arm is preferably an articulated hose carrier, which particularly preferably comprises a plurality of supporting structure elements, preferably five or six links (also referred to as carrier sections), hydraulic cylinders for driving the individual carrier sections, and a mount on the frame of the suction dredger body.Furthermore, a pivot drive is advantageously provided for generating a working radius of the articulated hose carrier. A suction excavator according to the invention is characterized in that it comprises a control unit for controlling the movement of the articulated hose carrier, which is configured to carry out the method according to the invention. Preferably, a material collection container is attached to the suction excavator in such a way that it can be tipped out. Preferably, the suction excavator that carries out the described method for controlling the movement of the articulated hose carrier has a sensor on each link of the articulated hose carrier, which sensor is directly or indirectly suitable for determining the angle that arises when two adjacent links move around the joint located between them under the action of an associated drive.The drives are controlled by the control electronics in such a way that adjustment angles are created which, within the framework of so-called inverse kinematics, allow the last link (end piece) or the suction crown or the suction nozzle to be moved freely at least in an XY plane, but preferably in a 3D coordinate system. A specification via the control system for changing the position of the suction crown, which represents the end piece, is made in the dynamic input coordinate system of the remote control unit and with subsequent transformation into the stationary machine coordinate system of the articulated hose carrier or the suction excavator. In this way, the suction crown or the end piece of the articulated hose carrier can be moved to the specified position in a targeted and direct manner using just one control element (e.g. a joystick) and a control input on this by the operator.The method according to the invention advantageously allows the control of the position of an end piece on a movable articulated arm with any number of links, each with one-dimensional rotation about the joints of the articulated arm, by the direct input of the direction of movement and the speed of movement, preferably as a movement vector ^. ^^^ ^ im © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 10 - dynamic input coordinate system M Ia mobile remote control unit. The method described here allows the automation of complex operating processes based on movement inputs in the dynamic input coordinate system of the remote control unit, thereby simplifying the operating processes for the user. The inputs for the desired movement of the end piece are interpreted in the dynamic input coordinate system of the remote control unit and are therefore independent of the relative orientation between the machine and the remote control unit, or of the position and orientation of the user. In an advantageous embodiment, the input coordinate system of the remote control unit is defined by determining a gravitational vector ^, whereby the detected desired direction of movement is corrected in order to compensate for any deviation between the position of the vertical axis of the remote control unit and the gravitational axis.Knowledge of the gravitational vector, preferably in both coordinate systems, is relevant for executing inputs that are desired to be planar on a horizontal plane in the input coordinate system, correspondingly planar, i.e., orthogonal to the gravitational vector, on the machine or articulated arm, even if the input coordinate system (i.e., the remote control unit) is tilted relative to the horizontal. This is intended to prevent the end piece from being moved diagonally up or down by a horizontal input vector simply because the remote control unit is tilted at the moment of the input. Inputs are preferably only applied when the remote control is tilted by less than 45 degrees, so that the inputs are interpretable and only the deviating rotation around the gravitational axis is taken into account. The Earth's magnetic field, for example, can be used as a reference.The definition of the input vector on the remote control unit is therefore preferably carried out taking the gravitational vector into account in order to determine a desired direction of movement of the end piece independent of the inclination of the remote control unit relative to the gravitational vector, while the rotation of the remote control unit around the gravitational axis (also known in aviation as the yaw angle) influences the desired direction of movement. However, the measurement of the earth's magnetic field and gravity can be unreliable or even impossible, for example in construction site situations. The earth's magnetic field is easily overlaid by local magnetic fields (e.g. from electric motors), and the measurement of gravity is disturbed by local shocks and vibrations. In a modified preferred embodiment, a local reference coordinate system with at least three reference points is therefore used. This reference coordinate system can preferably be integrated into construction site furniture, such as construction fences or the like.According to a further embodiment, a computational leveling of the rotation in the joint of the end piece is also possible in order to automatically maintain its inclination angle relative to the gravitational vector or another reference angle. According to an advantageous embodiment, the above-mentioned method steps are specified, supplemented, and executed as follows: - The target movement direction and target movement speed (target movement vector ^) are set on the remote control unit. ^^^ ^ ) in the dynamic input coordinate system M R recorded; © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 12 - - the thus defined target motion vector V I is converted into the stationary machine coordinate system M M of the articulated arm; - in the stationary machine coordinate system M Ma new target position of the end piece is calculated through a given time window of the movement; - spherical coordinates (ϕ, ϑ, r) of this target position are calculated; - based on current values, a binary search for a reference angle α is carried out R to achieve the length r at predefined ratios of the joint angles to α n executed; - Adjustment of the first joint angle α0 to achieve the correct polar angle ϑ; - Adjustment of the angle to the end piece α E to ensure a constant orientation in the Cartesian stationary machine coordinate system M Mof the articulated arm or the machine unit carrying it; - checking all target angles for mechanical accessibility (valid value ranges); - if a target angle is not valid, stop or recalculate by repeating a binary search with adjusted angle ratios; - if all target angles are valid, simultaneous adjustment of all joint angles by opening the hydraulic valves of the articulated arm in proportion to the remaining deviation from the target angle (and if necessary taking the existing pressure into account) in a control loop until all target angles have been reached. It was shown above that it is essential for carrying out the method according to the invention that a deviation between the stationary machine coordinate system © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 13 - of the articulated arm (the machine unit) and the dynamic input coordinate system of the remote control unit and is applied in the transformation of the desired motion vector. The accuracy of the control thus depends on the precise determination of the orientation of the two coordinate systems. This can lead to problems, particularly under the harsh conditions of a construction site. Preferred embodiments of the invention are therefore presented below that address and solve this partial problem, in particular the precise measurement of the position and orientation of the remote control unit, the end piece, and the position or angle assumed by the individual joints of the articulated arm. Various known 3D measuring systems can generally be used to acquire the measured values ​​in order to acquire the required data at high frequency.However, when using construction machinery on construction sites, additional restrictions must be taken into account, for example: - ultrasound-based systems operate unreliably if there is too much background noise and variable sound reflectors; - electromagnetic systems are disturbed by the metal housings and electric motors of construction machinery; - radio-based systems and radar are inaccurate and are disturbed by high local dynamics; - optical systems are easily outshone by sunlight (including infrared); passively illuminated markers are more robust in this case; - optical systems generally suffer from dust and visual obscuration by moving components, tools and machines; in the dark they require artificial lighting; © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 14 - - Mechanical measuring systems are generally susceptible to failures in moving parts, but particularly in environments with strong environmental influences; - Inertial sensors are disturbed by vibrations of the machine units when measuring accelerations (e.g., when detecting the gravitational vector), and the measurement of the earth's magnetic field can be disturbed by local electromagnetic fields, e.g., from electric motors. To overcome the aforementioned difficulties and limitations, various solutions are presented below that can be used individually or in combination within the scope of the invention. They thus represent preferred embodiments that can be used in particular on a suction dredger according to the invention.To detect the orientation of the input coordinate system relative to the orientation of the machine coordinate system, various measuring systems are preferably used, in particular optical measuring systems with which passively or actively illuminated markers can be detected; and inertial sensors with which the gravitational vector and the Earth's magnetic field can be determined. The relative orientation can also be manually adjusted by the operator. To define the input coordinate system, the relative rotation around the gravitational axis of the input coordinate system and the machine coordinate system is preferably derived from a position measurement of at least two points. For this purpose, optical systems based on passively illuminated markers in the spectrum of visible light or laser-based position measuring systems are preferably used.Such systems are known as "lighthouse"; they are laser-based inside-out position tracking systems. Such systems are described, for example, in US 10338 186 B2. Although they use active light (usually infrared), in a pulsed laser this can be bright enough to stand out from sunlight as a signal. However, high-energy lasers also pose the risk of blinding bystanders. The combination of passively illuminated markers and high-resolution cameras in the visible light spectrum is a particularly preferred option for reasons of occupational safety and cost. In addition, a camera can be mounted on the machine unit (e.g., suction excavator) that carries the articulated arm, on a tripod, on construction site furniture (e.g., fences), and / or on the remote control unit. However, a single camera does not provide depth information.Therefore, high-performance stereo cameras can preferably be installed on a tripod and / or on the vehicle. A camera can be attached to the remote control unit, in particular, with little effort and is easy to clean. Robust acquisition of 3D information can be achieved through movement while the recorded elements (machine unit, articulated arm links, and end piece) remain stationary. The use of optical 3D measuring systems is therefore particularly suitable for relatively infrequent comparative measurements for the calibration of other measurements. A mechanical measuring system is ideal because the articulated arm already provides the basic mechanical structure and is also robust enough for harsh construction site use. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 16 - The angles between individual articulated links can be measured both mechanically and using inertial sensors.The latter, however, can be disrupted by vibrations in the machine unit. These disturbances can be corrected using appropriate low-pass filters, but this also results in a reduction in the achievable recording frequency and thus impairs the control loop for reducing angular errors for the target position of the end piece. When using inertial sensors, the inclination of the entire machine unit must also be taken into account in order to derive the correct articulation angles of the articulated arm links from the measured gravitational vectors. A preferred embodiment uses mechanical rotary encoders. A modified embodiment uses hydraulic cylinders with linear position sensors on the articulated arm to determine the position of the individual joints. By taking the mechanical geometry into account, the resulting articulation angles between articulated arm links can also be derived from the deflection of the hydraulic system.Potential errors from high-frequency mechanical measurements can be detected and corrected by low-frequency measurements from the inertial sensors. Therefore, high- and low-frequency measurements are preferably combined. Preferably, optical measurements on passively illuminated markers are also included (at an even lower frequency) using a camera, preferably in the remote control unit, particularly for regular calibration of the overall system. In particularly sensitive or critical moments, continuous optical tracking of the end piece can also be performed. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 17 - In a modified embodiment, one or more cameras in the remote control unit can measure the relative orientation of the remote control unit to the end piece of the articulated arm and / or to the vehicle (suction excavator).The remote control unit, like the entire machine and the end piece, can preferably be equipped with a 3D inertial sensor (IMU). Measurement of the earth's magnetic field is also relevant for the correct interpretation of the movement inputs. To quickly detect disturbances and resulting errors, the values ​​of several IMUs can be compared at positions that are as far apart as possible but mechanically firmly coupled. Preferably, the proposed automatic transformations from the input to the machine coordinate system are only applied if the measurement of a common reference coordinate system is confirmed by at least two independent measuring systems. Further details, advantages, and developments of the present invention will become apparent from the following description of preferred embodiments with reference to the drawings. They show: Fig.1 shows a symbolic representation of a suction excavator being operated on a construction site by a user using a remote control unit; Fig. 2 shows a symbolic first representation of an articulated arm and a remote control unit for carrying out a method according to the invention for controlling the articulated arm; © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 18 - Fig. 3 shows a symbolic second representation of the articulated arm to illustrate the position of an end piece relative to a root joint; Fig. 4 shows a graph representation of possible relations between a dynamic input coordinate system of the remote control unit and a stationary machine coordinate system of the articulated arm with the position of the end piece; Fig. 5 shows a flow chart of a process chain for calculating all angles of the articulated arm from a target movement vector in the dynamic input coordinate system;Fig. 6 shows a symbolic third representation of the articulated arm to illustrate the division of angles between the links of the articulated arm; Fig. 7 shows an illustration of the chaining of vectors for calculating a point and its distance from the root joint. Fig. 1 illustrates a typical application situation in which a suction excavator 10 with an articulated arm 01 is used on a construction site. A stationary machine coordinate system M. M of the suction dredger 10, an end effector coordinate system M E an end effector 04 and a dynamic input coordinate system M I a remote control unit 02 are three-dimensionally rotated relative to each other and also deviate from a world coordinate system M based on gravitational vector and earth's magnetic field WAn alternative reference coordinate system can be realized by measuring three reference points P1, P2, P3, which are attached, for example, to construction site furniture such as construction fences. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 19 - Fig. 2 shows a schematic diagram of the articulated arm 01, which, in the exemplary embodiment considered below, is an articulated hose carrier of a suction excavator (Fig. 1). The articulated arm 01 has several articulated arm links L n , each connected via joints J nare connected to one another. The remote control unit 02 is provided spatially separate from the articulated arm 01 and can be used by a user 03 to control the desired movements of the articulated arm 01. In telematic applications, this can also be located out of sight and within direct reach, i.e., any distance away. The remote control unit 02 and an articulated arm controller (not shown) interact to carry out the inventive method for controlling the articulated arm. The ultimate goal is to move the end effector 04 (also called the end piece), which is located at the free end of the articulated arm 01, to a desired target position in order to perform a work task there. In the case of a suction excavator, this work task usually consists of picking up material, e.g. excavated soil, using the negative pressure generated by a fan unit of the suction excavator, and transporting the material through a suction hose carried by the articulated arm into a material collection container.In Figures 1, 2, 3, 6, and 7, coordinate system symbols are shown for ease of understanding. Coordinate system symbols without arrowheads represent only an orientation and not a relevant position. The articulated arm links L. n rotate around the joints J n . The orientation of the articulated arm 01 is determined in the stationary machine coordinate system M M depicted, while the © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 20 - orientation of the remote control unit 02 in the dynamic input coordinate system M I Fig. 3 also shows the basic structure of the articulated arm 01 according to Fig. 2. The angle ranges shown here serve primarily to illustrate the position of the end piece 04. The end piece 04 is at the last joint J E attached and can also be understood as an end effector, whose position P E at the last joint J E The movement of position PE The end effector's position is shown in Fig. 3 relative to the root joint J0 or to the first joint J1, which on the suction dredger is only rotatable about the Z-axis relative to the root joint J0 (no angular change between J0 and J1), in spherical coordinates (ϕ, ϑ, r). The following explanations for the implementation of the method also refer to this type of representation. The following assumptions are made for the functional implementation of the method for controlling the articulated arm in the embodiment of the articulated hose carrier of a suction dredger: a) The articulated arm 01 consists exclusively of one-dimensional rotational joints J n , where all joints J1 to J i are identically oriented and only at the root joint J0 or J1 an additional rotation with a rotation axis rotated by 90° is possible. b) The movement of the end effector P E relative to the root joint J0or J1can be expressed in spherical coordinates (ϕ, r), where the azimuth angle ϕ is determined exclusively by the angle of the root joint J0 at the arm's suspension and the angles α n all other joints J1 to J i jointly determine the length (or the spherical radius r) and the polar angle ϑ (see Fig. 3). c) The ratios of the individual joint angles α2 to α i are predefined by weights ^ and offsets ^ (e.g. uniformly distributed), so that the radius r, ie the distance of the end effector position P E to the root joint J1by specifying a single reference angle ^ can be determined: ^ ^ = ^ ^ ∗ ^ + ^ ^ where in the following a uniform distribution of the angles α2 to α5 is assumed, ie: ^ ^ = 1 and ^ ^ = 0. d) The orientation of the input coordinate system M I the remote control unit and the machine coordinate system M Mare defined together in a higher-level coordinate system (here, the world coordinate system MW) (see Fig. 4a). Alternatively, M I in M M (Fig. 4b) or M M in M I (Fig. 4c). In addition, the position of the end effector P E in the machine coordinate system M M be defined. The following descriptions are based on a spatial structure (Fig. 4a). M W does not need to indicate an origin position; a reference frame for orientation is sufficient, e.g., based on gravity and the north pole of the Earth's magnetic field (see Fig. 2 or Fig. 3). Alternatively, a reference coordinate system can be determined by measuring at least three reference points (see P1-P3 in Fig. 1). © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 22 - Fig. 4 shows possible relations between the input coordinate system M I and the machine coordinate system M M with the position of the end effector PE as a graph. As already explained above, the control of at least one drive unit of the articulated arm 01 to move the end piece 04 or end effector P Eto a target position specified by the transformed motion sector using a previously known control system, as described, for example, in DE 102016 106 427 A1. Such a control system can also be referred to as inverse kinematics, since it always controls the individual joints depending on the target position of the end piece. A possible technical implementation of this inverse kinematics on an articulated hose carrier of a suction excavator can be carried out as follows: 1. The control commands from the remote control unit are first processed algorithmically to indirectly manipulate the oil pressure in the hydraulic cylinders for moving the articulated arm links, resulting in controlled movements of the end effector. 2. The articulated arm consists exclusively of one-dimensional rotation joints, with all joints oriented identically and only the root joint J0 having a rotation axis rotated by 90°. 3.The movement of the articulated arm can be defined in spherical coordinates, where the azimuth angle. is determined exclusively by the angle of the root joint J0 at the arm's suspension and the angles of all other joints © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 23 - J njointly determine the length (or the sphere radius r) and the polar angle ϑ. 4. The ratios of individual joint angles are predefined (e.g. evenly distributed) so that the desired arm length r can be determined by specifying a single angle value. 5. The angles of the articulated arm links are recorded simultaneously using different sensors and measuring methods in order to eliminate the respective systematic measurement errors. These are preferably two or more of the following sensors: a. rotary encoders in the joints of the multi-link articulated arm; b. linear position sensors in the hydraulic cylinders; c. inertial sensors for measuring the gravitational vector; d. camera-based or laser-based sensors for the absolute measurement of the position and orientation of the individual articulated arm links, including the end effector, relative to an external measuring station, e.g.: i. on the machine, ii. mobile on a tripod or integrated into construction site furniture such as fences, iii.Mobile on the remote control unit. 6. The relative orientation of the articulated arm and the remote control unit is recorded by a combination of sensors to eliminate systematic measurement errors. These are preferably: a. 3D inertial sensors in or on the remote control unit and on the articulated arm; © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 24 - b. Redundant 3D inertial sensors with the greatest possible spacing and a fixed mechanical connection to detect and evaluate disruptive effects of local magnetic fields on the electronic compasses. c. Camera-based or laser-based sensors for the absolute measurement of the orientation of the remote control unit, articulated arm, and end effector relative to each other or relative to an external measuring station, e.g.: i. on the machine, ii. mobile on a tripod or integrated into construction site furniture such as fences, iii. mobile on the remote control unit. 7.The position of the end effector is recorded simultaneously using two measuring methods to detect systematic measurement errors. These are preferably: a. mechanical measurement of the end effector based on the orientation of all links of the articulated arm; b. camera-based or laser-based sensors for the absolute measurement of the orientation of the remote control unit, articulated arm, and end effector to one another or relative to an external measuring station, e.g.: i. on the machine, ii. mobile on a tripod or integrated into construction site furniture such as fences, iii. mobile on the remote control unit. Fig. 5 shows a flowchart of the process chain for calculating all angles ^. ^ of the articulated arm 01 from a target movement vector recorded on the remote control unit 02 ^ ^^^ ^ im Input coordinate system ^ ^ . The control commands of the remote control unit 02 are processed in the sequence shown in Fig. 5 to determine all target angles α n of the joints J nto determine, © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 25 - so that a controlled movement of the end effector P E along a transformed motion vector ^ ^^^ ^ ^^ ^ ^^^ ^ ^ This results in the transformation of the target motion vector ^ ^^^ ^ in den transformed motion vector using the previously determined deviation between the input coordinate system M I and the machine coordinate system M M One possibility of this transformation is described below for the case of mapping M M and M I in a common reference coordinate system M W (see Fig. 4a) explained in detail: I. Leveling (optional): The target motion vector ^ ^^^ ^ ist im Input coordinate system M I the remote control unit. Before the transmission (transformation) of ^ ^^^ ^into the machine coordinate system M M the input coordinate system M I aligned or leveled according to the previously determined gravitational vector ^, so that only the rotation of the remote control unit 02 around the gravitational axis needs to be taken into account. For this purpose, a new leveled input coordinate system M is created in the following sub-steps. I-U constructed: 1. First, it is checked whether the input coordinate system M I is inclined to the gravitational vector ^ less than 90°, ie the scalar product of a unit vector along the z-axis of the input coordinate system ^ ^ = (0, 0, 1) with the inverse of the normalized gravitational vector ^ ^ = (^) ⁄ ‖^‖ in a common world coordinate system ^ ^ is less than zero, so both point in different directions: ^ ^ ∗ ( ^^ ∗ ^^ ) < 0 (assuming that ^ is already in the world coordinate system ^^ is defined) © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 26 - Otherwise, the remote control unit is tilted downwards and no unambiguous interpretation of the input vector is possible. In this case, control of the articulated arm should be interrupted. 2. If the precondition ^ ^ ∗ (^ ^ ∗ ^ ^ ) < 0 is satisfied, the axes of the leveled input coordinate system M I-U by calculating cross products between the x- or y-axis of the input coordinate system and the gravitational vector (in the common world coordinate system ^ ^ ) is constructed (here using the y-axis as an example, i.e. a unit vector along the y-axis ^ ^ ). ^ ^^^ = ^ ^^^ × ^ ^^^ ^ ^^^ = ^^ ^^ 3. To get the desired motion vector ^ ^^^ ^ to be leveled accordingly, it is simply set to identical values ​​in the leveled input coordinate system M I-Uexpressed. II. Input transformation: The input vector ^ ^ or the leveled input vector can now be expressed by the following calculation rule in the machine coordinate system: III. New target position: If the current position of the end effector is set as point ^ ^ in the machine coordinate system ^ ^ known, the new target position ^ ^ ^ by shifting along the transformed motion vector in the machine coordinate system. © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 27 - ^ ^ ^ = ^ ^ + ^ ^^^ ^ ^^ ^ ^^^ ^ ^ IV. Spherical coordinates: The target position of the end effector must be converted into spherical coordinates to ^ ^ ^ = t ^ ^^ ^ + ^ ^The orientation of the machine coordinate system must be taken into account and the resulting angle values ​​must be shifted by a multiple of ^⁄ 2 if necessary. Alternatively, all three values ​​of the spherical coordinates can also be determined by vector calculations. The radius r, or the distance to the target position ^′ ^ from the root joint the length of the vector between both points. The swivel angle ^ ^ = φ is the scalar product of a unit vector along a reference axis in the machine coordinate system ^ ^ (e.g. the x-axis in Figs. 2 and 3) and the normalized projection of ^ ^^ ^ ^^^ ^ ^^^ ′ ^^ ^ to the horizontal plane of the machine coordinate system ^ ^ (e.g. the x / y plane in Figs. 2 and 3). To project ^ ^^ ^ ^^^ ^ ^^^ ′ ^^^ to the desired plane, the vector component of the dimension to be ignored (e.g., z) can be set to zero. The projection can be written using cross products, e.g.: © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 28 - ^is the dot product of a unit vector along a reference axis in the machine coordinate system ^ ^ (e.g. the z-axis ^ ^ in Figs. 2 and 3) and the normalized vector ^ ^ ^′ ^ in the machine coordinate system ^ ^ . The swivel angle is already given as a result of this process step: ^ ^ = φ If ^ ^ = ^ ^ , the vector ^ ^^ ^ ^^^ ^ ^^ ^ the angle ^^into the components ^ ^^ and ^ ^^ and ^ ^ in ^ ^^ and ^ ^^ (see Fig. 6) where: V. 2D Inverse Kinematics: Calculating the angles ^ ^ to ^ ^can be solved in a two-dimensional coordinate system, since all joints ^ ^ to ^ ^ lie on the same plane and rotate around parallel axes. The sizes of the angles ^ ^ until define together with the lengths of the adjacent links ^ ^ to ^ ^ the length of the vector ^^ ^^ ^ ^^^ ^ ^^ ^ ^. We are looking for the angles^ ^ to ^ ^ with which applies: An analytical solution exists only in special cases. As a generic solution for a virtually arbitrary number of terms, varying ratios of the angles ^ ^ until as well as different lengths of the adjacent links ^ ^ to ^ ^ the following possible solution is described: © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 29 - 1. The geometric relationships of the length-relevant terms ^ ^ to ^ ^are expressed in isolation in an independent 2D coordinate system, where L1 is aligned to the x-axis (since ^ ^ no influence on the vector length ^ ^ ^^ ^ ^^^ ^ ^^ ^ ^hat; see Fig. 6 and 7).2. Each of the length-relevant members ^ ^ to ^ ^ is now expressed as a 2D vector in this coordinate system and accordingly the angle ^ ^ with ^ ^ = ^ ^ − ^ rotates (see Fig. 7). For ^ ^ applies ^ ^ = 0, since ^ ^ aligned along the x-axis. The coordinates of the vectors bis are calculated as follows (with ^ ^ to ^ ^ as lengths of the links ^ ^ to ^ ^ ): ^ ^^ = ^ cos(^ ^ ) ^ ^^ = ^ sin( ^^ ) ^ ^^ = ^ cos ( ^^ + ^^ ) ^ ^^ = ^ sin(^ ^ + ^ ^) … … 3. From the concatenation of the resulting 2D vectors ^ ^ ^^^ ^ bis ^ ^ ^^ ^ results in a point ^ ^ (see Fig. 7). ^ ^ = ^ ^ ^^^ ^ + ^ ^^^^ ^ + ⋯ + ^ ^ ^^ ^ 4. Now it is time to find the right values ​​^ ^ to find where the distance ^ ^ ^ ^ ^ ^^^ ^ ^^^ ^ ^the target distance corresponds to. AllValues ​​^ ^ are defined by a common reference angle ^ © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 30 - since ^ ^ = ^ ^ − ^ and ^ ^ only by predefined weights ^ ^ and offsets ^ ^ deviate from ^. ^ ^ = ^ ^ ∗ ^ + ^ ^ A binary search algorithm is used to find the matching ^. In addition to the global parameter limits ^ ^^^ and ^ ^^^There are also local limitations here ^ ^^^^^ and ^ ^^^^^ to be taken into account. If necessary, local weights allow ^ ^ and offsets ^ ^ an optimization of the range of motion of the entire articulated arm. 5. From the found value of ^, taking into account the local weights ^ ^ and offsets ^ ^ all angle values ​​of ^ ^ until derive. ^ ^ consists of ^ ^^ , which was already found in step IV. during the translation into spherical coordinates, and ^ ^^ . The latter is the angle, i.e. the scalar product between the normalized vector ^ ^ ^ ^ ^ and a unit vector along the x-axis of the auxiliary coordinate system used here: ^ ^^ = ^ ^ ^ ^ ^ ∗ ^ VI. End piece alignment: For the calculation of the last remaining angle ^ ^ , is after determining ^ ^^^ ^^^ ^ ^^^ ^ und the individual vectors bis already a part calculable: ^ ^^ = ^ ^ ^ ^ ^ ∗ ^^^^ ^ ^^ can be calculated as the scalar product of ^ ^ ^ ^ ^ and a vector in the target orientation of the last link ^ ^ ^^^ ^ Since the latter is defined relative to a vector in the reference coordinate system, e.g., the gravitational vector ^, we use its normalized representation in the machine coordinate system ^ ^ for reference: Desired deviations of the orientation of ^ ^ ^^^ ^ vom Gravitational vector ^ can then be directly compared with the determined angle ^ ^ Fig. 6 shows the division of ^1in ^ 1^ and ^ 1^ as well as from ^ ^ in ^ ^^ and ^^^ by the vector ^ ^ ^^ 1 ^^^^^ ^ .The length of the vector^ ^ ^^ ^ ^^^ ^ ^^ ^ ^ is determined by the lengths of the links ^ ^ , ^ ^ , ^ ^ and the included angles ^ ^ and ^ ^ Fig. 7 shows the concatenation of the vectors bis ^ ^^^ ^ to calculate a point ^ ^ and its distance from the root joint © PATENTSCHUTZengel 0184 / 23#3-11 RSP 17.10.2023 - 32 - Reference numerals 01 – Articulated arm / Articulated hose carrier 02 – Remote control unit 03 – User 04 – End piece / End effector L n – Articulated arm links J n – Joints P E – Position of the end effector P1, P2, P3- Reference points M I - Input coordinate system M M – Machine coordinate system M E – End effector coordinate system M W – World coordinate system ^ ^ ^^^ ^^ ^ ^^^ ^ ^ – transformed motion vector^ ^^^ ^ - Target motion vector © PATENT PROTECTION angel

Claims

0184 / 23#1-11 RSP 17.10.2023 - 33 - Patent claims 1. Method for controlling an articulated arm (01) with a mobile remote control unit (02) spatially remote from the latter, comprising the following steps: - definition of a machine coordinate system (M W ), which is connected to the articulated arm, so that the position of at least one end piece (04) at the free end of the articulated arm can be determined in this machine coordinate system; - definition of an input coordinate system (M I), which is linked to the remote control unit (02); - Determination of a three-dimensional deviation between the 3D spatial orientation of the input coordinate system compared to the 3D spatial orientation of the machine coordinate system; - Detection of a desired movement direction and desired movement speed of the end piece (04) of the articulated arm in the input coordinate system, entered via operating elements of the remote control unit (02); - Transformation of the desired movement direction into a transformed movement direction using the determined 3D deviation between the input coordinate system (M I ) and the machine coordinate system (M M); - transmission of the transformed direction of movement and the speed of movement to an articulated arm control unit and control of at least one drive unit of the articulated arm to move the end piece (04) to the predetermined target position.

2. Method according to claim 1, characterized in that the definition of the input coordinate system of the remote control unit takes place by determining a reference plane, wherein © PATENT PROTECTION angel 0184 / 23#1-11 RSP 17.10.2023 - 34 - the detected target direction of movement is corrected to compensate for a deviation between the position of the vertical axis of the remote control unit and the reference axis located on the reference plane.

3. Method according to claim 2, characterized in that the determination of the reference plane is based on a gravitational vector, wherein the detected target direction of movement is corrected to compensate for a deviation between the position of the vertical axis of the remote control unit and the gravitational axis. 4.Method according to one of claims 1 to 3, characterized in that the desired movement direction and the desired movement speed of the end piece are detected as a desired movement vector in the input coordinate system; and that the desired movement vector is transformed into a transformed movement vector using the determined deviation between the input coordinate system and the machine coordinate system; and that the transformed movement vector is transmitted to the articulated arm control unit.

5. Method according to claim 4, characterized in that spherical coordinates of the target position are calculated based on the transformed movement vector in the machine coordinate system. 6.Method according to one of claims 1 to 5, characterized in that the transformation from the input coordinate system into the machine coordinate system is carried out taking into account the determined three-dimensional deviation only when the three-dimensional © PATENT PROTECTION angel. 0184 / 23#1-11 RSP 17.10.2023 - 35 - The spatial deviation between the 3D spatial orientation of the input coordinate system and the 3D spatial orientation of the machine coordinate system is confirmed by measurements with at least two independent measuring systems.

7. The method according to one of claims 1 to 6, characterized in that, to define the input coordinate system, its orientation relative to the machine coordinate system is measured, preferably using one or more measuring systems from the following list: - optical measuring systems with which passively or actively illuminated markers can be detected; - inertial sensors with which the gravitational vector and the Earth's magnetic field can be determined. 8.Method according to one of claims 1 to 6, characterized in that , to define the input coordinate system, the relative rotation about the gravitational axis of the input coordinate system and the machine coordinate system is derived from a position measurement of at least three points, preferably using one or more measuring systems from the following list: - laser-based position measuring systems, preferably with pulsed light; - optical measuring systems with which passively or actively illuminated markers can be detected; - stereo cameras, which are preferably arranged on the machine unit carrying the articulated arm or on stationary construction site furniture; - one or more cameras, which are arranged on the remote control unit or on stationary construction site furniture. © PATENT PROTECTION Engel. 0184 / 23#1-11 RSP 17.10.2023 - 36 - 9. The method according to one of claims 1 to 8, characterized in that position measurements are carried out to determine the position of the end piece, preferably using one or more measuring systems from the following list: - optical measuring systems with which passively or actively illuminated markers can be detected; - laser-based position measuring systems, preferably with pulsed light; - stereo cameras, which are preferably arranged on the machine unit carrying the articulated arm; - one or more cameras arranged on the remote control unit; - a mechanical measuring system on the articulated arm, preferably with rotary encoders; - inertial sensors on the joints of the articulated arm and / or on the remote control unit.

10. The method according to one of claims 1 to 9, characterized in that the earth's magnetic field is measured and taken into account to define the input coordinate system and the machine coordinate system. 11.Method according to one of claims 1 to 10, characterized in that the articulated arm is a component of one of the following devices: ^ suction excavator; ^ concrete pump; ^ sewer cleaning machine; ^ sewer inspection machine; ^ drilling machine; ^ lifting platform. © PATENT PROTECTION Engel. 0184 / 23#1-11 RSP 17.10.2023 - 37 - 12. Suction excavator with a vehicle frame, a fan unit for generating a suction flow for collecting material, a filter unit, a material collection container for collecting the collected material, a multi-section articulated hose carrier, and a mobile remote control unit for controlling the movement of the articulated hose carrier, characterized in that a control unit of the suction excavator and the remote control unit are configured to carry out a method according to one of claims 1 to 11. © PATENT PROTECTION Engel

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