Floating platform for a robot manipulator

Abstract

Platform (1) with a robot manipulator (3) arranged on the platform (1) and with a suspension device (5), wherein the suspension device (5) is configured to support the platform (1) on a support body (20) by forming a suspension such that, under the influence of gravity, the suspension allows a pendulum movement of the platform (1) relative to the support body (20), and wherein the platform (1) comprises: - a control unit (10), - a sensor unit (11) configured to detect motion data of the platform (1) and to transmit the motion data to the control unit (10), and - an actuator unit (12) configured to exert a force and / or a moment on the platform (1) and which can be controlled by the control unit (10), wherein the control unit (10) is configured toto control the robot manipulator (3) and to control the actuator unit (12) on the basis of the motion data acquired by the sensor unit (11) to exert a force and / or a torque in the opposite direction to an unwanted movement of the platform (1).

Description

The invention relates to a platform having a robot manipulator arranged on the platform and having a suspension device for suspending the platform on a supporting body, and to a flight unit having a rotorcraft as supporting body and having the same platform, and to a method for controlling or regulating faults on a platform having a robot manipulator arranged on the platform and having a suspension device.Platforms suspended from a helicopter are known in the prior art. Thus, U.S. Pat. No. 3,838,836 A relates to a method for load stabilization for use on a heavy load helicopter. Furthermore, aircraft are known in the prior art, which can be controlled in particular by a propeller drive. DE 10 2006 057 808 A1 relates to a flight transporter with rigid cell structures for this purpose. Furthermore, DE 10 2005 006 936 A1 relates to a cable control head for the targeted horizontal deflection of freely suspended cable ends, wherein a housing with a built-in or built-on remotely controllable push and control unit is suspended in the cable. DE 103 33 724 A1 relates to a movement generation by means of a mass by drive for generating an omnidirectional movement of a running ball, which comprises a spherical running shell and the mass arranged in a positionally displaceable manner in the interior of the running shell, wherein the mass is connected to the running shell at a plurality of length-variable push / pull elements distributed equidistantly around the periphery of the mass. US 5 816 098 A further relates to orientation control of a load by means of the gyro effect. Furthermore, JP 2005271831 A relates to an unmanned flying object with gas as buoyancy means.The object of the invention is to enable precise robot manipulation in space.The invention results from the features of the independent claims. Advantageous refinements and refinements are the subject matter of the dependent claims.A first aspect of the invention relates to a platform having a robot manipulator arranged on the platform and having a suspension device, wherein the suspension device is designed to mount the platform on a supporting body by forming a suspension such that, under the influence of gravity, the suspension allows a pendulum movement of the platform with respect to the supporting body, and wherein the platform has:a control unit,a sensor unit which is designed for detecting movement data of the platform and for transmitting the movement data to the control unit, andan actuator unit which is designed to exert a force and / or a moment on the platform and can be controlled by the control unit, wherein the control unit is designed to control the robot manipulator and to control the actuator unit on the basis of the movement data recorded by the sensor unit to exert a force and / or a moment opposite to an undesired movement of the platform.The suspension device preferably has one or more cable strands, in particular cable strands made of polyamide fibers or fibers made of ultra-high molecular weight polyethylene or made of polyester or made of a steel alloy, alternatively made of another preferred plastic or metallic wire mesh. Alternatively preferably, the suspension device has one or more rods articulated on both sides, preferably made of glass fiber-reinforced or carbon fiber-reinforced plastic or made of a metallic material. Alternatively preferably, the suspension device has one or more chains. Alternatively preferably, the suspension device has one or more lines. In the case of a preferred embodiment of the supporting body as a missile, a moment dynamics of the platform, i.e. an angular acceleration of the platform with the robot manipulator corresponding to an external moment or an external force, is thus decoupled from a moment dynamics of the missile, in particular when the suspension device is merely suspended on the supporting body at exactly one rotatable support point. A further effect of this suspension is a frequency-dependent force and / or position transmission from the supporting body to the platform, wherein this transmission function has, in particular, low-pass characteristics. In particular, periodic force and deflection excitations, i.e. vibrations, are transmitted by the supporting body as a source to the platform, starting from low frequencies, only up to a specific bandwidth and, above this bandwidth, have an effect on the platform with an increasing amplitude loss and phase distortion over the excitation frequency.The actuator unit preferably comprises at least one of: propeller, rotor, flywheel, translatory displaceable compensating mass, gas-operated thrust nozzle, in particular solid booster, fluid-operated thrust nozzle, in particular water repulsion nozzle, winch for picking up or discharging a cable of the suspension device.The sensor unit is preferably an "IMU", i.e. an inertial measurement unit (IMU stands for "inertial measurement unit", i.e. inertial measurement device) and preferably has translatory and rotational accelerometers and position gyros for determining position angles, in particular a pitch angle and a roll angle of a platform-fixed coordinate system with respect to a ground-fixed coordinate system. Furthermore or alternatively preferably, the sensor unit has a device for detecting an optical flow, by means of which a relative movement of the platform with respect to a surroundings of the platform which are fixed to the earth is optically detected.The sensor unit thus acquires movement data, in particular a speed and / or an acceleration of the platform with respect to the earth-fixed environment of the platform, which are preferably transmitted as feedback signals ("feedback") into a position / and / or speed / and acceleration controller of the control unit for adjusting external disturbances and in particular the associated oscillations of the platform suspended on the supporting body in a manner pivotable under the influence of gravity, which are excited in particular by an external disturbance.The position controller of the sensor unit preferably has a feedback of a measured change in position with respect to the supporting body, which represents a proportional feedback, and a feedback of a speed of the platform with respect to an environment of the platform fixed to the earth or in each case preferably with respect to a coordinate system which is arranged fixedly to the supporting body on the body. The feedback of a speed thus represents the differential feedback of a derivative of the proportional feedback associated with the proportional feedback of a position, so that according to this embodiment artificial damping and artificial spring are produced by the control of the control unit. Alternatively, it is also possible to carry out only a proportional feedback or else only a differential feedback. Alternatively, it is preferably also possible to use a different control method, in each case in particular depending on the actuators available. Thus, for example, a model follow-up control can also be implemented in which a desired behavior, for example in the form of a differential equation, is explicitly defined.It is an advantageous effect of the invention that the robot manipulator, which is guided by the supporting body, can carry out precise manipulations, since in particular the platform supporting the robot manipulator is stabilized by the adjusting out of undesired movements of the platform. Possible advantageous applications of such a platform are the inspection and maintenance of hazardous zones in industrial installations, the air-assisted maintenance of high-level installations to which industrial climbing machines would otherwise be necessary, and the transport of objects which require a manipulation task during transport, and further manipulation tasks in zones which are difficult to access by humans only under danger or otherwise.According to an advantageous embodiment, the suspension device has a plurality of strands and the actuator unit comprises at least one winch for lengthening or shortening at least one of the strands, wherein the control unit is designed to actuate the winch for compensating a change in the overall center of gravity of platform and robot manipulator caused by movement of the robot manipulator.The total center of gravity is preferably defined in a body-fixed coordinate system arranged notionally on the platform. The overall center of gravity of platform and robot manipulator changes in particular into a surface normal perpendicular to the platform in a plane of the platform upon deflection of at least one member of the robot manipulator relative to a surface normal.According to a further advantageous embodiment, the actuator unit has at least one mass movable with respect to the platform, wherein the control unit is designed to actuate the movable mass in order to compensate for a change in the overall center of gravity of platform and robot manipulator caused by movement of the robot manipulator.Preferably, the movable mass is movable in a plane of the substantially flat platform.According to a further advantageous embodiment, the actuator unit has at least one propeller, wherein the control unit is designed to actuate the at least one propeller.Preferably, exactly one propeller is arranged on the platform, which preferably acts in a yaw movement of the platform. The yaw movement is a movement about a vertical axis of the platform, in particular about a gravity vector in the case of a horizontal orientation of the platform.Exactly one propeller is sufficient for this embodiment if the one propeller can generate both a tractive force and a compressive force, for example, by adjusting the blades or reversing the direction of the motor. If, on the other hand, propellers and motors are used which can generate thrust only in one direction, that is to say without thrust reversal, it is expediently preferred to provide, instead of the exactly one propeller, a propeller pair, of which one of the propellers serves to generate a tractive force and the other propeller of the propeller pair serves to generate a compressive force which is opposite the tractive force.Alternatively preferably, the platform has up to eight propellers, which can act at least partially redundantly about an axis or in one direction.Further preferably, at least one propeller is arranged in a longitudinal direction and one propeller is arranged in a transverse direction of the platform, wherein the longitudinal direction and the transverse direction of the platform together form a plane of a substantially flat platform and are perpendicular to each other.According to a further advantageous embodiment, the control unit is designed to actuate the movable mass and / or the winch for setting a trimming force and / or a trimming moment acting on the platform for disturbances with low frequencies detected by the sensor unit, and to actuate the propellers for adjusting these disturbances for disturbances with higher frequencies.According to a further advantageous embodiment, the platform further comprises a foldable landing gear.According to a further advantageous embodiment, the propeller is arranged on the retractable landing gear. Advantageously, a propeller arm and the respective leg of the landing gear are hereby combined into one and the same component.According to a further advantageous embodiment, the robot manipulator is arranged on an underside of the platform and the suspension device is arranged on an upper side of the platform.A further aspect of the invention relates to a flight unit, having a rotorcraft as a supporting body, which is connected to a platform (as described above and below) via the suspension device of the platform.The rotorcraft can in particular be a helicopter in main / tail rotor configuration, a helicopter in coaxial rotor configuration, a multicopter such as a quadrocopter, hexacopter or octocopter, or a missile with a sheathed propeller or with thrust nozzles.Alternatively preferably, instead of the rotorcraft, an airship is used which, instead of the dynamic buoyancy of the rotorcraft, generates static buoyancy by holding a gas of lower density than the air density.Advantages and preferred refinements of the proposed flight unit result from an analogous and analogous transfer of the explanations given above in connection with the proposed platform.A further aspect of the invention relates to a method for controlling or regulating faults on a platform having a robot manipulator arranged on the platform and having a suspension device, wherein the suspension device is designed to mount the platform on a supporting body by forming a suspension such that, under the influence of gravity, the suspension allows a pendulum movement of the platform with respect to the supporting body, having the steps:controlling the robot manipulator by a control unit,acquiring movement data of the platform by a sensor unit and transmitting the movement data to the control unit, andactivating an actuator unit of the platform by the control unit on the basis of the movement data recorded by the sensor unit in order to exert a force opposing an undesired movement of the platform and / or an opposing torque by the actuator unit.According to an advantageous embodiment, the platform furthermore has a foldable landing gear and the actuator unit has at least one propeller, wherein the propeller is arranged on the foldable landing gear. Furthermore, the method according to this embodiment further comprises the steps:activating the robot manipulator into a landing pose for supporting the platform with respect to a ground when depositing the platform onto the ground, andcontrolling the landing gear from a folded-in state into a folded-out state for supporting the platform with respect to a ground when the platform is placed on the ground.Advantages and preferred refinements of the proposed method result from an analogous and analogous transfer of the statements made above in connection with the proposed platform.Further advantages, features and details are evident from the following description, in which--possibly with reference to the drawing--at least one exemplary embodiment is described in detail. Identical, similar and / or functionally identical parts are provided with the same reference numerals.The following are shown: FIG. 1 shows a flight unit according to an exemplary embodiment of the invention, FIG. 2 shows a platform suspended from a crane according to a further exemplary embodiment of the invention, and FIG. 3 shows a method for controlling or regulating faults on a platform according to a further exemplary embodiment of the invention.The representations in the figures are schematic and not to scale.FIG. 1 shows a flight unit, having a helicopter drone as a supporting body 20, which is connected to a platform 1 via ropes of a suspension device 5 of the platform 1. The platform 1 has a robot manipulator 3 on its underside and the suspension device 5 on its upper side, wherein the suspension device 5 is designed to mount the platform 1 on the supporting body 20 by forming a suspension consisting of three ropes, so that the ropes are tensioned under the influence of gravity and are suspended on a central load hook of the helicopter drone in order to allow a pendulum movement of the platform 1 relative to the supporting body 20. Furthermore, the platform 1 has a control unit 10 with an inertial sensor unit 11 connected thereto, which is designed for capturing movement data of the platform 1 and for transmitting the movement data to the control unit 10. Furthermore, a plurality of actuators combined as an actuator unit 12 are arranged on the platform 1, which is designed to exert a force and / or a torque on the platform 1 and can be controlled by the control unit 10. As actuators of the actuator unit 12 a propeller, a movable mass and three cable winch are shown, wherein the movable mass is movable in the directions of the dashed double arrow, i.e. in a longitudinal direction of the platform 1. The control unit 10 is designed to control the winch and the movable mass in order to compensate for a change in the overall center of gravity of the platform 1 and robot manipulator 3 caused by movement of the robot manipulator 3.The control unit 10 is furthermore designed to actuate the motors at the joints of the robot manipulator 3 and to actuate the propellers on the basis of the movement data recorded by the sensor unit 11 for exerting a force and / or a torque directed opposite to an undesired movement of the platform 1. Furthermore, a folding landing gear 13 is arranged on the platform 1, which at the same time serves as a propeller arm in the flying operation of the flight unit.FIG. 2 shows a platform 1 suspended on a crane as a supporting body 20, the crane being connected to the platform 1 via crane lines of a suspension device 5. The platform 1 has on its underside a pneumatically controllable robot manipulator 3 and on its upper side the suspension device 5. Furthermore, the platform 1 has a control unit 10 with an inertial sensor unit 11 connected thereto, which is designed for capturing movement data of the platform 1 and for transmitting the movement data to the control unit 10. Furthermore, a plurality of actuators combined as actuator unit 12 are arranged on the platform 1, which is designed to exert forces and moments on the platform 1 and can be controlled by the control unit 10. Actuators of the actuator unit 12 are shown to be a propeller representative of a plurality of propellers, a movable steel mass and three cable winch, the movable mass being movable in the directions of the dashed double arrow, i.e. in a longitudinal direction of the platform 1. The control unit 10 is designed to control the winch and the movable mass in order to compensate for a change in the overall center of gravity of the platform 1 and robot manipulator 3 caused by movement of the robot manipulator 3. The control unit 10 is furthermore designed to actuate the pneumatic throttles at the joints of the robot manipulator 3 and to actuate the propellers on the basis of the movement data recorded by the sensor unit 11 for exerting a force and / or a torque directed opposite to an undesired movement of the platform 1.FIG. 3 shows a method for controlling or regulating faults on a platform 1 with a robot manipulator 3 arranged on the platform 1 and with a suspension device 5, wherein the suspension device 5 is designed to mount the platform 1 on a supporting body 20 by forming a suspension, so that under the influence of gravity the suspension allows a pendulum movement of the platform 1 relative to the supporting body 20, comprising the steps:controlling S1 of the robot manipulator 3 by a control unit 10,acquiring S 2 movement data of the platform 1 by a sensor unit 11 and transmitting the movement data to the control unit 10, andActuation S 3 of an actuator unit 12 of the platform 1 by the control unit 10 on the basis of the movement data recorded by the sensor unit 11 for exerting a force opposing an undesired movement of the platform 1 and / or an opposing moment by the actuator unit 12. Before the platform 1 is placed on a floor beneath the platform 1, the following steps are carried out:activating S 4 the robot manipulator 3 into a landing pose for supporting the platform 1 with respect to a ground when depositing the platform 1 on the ground, andactivating S 5 of the landing gear 13 from a folded-in state into a folded-out state for supporting the platform 1 with respect to a ground when the platform 1 is placed on the ground.List of reference characters1 Platform 3 Robot manipulator 5 Suspension device 10 Control unit 11 Sensor unit 12 Actuator unit 13 Landing gear 20 Supporting body S 1 Actuation S 2 Detection S 3 Actuation S 4 Actuation S 5 Actuation

Claims

Platform (1) having a robot manipulator (3) arranged on the platform (1) and having a suspension device (5), wherein the suspension device (5) is designed to mount the platform (1) on a supporting body (20) by forming a suspension, such that the suspension allows a pendulum movement of the platform (1) with respect to the supporting body (20) under the influence of gravity, and wherein the platform (1) has: - a control unit (10), - a sensor unit (11) which is designed to acquire movement data of the platform (1) and to transmit the movement data to the control unit (10), and - an actuator unit (12) which is designed to exert a force and / or a moment on the platform (1) and is controllable by the control unit (10), wherein the control unit (10) is designed to transmit the movement data to the control unit (10), the robot manipulator (3) is controlled and the actuator unit (12) is controlled on the basis of the movement data recorded by the sensor unit (11) for exerting a force and / or a torque opposed to an undesired movement of the platform (1).Platform (1) according to claim 1, wherein the suspension device (5) has a plurality of strands and the actuator unit (12) comprises at least one winch for lengthening or shortening at least one of the strands, and wherein the control unit (10) is designed to control the winch for compensating a change in the overall center of gravity of platform (1) and robot manipulator (3) caused by movement of the robot manipulator (3).Platform (1) according to one of the preceding claims, wherein the actuator unit (12) has at least one mass which is movable with respect to the platform (1), and wherein the control unit (10) is designed to actuate the movable mass in order to compensate for a change in the overall center of gravity of the platform (1) and robot manipulator (3) caused by movement of the robot manipulator (3).Platform (1) according to one of the preceding claims, wherein the actuator unit (12) has at least one propeller, and wherein the control unit (10) is designed to actuate the propeller.Platform (1) according to any one of the preceding claims, wherein the platform (1) further comprises: - a collapsible landing gear (13).Platform (1) according to claims 4 and 5, wherein the propeller is arranged on the retractable landing gear (13).Platform (1) according to one of the preceding claims, wherein the robot manipulator (3) is arranged on an underside of the platform (1) and the suspension device (5) is arranged on an upper side of the platform (1).Flight unit, comprising a rotorcraft as a support body (20), which is connected to a platform (1) according to one of Claims 1 to 7 via the suspension device (5) of the platform (1).Method for controlling or controlling faults on a platform (1) with a robot manipulator (3) arranged on the platform (1) and with a suspension device (5), wherein the suspension device (5) is designed to mount the platform (1) on a supporting body (20) by forming a suspension, such that under the influence of gravity the suspension allows a pendulum movement of the platform (1) with respect to the supporting body (20), comprising the steps: - actuation (S1) of the robot manipulator (3) by a control unit (10), - acquisition (S2) of movement data of the platform (1) by a sensor unit (11) and transmission of the movement data to the control unit (10), and - actuation (S3) of an actuator unit (12) of the platform (1) by the control unit (10) on the basis of the movement data detected by the sensor unit (11) for the purpose of exerting a force opposing an undesired movement of the platform (1) and / or an opposing torque by the actuator unit (12).Method according to claim 9, wherein the platform (1) further comprises a foldable landing gear (13) and the actuator unit (12) comprises at least one propeller, and wherein the propeller is arranged on the foldable landing gear (13), wherein the method further comprises the steps of: - driving (S4) the robot manipulator (3) into a landing pose for supporting the platform (1) with respect to a ground when depositing the platform (1) onto the ground, and - driving (S5) the landing gear (13) from a folded into a deployed state for supporting the platform (1) with respect to a ground when depositing the platform (1) onto the ground.

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