Movable hydraulic mechanical arm and control method

Abstract

The invention provides a movable hydraulic mechanical arm and a control method, and the mechanical arm comprises a base which adopts the design of a movable chassis with an independent drive, so that the equipment moving capability is provided. The arm support assembly is formed by connecting a plurality of arm supports in series through rotary joints, and each joint is provided with a hydraulic actuator to achieve the driving function. The sensing and positioning system is responsible for obtaining the state of the mechanical arm and surrounding three-dimensional environment information and providing data support for intelligent control. The control system is arranged on the arm support and connected with the subsystems through cables, and cooperative motion control based on state information and environment information is achieved. The hydraulic system comprises three core assemblies, wherein hydraulic power units are in one-to-one correspondence with the actuators; the hydraulic execution unit is integrated on an actuator oil port valve block and comprises a servo valve, a pressure sensor and an emergency locking valve. The hydraulic auxiliary unit provides oil storage, temperature control and filtering functions. The key problems of dynamic coupling, response delay, low energy efficiency and the like are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydraulic mechanical arm control, and in particular relates to a mobile hydraulic mechanical arm and a control method thereof. Background Art

[0002] Currently, robotic arms have replaced manual labor in many fields. However, in heavy-duty applications such as construction machinery, mining machinery, and agricultural machinery, hydraulic robotic arms, while widely adopted due to their high power density, still face severe technical bottlenecks. Traditional heavy-duty hydraulic robotic arms generally utilize centralized hydraulic systems, where a central pump station supplies oil to multiple actuators (hydraulic cylinders or motors) through complex piping and valve systems.

[0003] This architecture has inherent flaws: first, when each actuator moves, it will produce serious dynamic coupling interference through the shared hydraulic pipeline. The load change of one joint will directly affect the pressure and flow of other joints, making it difficult to improve control accuracy; second, the existence of long-distance hydraulic pipelines and multi-stage valve groups causes significant pressure loss and dynamic response delay, making the robot arm move slowly and difficult to achieve fast and precise automated control; finally, the system needs to maintain a high pressure state at all times to cope with peak loads, resulting in low energy efficiency and huge energy waste most of the time.

[0004] Therefore, most existing heavy hydraulic robotic arms remain in the semi-automatic stage where they are manually operated by operators. Their operating efficiency, construction quality, and operation accuracy are far from meeting the modern industry's demand for automated and refined operations, and also bring about higher labor costs and potential safety risks. Summary of the Invention

[0005] The present invention provides a mobile hydraulic mechanical arm and a control method to solve the above technical problems.

[0006] In a first aspect, the present invention provides a mobile hydraulic mechanical arm, comprising an arm assembly, a base, a sensing and positioning system, a hydraulic system, and a control system; The base is a movable chassis with an independent driving device; The arm assembly is arranged on a base and is composed of at least two arms connected in series via a rotary joint, and each rotary joint is integrated with a hydraulic actuator for driving; The sensing and positioning system is used to obtain the state information of the robot arm and the three-dimensional environment information around the robot arm; The control system is provided on the boom assembly and is electrically connected to the hydraulic system, the base, and all sensors and hydraulic actuators on the boom assembly via cables, and is used to coordinately control the movement of the mobile hydraulic manipulator arm by combining its own state information and external environment information; The hydraulic system is provided on the boom assembly and includes: a plurality of hydraulic power units corresponding one to each hydraulic actuator of the boom assembly, each hydraulic power unit comprising a servo motor, a quantitative hydraulic pump connected to the servo motor via a bell housing and a coupling, an accumulator installed at the outlet of the quantitative hydraulic pump, and a first pressure sensor; Multiple hydraulic actuator units are integrated on the oil port valve block of the corresponding hydraulic actuator, each hydraulic actuator unit includes a servo valve, a second pressure sensor installed at two working oil ports of the servo valve, and a solenoid switch valve for emergency locking; The hydraulic auxiliary unit includes an oil tank with a liquid level and temperature sensor, a forced refrigeration circulation system consisting of a fan and a compressor driven by a frequency converter, and a filter arranged on the total oil return line.

[0007] Optionally, the perception and positioning system includes: An environmental perception unit, consisting of at least one laser radar installed on the base or the end of the arm assembly, is used to scan and build a three-dimensional point cloud map around the robotic arm in real time; The global positioning unit, consisting of an RTK receiver and receiver antenna mounted on the boom assembly, is used to obtain the absolute position of the robotic arm in the world coordinate system; The attitude sensing unit is composed of multiple inertial measurement units installed on the base and each arm respectively, which is used to measure the pitch, roll and yaw angles of the base and each arm in real time; The proprioception unit consists of a joint angle sensor installed coaxially with each rotary joint and a cylinder stroke sensor built into each hydraulic actuator, and is used to measure the real-time joint posture information of each rotary joint.

[0008] Optionally, each rotating joint of the arm assembly adopts an integrated structure, and the integrated structure includes: Hydraulic actuator, which is a hydraulic cylinder or hydraulic motor; An integrated valve block installed at the oil port of the hydraulic actuator, wherein the servo valve, the second pressure sensor and the electromagnetic switch valve are all installed on the integrated valve block; A joint angle sensor or a cylinder stroke sensor in the proprioception unit; an inertial measurement unit in the posture sensing unit; As well as, integrated wiring harnesses connecting all components in the integrated structure to the control system and integrated piping for hydraulic connections.

[0009] Optionally, the control system includes: a main controller, electrically connected to the sensing and positioning system, for fusing multi-source sensor data and performing motion planning including vibration prediction and suppression based on a pre-stored multi-body dynamics model, to generate a drive torque sequence and a hydraulic energy supply strategy; Multiple joint controllers, one corresponding to each hydraulic actuator, the command input terminals of all joint controllers are connected to the main controller and are used to receive the drive torque sequence, the feedback input terminals of all joint controllers are connected to the sensors in the corresponding proprioception unit and hydraulic actuator unit, and all joint controllers are equipped with a hydraulic stiffness observer for online analysis of hydraulic stiffness; A constant pressure and temperature controller, connected to the main controller, is used to receive and execute the hydraulic energy supply strategy, close the loop to control the speed of the servo motors in each hydraulic power unit, and adjust the cooling power according to the predictive thermal management instructions of the main controller; The safety controller is used to monitor all sensor signals and send a locking command to the solenoid switch valves of all hydraulic actuators when a hardware failure is detected. The command authority of the locking command is greater than the control commands issued by all other controllers in the control system.

[0010] In a second aspect, the present invention further provides a method for controlling a mobile hydraulic mechanical arm, which is applied to the mobile hydraulic mechanical arm described in any one of the first aspects, and the method comprises the following steps: Use the perception and positioning system to obtain the mobile hydraulic manipulator's own state information and the surrounding three-dimensional environment information; The control system processes the robot's own state information and three-dimensional environmental information, and plans the final motion trajectory of the mobile hydraulic manipulator. Using the control system to generate a hydraulic energy supply strategy according to the final motion trajectory, and instructing multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy; The control system is used to instruct multiple hydraulic execution units in the hydraulic system to drive the boom assembly to move along the final motion trajectory.

[0011] Optionally, the process of processing the self-state information and the three-dimensional environment information by using the control system and planning the final motion trajectory of the mobile hydraulic manipulator includes the following steps: The main controller integrates the multi-source sensor data obtained by the environmental perception unit, global positioning unit, posture perception unit and proprioception unit, and generates an initial motion trajectory according to the preset mission objectives; The main controller calls a pre-stored multi-body dynamics model containing the dynamic parameters of the boom assembly, takes the initial motion trajectory as input, and predicts the vibration response of each boom of the boom assembly when executing the initial motion trajectory; If the predicted vibration response exceeds a preset response threshold, the velocity and acceleration profiles of the initial motion trajectory are adjusted by the main controller using an optimization algorithm to generate a final motion trajectory that actively suppresses structural vibration.

[0012] Optionally, the step of generating a hydraulic energy supply strategy based on the final motion trajectory using the control system and instructing multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy comprises the following steps: The master controller combines the final motion trajectory with the multi-body dynamics model to calculate the time-varying drive torque sequence of each revolute joint in the process of achieving the final motion trajectory. The driving torque sequence is resolved into a power demand curve for each hydraulic power unit by the main controller; generating a feedforward energy scheduling strategy for the servo motor in each hydraulic power unit according to the power demand curve through the main controller; A feedforward energy scheduling strategy is executed by a constant pressure and constant temperature controller. When the output power of the rotary joint exceeds a preset first power threshold, the speed of the servo motor corresponding to the rotary joint is advanced, and the accumulator is charged with pressure through a quantitative hydraulic pump. When the output power of the rotary joint is lower than a preset second power threshold, the speed of the servo motor corresponding to the rotary joint is reduced, and the first power threshold is greater than the second power threshold. During the execution of the feedforward energy scheduling strategy, the first pressure value of the first pressure sensor in each hydraulic power unit is continuously monitored by the constant pressure and constant temperature controller, and the speed of the servo motor is closed-loop corrected according to the first pressure value.

[0013] Optionally, parsing the driving torque sequence into a power demand curve of each hydraulic power unit by the main controller includes the following steps: The main controller obtains real-time joint posture information provided by the joint angle sensor and the cylinder stroke sensor in the proprioception unit, wherein the real-time joint posture information includes relative rotation angle and telescopic length; A nonlinear mapping model is established by the main controller based on the geometric size parameters of the boom assembly, which converts the driving torque of each rotary joint into the required output force of the corresponding hydraulic actuator. The main controller converts the driving torque sequence into the target output force sequence required by each hydraulic actuator in real time through a nonlinear mapping model; The main controller converts the target output force sequence into the target pressure difference sequence required by the inlet and outlet ports of each hydraulic actuator according to the effective action area of ​​each hydraulic actuator; The target pressure difference sequence is combined with the target movement speed of the hydraulic actuator by the main controller to calculate the power demand curve of each hydraulic power unit that varies with time.

[0014] Optionally, the step of using the control system to instruct multiple hydraulic actuators in the hydraulic system to drive the boom assembly to move along the final motion trajectory includes the following steps: The final motion trajectory is sent to each joint controller through the main controller as the target instruction for the position control of the joint controller; For any joint controller, preliminary closed-loop control is performed on the servo valve in the corresponding hydraulic actuator unit through the key controller in combination with the target command and real-time joint posture information; During the preliminary closed-loop control process, the joint controller reads the second pressure value of the corresponding second pressure sensor, and calculates the real-time pressure difference acting on the hydraulic actuator based on the second pressure value; The joint controller uses a built-in hydraulic stiffness observer to analyze the dynamic relationship between the servo valve control command, real-time pressure difference and real-time joint posture information, and calculates the equivalent hydraulic stiffness of the current rotary joint. When the equivalent hydraulic stiffness is lower than the preset hydraulic stiffness threshold, the joint controller adjusts the closed-loop control parameters of the preliminary closed-loop control according to the equivalent hydraulic stiffness, and requests the constant pressure and constant temperature controller to increase the reference pressure of the corresponding hydraulic power unit for stiffness compensation.

[0015] Optionally, the method further comprises the following steps: The safety controller monitors the readings of all sensors in the perception and positioning system and the hydraulic system, as well as the actual motion trajectory of the mobile hydraulic manipulator in real time and in parallel; If the value of any sensor exceeds the preset danger threshold or the trajectory deviation between the actual motion trajectory and the final motion trajectory exceeds the preset deviation threshold, the safety controller will send a locking command with the highest authority to the solenoid switch valves of all hydraulic actuators on the boom assembly; When the solenoid switch valve receives the locking command, it locks the oil circuits of all hydraulic actuators to freeze the current state of the boom assembly.

[0016] The beneficial effects of the present invention are: The present invention completely solves the inherent defects of traditional centralized systems by adopting a distributed hydraulic architecture. Each actuator is equipped with an independent power unit, which fundamentally eliminates the power coupling interference between the joints, realizes independent control in the true sense, and greatly improves the control accuracy and response speed. The present invention significantly shortens the hydraulic transmission distance by arranging the power source nearby, effectively reduces the pressure loss and transmission delay, and enables the robotic arm to achieve fast and accurate action response, meeting the strict requirements of automated operations. The present invention adopts an intelligent control strategy of on-demand energy supply, which avoids the energy waste of traditional systems that continuously maintain a high-pressure state, and dynamically adjusts the output of each power unit according to the actual load demand, significantly improving the energy efficiency of the system. The present invention integrates advanced sensing and positioning systems and intelligent control systems, realizing the leap from semi-automation to full automation, which not only improves work efficiency and construction quality, but also greatly reduces labor costs and safety risks. The mobile design of the present invention enhances the applicability and flexibility of the equipment and can adapt to the needs of various complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of a mobile hydraulic robotic arm in one embodiment of the present application.

[0018] Figure 2 This is a structural diagram of the first arm base end and the base in one embodiment of the present application.

[0019] Figure 3 This is a schematic structural diagram of the second arm and the third arm in one embodiment of the present application.

[0020] Figure 4 In one embodiment of this application Figure 3 An enlarged schematic diagram of the structure of the second boom portion.

[0021] Figure 5 This is a schematic diagram of the internal architecture of a control system in one embodiment of the present application.

[0022] Figure 6 This is a structural diagram of a hydraulic system in one embodiment of the present application.

[0023] Figure 7 This is a flow chart of a method for controlling a mobile hydraulic robotic arm in one embodiment of the present application.

[0024] Description of reference numerals: 1. Base; 2. Boom assembly; 21. First boom; 22. Second boom; 23. Third boom; 3. Control system; 4. Hydraulic system; 51. First laser radar; 52. First attitude sensor; 53. Relative positioning device; 54. Second laser radar; 55. Horizontal positioner; 56. First hollow magnetic ring angle encoder; 6. Base rotation joint; 7. Spring expansion shock absorber; 8. Hydraulic motor; 81. Rotary drive oil pipe; 82. Rotary drive wiring harness port; 83. Rotary drive pressure sensor; 84. Rotary drive solenoid switch valve; 85. Rotational drive brake valve block; 86. Rotational drive hydraulic servo valve; 9. Counterweight; 10. Upper base; 11. First RTK; 31. Electrical control box; 32. Remote controller; 33. Warning light; 34. Third laser radar; 211. First boom cylinder; 212. First boom cylinder oil pipe; 213. First boom rotation joint; 214. Second hollow magnetic ring angle encoder; 215. Fourth laser radar; 216. First tilt sensor; 12. Second RTK; 221. Second boom cylinder; 222. Second boom rotation joint. 223, third hollow magnetic ring angle encoder; 224, fifth laser radar; 231, third boom cylinder; 232, third boom cylinder oil pipe; 233, first ultrasonic radar; 234, second tilt sensor; 235, third boom rotation joint; 236, fourth hollow magnetic ring angle encoder; 13, flow meter; 14, second ultrasonic radar; 15, discharge port rotation joint; 16, second attitude sensor; 17, infrared camera; 18, automatic door valve; 19, discharge hose; 225, second boom cylinder oil pipe; 226, second Boom cylinder wiring harness port; 227, third ultrasonic radar; 2211, second boom cylinder pressure sensor; 2212, second boom cylinder solenoid switch valve; 2213, second boom cylinder brake valve block; 2214, second boom cylinder hydraulic servo valve; 2215, second boom cylinder stroke sensor; 41, oil tank; 42, liquid level and temperature sensor; 43, oil outlet pipe; 44, forced refrigeration circulation system; 45, accumulator; 46, hydraulic drive power valve block; 47, servo drive module; 48, integrated servo motor; 49, gear pump. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of this application to clearly describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0026] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0027] Reference Figure 1 The embodiment of the present invention provides a mobile hydraulic mechanical arm, which has the characteristics of high precision, high efficiency, high dynamic response and high safety, and can adapt to the needs of automated operations in open, unstructured and complex working environments. Figure 1 As shown, the mobile hydraulic robotic arm includes an arm assembly 2, a base 1, a sensing and positioning system, a hydraulic system 4 and a control system 3. These five systems work together to form the technical solution of the present invention. The base 1 is the mobile platform of the entire equipment, providing carrying capacity and off-road maneuverability. The arm assembly 2 is the main actuator for realizing the operating function and is installed on the base 1. The hydraulic system 4 provides a power source for the movement of the arm assembly 2, and some of its components are also installed on the base 1. The sensing and positioning system gives the robotic arm the ability to perceive the environment and its own state. The control system 3 serves as the brain of the entire equipment, coordinating various subsystems to realize complex autonomous or semi-autonomous operating tasks.

[0028] The base 1 is a movable chassis with an independent drive device. Figure 1 and Figure 2 As shown, the base 1 adopts a crawler structure to adapt to different working ground environments, such as construction sites, mines or rugged fields. An upper base 10 is installed on the base 1, and the arm assembly 2 is connected to the upper base 10 through a base rotating joint 6. The base 1 integrates an independent power and drive system, such as an internal combustion engine or a high-power electric motor to drive a hydraulic pump, and then drives the crawler through a hydraulic motor, thereby realizing the autonomous movement of the mobile hydraulic robotic arm. The base 1 is also equipped with a structure for supporting and balancing the entire robotic arm, such as a retractable hydraulic support leg and a spring retractable shock absorber 7, and a counterweight block 9 arranged at the rear of the upper base 10, which is used to balance the unbalanced torque generated by the movement of the arm assembly 2. As shown Figure 2As shown, base 1 also integrates some components of the perception and positioning system, such as a first laser radar 51 mounted on the front of the chassis and a second laser radar 54 mounted on the rear, as well as a relative positioning device 53 and a horizontal positioner 55. These are used to collect terrain data and obstacle information, providing a basis for subsequent movement path planning and safe obstacle avoidance. Furthermore, base 1 is also equipped with a first attitude sensor 52 for real-time monitoring of the chassis' pitch and roll attitude. This is crucial for compensating for the impact of chassis attitude changes on the accuracy of the end of boom assembly 2 when operating on uneven ground.

[0029] The arm assembly 2 is arranged on the base 1 and is composed of at least two arms connected in series through a rotating joint, and each rotating joint is integrated with a hydraulic actuator for driving. Figure 1 and Figure 3 As shown, the boom assembly 2 consists of multiple boom sections connected in series, including a first boom 21, a second boom 22, and a third boom 23. Rotational motion is achieved through a base rotation joint 6 mounted on the base 1. The first boom 21 is connected to the upper base 10 via a first boom rotation joint 213; the second boom 22 is connected to the first boom 21 via a second boom rotation joint 222; and the third boom 23 is connected to the second boom 22 via a third boom rotation joint 235. This multi-degree-of-freedom configuration enables the robotic arm to have a wide operating range and flexible posture adjustment capabilities. The connecting joints between the booms utilize different types of hydraulic actuators depending on the type of motion. For example, the hydraulic actuator for the revolute joints used to achieve the boom's pitch motion is a high-thrust hydraulic cylinder. Specifically, the first boom rotation joint 213 is driven by the first boom cylinder 211, the second boom rotation joint 222 is driven by the second boom cylinder 221, and the third boom rotation joint 235 is driven by the third boom cylinder 231. The corresponding hydraulic oil pipelines include the first boom cylinder pipeline 212, the second boom cylinder pipeline 225, and the third boom cylinder pipeline 232. The hydraulic actuator for the base rotation joint 6, which enables the overall left and right rotation of the boom assembly 2 on the base 1, is a hydraulic motor 8, which drives the slewing bearing through a reducer. Integrating the hydraulic actuator directly into the joint significantly shortens the hydraulic pipeline length and reduces the negative effects of the elasticity, viscosity, and inertia of the hydraulic oil, thereby improving the system's dynamic response speed and control accuracy.

[0030] The boom itself can utilize an integrated, foldable truss structure. This design reduces weight while maintaining structural rigidity, thereby increasing payload capacity and reducing energy consumption. Channels for accommodating conduits can be designed inside or outside the boom, effectively protecting hydraulic oil lines and cables from scratches or damage in harsh working environments and improving system reliability. At the end of the boom assembly 2, namely the end of the third boom 23, is a work tool. In this embodiment, it includes a discharge hose 19 connected via a discharge port rotating joint 15. Its flow rate is controlled by an automatic gate valve 18 and can be monitored by a flow meter 13.

[0031] The perception and positioning system is used to obtain information about the robot's own state and the three-dimensional environment surrounding it. This state information primarily includes the angles or displacements of each joint, as well as the attitude angles of each arm frame and base 1. External three-dimensional environmental information includes the terrain, fixed obstacles, and moving objects within the robot's operating space. The perception and positioning system is fundamental to the robot's autonomous operation, providing the control system 3 with all the internal and external information necessary for decision-making and planning. By integrating this multi-source information, the control system 3 can establish a precise understanding of itself and its environment, thereby planning a safe and efficient motion trajectory.

[0032] The control system 3 is arranged on the boom assembly 2. Specifically, its core components such as the main controller and the safety controller are integrated in the electric control box 31 installed on the upper base 10. The control system 3 is electrically connected to the hydraulic system 4, the base 1 and all sensors and all hydraulic actuators on the boom assembly 2 through cables, and is used to coordinate the movement of the mobile hydraulic robotic arm by combining its own status information and external environmental information. The operator can interact with the control system 3 through the remote controller 32 to issue instructions and monitor the status. A warning light 33 is also provided on the electric control box 31 to intuitively display the working status or alarm information of the equipment. The core components of the control system 3, especially the joint controller, are arranged on the boom assembly 2, close to the corresponding actuators and sensors. This distributed control architecture can greatly reduce the delay and interference of signal transmission, and improve the real-time and robustness of the control loop. Connections between controllers, as well as between controllers and sensors and actuators, are achieved through integrated wiring harnesses, such as those through interfaces such as the rotary drive harness port 82 and the second boom cylinder harness port 226. These harnesses are properly arranged and protected to ensure reliability during the robot's movement. The control system 3 receives data from the sensing and positioning system and, through complex algorithmic processing, generates coordinated control instructions for base 1 movement, boom posture, and end-of-line tool operation. These instructions are then transmitted via cables to the corresponding drive units, such as the base 1 drive device and the hydraulic actuator on the boom assembly 2, forming a complete closed loop of information perception, decision-making planning, and action execution.

[0033] The hydraulic system 4 is arranged on the boom assembly 2, and its main power unit and auxiliary equipment such as the oil tank are also installed at the rear of the upper base 10. This layout, especially the design of distributing the hydraulic power units on the boom, is an important feature of the present invention. It subverts the centralized oil supply mode of traditional engineering machinery where a huge central hydraulic pump station is set on the base. This distributed energy supply design concept enables each actuator to have a nearby, independent power source, thereby completely solving the problems of energy loss, pressure fluctuation and dynamic response lag caused by long-distance hydraulic pipelines. The hydraulic system 4 is mainly composed of three parts: multiple hydraulic power units, multiple hydraulic execution units and hydraulic auxiliary units.

[0034] Specifically, the hydraulic system 4 includes multiple hydraulic power units, one corresponding to each hydraulic actuator in the boom assembly 2. This one-to-one configuration is the core of achieving distributed drive and energy management. Each hydraulic power unit consists of a servo motor, a fixed-displacement hydraulic pump connected to the servo motor via a bell housing and a coupling, an accumulator mounted at the outlet of the fixed-displacement hydraulic pump, and a first pressure sensor. In this structure, the servo motor is the power source, receiving speed commands from the control system 3 and capable of very precise and rapid adjustment of the output speed. The fixed-displacement hydraulic pump, such as a high-pressure gear pump, has an output flow rate proportional to the input speed. The servo motor and fixed-displacement hydraulic pump are rigidly connected via a bell housing and a coupling, forming a compact electro-hydraulic power system. The servo motor's precise control of the fixed-displacement hydraulic pump's speed is equivalent to precisely controlling the output flow rate of the hydraulic oil, thereby achieving "oil on demand" and greatly improving energy utilization efficiency. The accumulator mounted at the outlet of the fixed-displacement hydraulic pump primarily absorbs pressure fluctuations caused by pump pulsation and sudden load changes, stabilizing system pressure and replenishing energy when the actuator requires instantaneous high flow rates. The first pressure sensor monitors the power unit's outlet pressure in real time and feeds the pressure signal back to control system 3, forming a closed-loop pressure control system. Based on this feedback signal, control system 3 dynamically adjusts the servo motor's speed to maintain a constant outlet pressure, thereby providing a stable and reliable hydraulic energy source for the downstream hydraulic actuator.

[0035] The hydraulic system 4 also includes a plurality of hydraulic actuator units, which are integrated on the oil port valve blocks of the corresponding hydraulic actuators. Figure 2 and Figure 4As shown, this highly integrated design minimizes the distance between the control valve and the actuator, thereby achieving optimal control performance. Each hydraulic actuator unit includes a servo valve, second pressure sensors mounted at the servo valve's two working oil ports, and a solenoid switch valve for emergency locking. Taking the second boom cylinder 221, which drives the second boom 22, as an example, the components of its hydraulic actuator unit are integrated into the second boom cylinder brake valve block 2213, which is directly mounted on the cylinder body. These components include the second boom cylinder hydraulic servo valve 2214, the second boom cylinder pressure sensor 2211, and the second boom cylinder solenoid switch valve 2212. The servo valve, such as the high-response second boom cylinder hydraulic servo valve 2214, is a key component for achieving precise motion control. It receives weak current signals from the joint controller and precisely controls the flow and direction of the two oil chambers in the second boom cylinder 221, thereby controlling the actuator's motion speed and direction. The second pressure sensor, such as the second boom cylinder pressure sensor 2211, is used to monitor the hydraulic actuator's operating pressure in real time. The difference in these pressure signals directly reflects the size and direction of the external load borne by the actuator, and is important feedback information for achieving force control, compliance control, and dynamic load compensation. The electromagnetic switch valve used for emergency locking, such as the second arm cylinder electromagnetic switch valve 2212, is connected in parallel to the oil circuit of the actuator. Once the safety controller detects any fault that may endanger safety, it will immediately send a locking command to the electromagnetic switch valve, so that the current posture of the robotic arm is instantly locked to prevent accidents due to loss of control. Similarly, the hydraulic motor 8 that drives the base rotation joint 6 is also equipped with a similar hydraulic actuator unit, including a rotary drive hydraulic servo valve 86 integrated on the rotary drive brake valve block 85, a rotary drive pressure sensor 83, and a rotary drive electromagnetic switch valve 84.

[0036] The hydraulic system 4 also includes a hydraulic auxiliary unit, which provides support and protection for the entire hydraulic system 4. The hydraulic auxiliary unit includes an oil tank 41 with a liquid level and temperature sensor 42, a forced refrigeration circulation system 43 consisting of a fan and compressor driven by a frequency converter, and a filter installed on the main return oil line. The oil tank 41 is used to store hydraulic oil and plays a role in heat dissipation and precipitation of impurities. The liquid level and temperature sensor 42 installed on it monitors the oil volume and oil temperature in the oil tank 41 in real time, providing oil status information to the control system 3, and realizing low liquid level alarms and high temperature warnings. The forced refrigeration circulation system 43 can accurately adjust the cooling power according to the instructions issued by the thermostat controller to ensure that the oil temperature is always stable in the optimal working range. The filter installed on the main return oil line is used to filter out impurity particles in the return oil and maintain the cleanliness of the hydraulic oil. This is a necessary condition for ensuring the normal operation of precision hydraulic components such as servo valves.

[0037] In a more specific embodiment, the perception and positioning system is described in detail. The perception and positioning system includes an environment perception unit, a global positioning unit, a posture perception unit, and a body perception unit. These four units work together to provide the robot arm with comprehensive spatiotemporal perception capabilities. Among them, the environment perception unit is composed of at least one laser radar installed at the base 1 or the end of the arm assembly 2, which is used to scan and establish a three-dimensional point cloud map around the robot arm in real time. Figure 2 and Figure 3 As shown, this embodiment is equipped with multiple laser radars, including a first laser radar 51 and a second laser radar 54 mounted on the base 1, a third laser radar 34 mounted on the upper base 10, a fourth laser radar 215 mounted on the first boom 21, and a fifth laser radar 224 mounted on the second boom 22. This enables all-round, comprehensive scanning of the entire machine's surroundings. Furthermore, the environmental perception unit also includes multiple ultrasonic radars as supplementary components, such as a first ultrasonic radar 233 mounted on the third boom 23, a second ultrasonic radar 14 mounted at the boom end, and a third ultrasonic radar 227 mounted near the second boom cylinder 221 for close-range obstacle detection. An infrared camera 17 is also mounted at the boom end, providing rich image information.

[0038] The global positioning unit consists of an RTK receiver and a receiver antenna, and is used to obtain the absolute position of the robotic arm in the world coordinate system. Figure 2 and Figure 3 As shown, this embodiment is equipped with a first RTK 11 and a second RTK 12. The first RTK 11 is mounted at the highest point of the upper base 10, while the second RTK 12 is mounted on the first boom 21. Using dual-antenna positioning technology, it not only obtains centimeter-level absolute position but also accurately measures the heading angle of the aircraft, ensuring high-precision operations such as construction according to drawings. The attitude sensing unit consists of multiple inertial measurement units mounted on the base 1 and each boom, respectively, for real-time measurement of the pitch, roll, and yaw angles of the base 1 and each boom. In this embodiment, the attitude sensing unit includes a first attitude sensor 52 mounted on the base 1 and a second attitude sensor 16 mounted at the end of the boom. Furthermore, a first tilt sensor 216 is mounted on the first boom 21, and a second tilt sensor 234 is mounted on the third boom 23. Together, they form a distributed attitude measurement network capable of accurately and dynamically measuring the real-time attitude of each boom section, providing critical feedback information for high-precision motion control and vibration suppression.

[0039] The proprioception unit is composed of a joint angle sensor coaxially installed with each rotary joint and a cylinder stroke sensor built into each hydraulic actuator, which is used to measure the real-time joint posture information of each rotary joint. Figure 2 and Figure 3As shown, for the rotary joints, coaxially mounted absolute angle encoders are used, including a first hollow magnetic ring angle encoder 56 for the base rotary joint 6, a second hollow magnetic ring angle encoder 214 for the first arm rotary joint 213, a third hollow magnetic ring angle encoder 223 for the second arm rotary joint 222, and a fourth hollow magnetic ring angle encoder 236 for the third arm rotary joint 235. For the pitch joint driven by the hydraulic cylinder, a high-precision stroke sensor is integrated inside the hydraulic cylinder, such as Figure 4 The second boom cylinder stroke sensor 2215 is shown as being built into the second boom cylinder 221 , and the cylinder stroke sensors (not shown) are built into the first boom cylinder 211 and the third boom cylinder 231 .

[0040] In a preferred embodiment, the structural design of the joint is optimized. An integrated structure is adopted at each rotating joint of the arm assembly 2. This modular design concept integrates all core components related to the joint function into a compact unit. The integrated structure includes: a hydraulic actuator, which is a hydraulic cylinder or a hydraulic motor; an integrated valve block installed at the oil port of the hydraulic actuator; a joint angle sensor or a cylinder stroke sensor in the proprioception unit; an inertial measurement unit in the posture perception unit; and an integrated wiring harness connecting all components in the integrated structure to the control system 3 and an integrated pipeline for hydraulic connection.

[0041] Specifically, Figure 4 Taking the second boom cylinder 221 shown as an example, this integrated structure centers around the second boom cylinder 221. The cylinder's oil inlet and outlet ports are directly connected to the second boom cylinder brake valve block 2213. This integrated valve block compactly houses the second boom cylinder hydraulic servo valve 2214, the second boom cylinder pressure sensor 2211, and the second boom cylinder solenoid switch valve 2212, eliminating the need for extensive external high-pressure oil piping. The cylinder also incorporates a built-in second boom cylinder stroke sensor 2215. The signal and power cables for all these electronic components are integrated into a single wiring harness, connected to the main cable via the second boom cylinder harness port 226. Similarly, for the base rotary joint 6, its integrated structure includes the hydraulic motor 8 as the actuator and the rotational drive brake valve block 85, which integrates the rotational drive hydraulic servo valve 86, the rotational drive pressure sensor 83, and the rotational drive solenoid switch valve 84. Its propulsion sensing unit is the first hollow magnetic ring angle encoder 56, and its posture sensing unit is the nearby first posture sensor 52. The connection is achieved through the rotation drive oil pipe 81 and the rotation drive harness port 82.

[0042] In a further embodiment, the internal architecture of the control system 3 is described in detail. The control system 3 adopts a hierarchical, distributed control architecture, whose core components include a main controller, multiple joint controllers, a constant pressure and constant temperature controller, and a safety controller. The specific functions and information flow of the control architecture can be referred to Figure 5 The control system schematic diagram shown in the figure can be used for further understanding.

[0043] The main controller is electrically connected to the sensing and positioning system and is the top-level decision-making unit of the entire control system 3. Figure 5 As shown, the input end of the main controller is connected to the external obstacle detection system, remote control system, absolute positioning system and end effector posture sensor, etc., for receiving operator instructions, global positioning information and environmental perception data. Its main task is to perform high-level planning and coordination. It receives the three-dimensional point cloud map from the environmental perception unit, the absolute position from the global positioning unit, and the complete posture and joint information from the posture perception unit and the proprioception unit. The core function of the main controller is to fuse multi-source sensor data and obtain an accurate estimate of the state of the robot itself and the environment through algorithms such as Kalman filtering. Then, according to the task instructions input by the operator or the preset work process, and based on the pre-stored multi-body dynamics model, motion planning including vibration prediction and suppression is performed. In Figure 5 Within the functional division of the system, this high-level planning function is implemented by the motion planner module. After planning is complete, the main controller (or its internal motion controller module) generates two sets of key instructions: one is the drive torque sequence, which is sent to each joint controller, instructing each joint on the force or torque output. The drive torque sequence is derived from the motion trajectory data, which contains the corresponding velocity, acceleration, position, and torque sequence in the time dimension. The other is the hydraulic energy supply strategy, which is sent to the constant pressure and constant temperature controller and instructs the entire hydraulic system on how to supply energy and manage heat.

[0044] Multiple joint controllers correspond to each hydraulic actuator one by one and are the middle-level motion execution units. The command input terminals of all joint controllers are connected to the main controller (or Figure 5The joint controllers are connected to the motion controllers in the system and are used to receive motion trajectory data containing the drive torque sequence. Each joint controller is responsible for controlling only one joint. This distributed structure disperses the computing pressure and improves the system's response speed and reliability. The feedback inputs of all joint controllers are connected to the corresponding proprioception units (such as angle sensors and stroke sensors) and sensors in the hydraulic actuator units (such as actuator pressure sensors). Ultimately, they drive the hydraulic servo valves to achieve precise closed-loop pressure control, velocity control, and position control for each arm joint. A special feature is that all joint controllers are equipped with a hydraulic stiffness observer for online analysis of hydraulic stiffness. Hydraulic stiffness is a measure of a joint's ability to resist external disturbances. It is related to factors such as the elastic modulus of the hydraulic oil, the oil chamber volume, and the system pressure, and is a time-varying variable. The hydraulic stiffness observer estimates the current hydraulic stiffness value online by analyzing the pressure and displacement changes of the joints in real time. This stiffness information can be used to adjust the control gain of the joint controller to achieve adaptive control, and can also be fed back to the main controller to optimize motion planning and vibration suppression algorithms, so that the robotic arm can maintain stable and precise performance under different loads and postures, ensuring the accuracy of motion trajectory execution.

[0045] In another embodiment, high-precision pressure sensors are deployed simultaneously at the inlet and outlet of the hydraulic cylinder to collect and calculate the dynamic differential pressure between them in real time. This differential pressure can be accurately converted to the actual load borne by the actuator end, thereby enabling indirect measurement and continuous monitoring of the load. When the monitored load pressure exceeds a preset safety threshold, an alarm is immediately triggered or protective action is initiated, effectively mitigating potential damage to the mechanical structure or hydraulic system due to overload. This system can sensitively capture and interpret complex differential pressure signals caused by multiple factors, including actuator posture changes, acceleration fluctuations during motion, and real-time changes in external loads. The joint controller's embedded algorithm utilizes this high-frequency dynamic feedback data to perform real-time adaptive parameter adjustments, such as dynamically modifying control gains or feedforward compensation models, to offset inherent nonlinearities and external disturbances. This mechanism ensures that the system consistently maintains optimal operating conditions, ultimately achieving precise, responsive, and robust closed-loop control of joint motion trajectory and force output.

[0046] Constant pressure and constant temperature controller and main controller (or Figure 5 It is connected to the motion controller in the main controller and is the underlying energy and environment management unit. Its main responsibility is to receive and execute the hydraulic energy supply strategy issued by the main controller. Figure 5In the functional diagram, the controller is subdivided into two modules: a constant pressure controller and a constant temperature controller. The constant pressure controller receives feedback from the hydraulic pump, pressure sensor, and filter sensor, and controls the speed of the servo motor in each hydraulic power unit in a closed loop, so that the output pressure of the power unit is always stable near the set value, realizing on-demand energy supply. The constant temperature controller actively adjusts the cooling power by controlling the air pump and the hydraulic air cooling system based on the feedback from the oil temperature sensor and the liquid level sensor, and in combination with the predictive thermal management instructions of the main controller, so as to accurately control the oil temperature within a very small fluctuation range, thereby ensuring the thermal stability of the entire system. In addition, if Figure 5 As shown in Figure 1, the control system also includes a dedicated mobile controller. This mobile controller receives chassis movement instructions from the motion controller and, combined with feedback from the attitude sensor and relative orientation system, performs closed-loop control of the mobile chassis to achieve precise movement and positioning of the robotic arm.

[0047] Safety controller in Figure 5 The safety control system is represented in the figure and is a monitoring and protection unit with the highest priority, independent of the main controller and joint controllers. Its core task is to ensure the safety of equipment and personnel. It is used to monitor all sensor signals, including position sensors, pressure sensors, temperature sensors, IMUs, etc. The safety controller sets safety thresholds and change rate limits for each signal. When any such hardware failure or abnormal state is detected, the safety controller immediately bypasses all other controllers and directly sends a locking command to the solenoid switch valves of all hydraulic actuators. The command authority of this locking command is greater than the control commands issued by all other controllers in the control system 3. This means that no matter what kind of motion command is being issued by the main controller or joint controller at the time, the locking command of the safety controller will be enforced, so that the entire robot arm is reliably locked in the current position in the shortest possible time, thereby avoiding the occurrence or escalation of accidents.

[0048] Figure 7 FIG. 1 is a flow chart of a method for controlling a mobile hydraulic mechanical arm in one embodiment. It should be understood that although Figure 7 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 7 At least part of the steps in the above process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but may be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps. Figure 7 As shown, the mobile hydraulic mechanical arm control method disclosed in the present invention specifically includes the following steps: S101. Use the perception and positioning system to obtain the mobile hydraulic manipulator's own state information and the surrounding three-dimensional environment information.

[0049] At the initial stage of the control process, an integrated perception and positioning system comprehensively acquires information about the mobile hydraulic manipulator's state and an accurate three-dimensional model of its operating environment. This process involves more than a simple reading from a single sensor; rather, the main controller deeply integrates information from multiple sources. Specifically, the LiDAR (LiDAR) in the environmental perception unit generates a raw three-dimensional point cloud map of the surroundings. The RTK receiver in the global positioning unit provides the manipulator's centimeter-level absolute position in the world coordinate system. Multiple inertial measurement units in the attitude perception unit measure the pitch, roll, and other attitude angles of the base and each arm in real time. The joint angle sensors and cylinder stroke sensors in the proprioception unit accurately report the current position of each joint. The main controller spatially and temporally aligns and fuses these data from various sensors, with different characteristics and coordinate systems, to construct a unified, accurate, and dynamically updated digital scene, providing a high-confidence decision-making basis for all subsequent planning and control tasks.

[0050] S102. Use the control system to process the self-state information and three-dimensional environmental information, and plan the final motion trajectory of the mobile hydraulic manipulator.

[0051] After acquiring comprehensive state and environmental information, the control system's core planning function is activated to process and calculate this information, ultimately planning a final trajectory that achieves the mission objectives while maintaining high dynamic performance. The core of this step lies in a model-based prediction and optimization process. First, the main controller generates an initial trajectory based on the mission objectives and the integrated environmental information, meeting basic obstacle avoidance and reachability requirements. The main controller then calls upon a pre-stored multibody dynamics model that accurately incorporates dynamic parameters such as mass, moment of inertia, and flexibility of each link in the boom assembly. Using the velocity and acceleration curves of the initial trajectory as input, the dynamic response of the manipulator executing this trajectory is simulated in a virtual environment, enabling prediction of the boom structure's vibrations that may be induced by high-speed motion. If the predicted vibration response exceeds a preset response threshold, the main controller initiates an optimization algorithm that adjusts the velocity and acceleration curves of the initial trajectory to minimize a comprehensive cost function. The goal is to generate the optimal trajectory while satisfying vibration constraints. The trajectory generated after iterative optimization is the final motion trajectory. This trajectory actively suppresses structural vibration from the planning level, ensuring the stability of the robot arm under high-speed movement and the accuracy of end positioning.

[0052] In another implementation, a high-fidelity 3D virtual model of the robotic arm, accurate to the millimeter level, is first constructed based on its real-time state information—a high-fidelity digital twin. Simultaneously, a virtual environment model is generated using 3D environmental information acquired through devices such as LiDAR. The robotic arm's digital twin is then placed within this virtual environment model, creating an interactive simulation scene. Within this virtual space, proactive dynamic and collision simulations can be performed before physical actions are executed. This means the controller can pre-calculate and evaluate multiple candidate motion trajectories, driving the virtual robotic arm with realistic kinematic and dynamic characteristics in simulation, and detecting in real time whether any of its parts will interfere with or collide with any obstacles in the virtual environment. This pre-calculation eliminates all paths with collision risks and selects the optimal trajectory from the remaining safe paths based on optimization criteria such as maximum efficiency, minimum energy consumption, or smoothest motion. This process ultimately outputs the planning results to the underlying motion controller for execution, achieving a fundamental shift from passive obstacle avoidance to active path planning, ensuring precise and efficient, collision-free operation of the robotic arm even in unknown or dynamically changing confined spaces.

[0053] S103. Utilize the control system to generate a hydraulic energy supply strategy according to the final motion trajectory, and instruct multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy.

[0054] Among them, based on the final motion trajectory generated by optimization, the control system will proactively calculate and generate a set of refined hydraulic energy supply strategies, and instruct multiple distributed hydraulic power units in the hydraulic system to strictly follow the strategy to provide precise power for the upcoming movement. The purpose of this step is to transform from a centralized, passive energy supply mode to a distributed, active energy management. The main controller first combines the final motion trajectory and the multi-body dynamics model to inversely solve the driving torque sequence of each rotary joint that changes with time throughout the entire motion process, and then converts the torque demand into the instantaneous power demand curve of each hydraulic power unit through a series of nonlinear mapping models. This power The calculation of the target pressure difference across the actuator can be simplified to The product of the target flow Q is Subsequently, a feedforward energy scheduling strategy is generated based on this power curve, instructing the constant pressure and constant temperature controller to adjust the speed of each servo motor in advance. When a high power demand is predicted, the speed is increased in advance to charge the accumulator for energy storage; during the low power demand phase, the speed is reduced to save energy. During the entire feedforward scheduling, the constant pressure and constant temperature controller also uses the first pressure sensor to perform real-time pressure closed-loop correction to ensure accurate and stable energy supply. This predictive energy scheduling greatly improves the system's energy efficiency and dynamic response capabilities.

[0055] S104. Use the control system to instruct multiple hydraulic actuators in the hydraulic system to drive the boom assembly to move along the final motion trajectory.

[0056] Among them, after the energy supply strategy has been started and the power is ready, the control system finally instructs multiple hydraulic execution units in the hydraulic system to drive the arm assembly to move strictly along the final motion trajectory in a high-precision and high-stability manner. The main controller decomposes the final motion trajectory into target instructions for each joint and sends them to each independent joint controller. Each joint controller first performs preliminary position closed-loop control on the servo valve to which it belongs based on the target instruction and the real-time joint posture feedback from the proprioception unit. In this process, the hydraulic stiffness observer in the joint controller is activated as a core functional module. The observer continuously analyzes the control instructions of the servo valve, the real-time pressure difference measured by the second pressure sensor, and the actual small displacement of the joint, and calculates the equivalent hydraulic stiffness of the current rotary joint online through the dynamic relationship model. , its physical meaning can be understood as the ability to resist deformation, that is , where A is the effective area of ​​the actuator, is the change in joint displacement. When the observed equivalent hydraulic stiffness decreases due to changes in load or oil temperature and falls below a preset threshold, the joint controller automatically adjusts its closed-loop control parameters to accommodate the stiffness change. Simultaneously, it requests the constant pressure and temperature controller to increase the baseline pressure of the power unit corresponding to that joint, thereby achieving active stiffness compensation. This adaptive stiffness control ensures that the robot arm maintains excellent trajectory tracking accuracy under various operating conditions.

[0057] In one embodiment, using a control system to process the self-state information and three-dimensional environment information and plan the final motion trajectory of the mobile hydraulic manipulator includes the following steps: The main controller integrates the multi-source sensor data obtained by the environmental perception unit, global positioning unit, posture perception unit and proprioception unit, and generates an initial motion trajectory according to the preset mission objectives; The main controller calls a pre-stored multi-body dynamics model containing the dynamic parameters of the boom assembly, takes the initial motion trajectory as input, and predicts the vibration response of each boom of the boom assembly when executing the initial motion trajectory; If the predicted vibration response exceeds a preset response threshold, the velocity and acceleration profiles of the initial motion trajectory are adjusted by the main controller using an optimization algorithm to generate a final motion trajectory that actively suppresses structural vibration.

[0058] In this embodiment, at the initial stage of trajectory planning, the main controller deeply fuses the multi-source heterogeneous sensor data from the perception and positioning system to build a unified and accurate spatiotemporal cognitive model, and based on this, generates an initial motion trajectory that meets the basic task requirements. This process first aligns the lidar point cloud of the environmental perception unit, the RTK centimeter-level position of the global positioning unit, the IMU attitude angle of the attitude perception unit, and the joint encoder reading of the proprioception unit in time and space. Subsequently, an optimal estimation algorithm such as the extended Kalman filter (EKF) is used to fuse these noisy measurements from different coordinate systems to estimate the precise state of the robotic arm in real time. This optimal state estimation At each moment k is obtained through a cycle of prediction and update, and its core update step can be expressed as ,in is the Kalman gain, The sensor measurements are obtained. After obtaining a high-confidence state and environment model, a path planning algorithm such as A* or RRT* is invoked to generate a collision-free geometric path in 3D space. This path is finally converted into a time-dependent joint space trajectory, forming an initial motion trajectory with unoptimized dynamic performance.

[0059] After obtaining the initial motion trajectory, the main controller will call a pre-stored multi-body dynamic model that can accurately describe the physical characteristics of the boom assembly to make a forward-looking prediction of the structural vibration that may occur when executing the trajectory. This dynamic model not only includes the rigid body parameters such as mass and inertia of each boom, but also incorporates the flexible characteristics of the boom, that is, its ability to resist bending deformation, through the finite element method or the assumed modal method. The joint angle, angular velocity and angular acceleration sequence corresponding to the initial motion trajectory are used as inputs to this model. The core of the model is a set of differential equations that describe the relationship between the force and motion of the system. Its simplified form is ,in 、 、 represent the inertia, centrifugal force and gravity of the system respectively, and and They represent the equivalent stiffness matrix of the boom and the elastic deformation caused by vibration. By solving this equation, the given driving torque can be accurately calculated. Under the action of elastic deformation, the end of the arm or the key point The effect of this step is that the potential vibration risk is quantitatively grasped before the actual movement occurs, providing an accurate decision-making basis for subsequent active suppression.

[0060] If the predicted vibration response exceeds the preset response threshold to ensure operation accuracy, the main controller will start a trajectory optimization program to generate a final motion trajectory that can actively suppress structural vibration by intelligently adjusting the velocity and acceleration curves of the initial motion trajectory. This process is constructed as a constrained optimization problem, whose goal is to find a trajectory with the best overall performance while meeting the vibration constraints. The trajectory itself consists of a set of parameters Definition, the goal of the optimization algorithm is to find the optimal parameters , so that a certain performance indicator (such as movement time or smoothness) is optimal. The optimization problem can be expressed as: solve , and satisfy the constraints Among them, J is the cost function that measures the quality of the trajectory, such as minimizing the impact during the movement; and w is the function that maps the joint acceleration to the vibration amplitude of the arm end. is the maximum allowable vibration threshold. By employing efficient numerical optimization algorithms such as Sequential Quadratic Programming (SQP), trajectory parameters are iteratively adjusted until the optimal solution is found. This step ultimately results in a smooth motion command with excellent dynamic performance, which guides the robotic arm to complete movements quickly and stably, significantly improving end-position positioning accuracy and reducing fatigue damage to the mechanical structure.

[0061] In one embodiment, generating a hydraulic energy supply strategy based on the final motion trajectory using a control system and instructing multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy includes the following steps: The master controller combines the final motion trajectory with the multi-body dynamics model to calculate the time-varying drive torque sequence of each revolute joint in the process of achieving the final motion trajectory. The driving torque sequence is resolved into a power demand curve for each hydraulic power unit by the main controller; generating a feedforward energy scheduling strategy for the servo motor in each hydraulic power unit according to the power demand curve through the main controller; A feedforward energy scheduling strategy is executed by a constant pressure and constant temperature controller. When the output power of the rotary joint exceeds a preset first power threshold, the speed of the servo motor corresponding to the rotary joint is advanced, and the accumulator is charged with pressure through a quantitative hydraulic pump. When the output power of the rotary joint is lower than a preset second power threshold, the speed of the servo motor corresponding to the rotary joint is reduced, and the first power threshold is greater than the second power threshold. During the execution of the feedforward energy scheduling strategy, the first pressure value of the first pressure sensor in each hydraulic power unit is continuously monitored by the constant pressure and constant temperature controller, and the speed of the servo motor is closed-loop corrected according to the first pressure value.

[0062] In this embodiment, in the first step of energy supply planning, the main controller combines the optimized final motion trajectory with the accurate multi-body dynamics model to perform inverse dynamics calculations to obtain the precise time-varying drive torque sequence that each rotary joint must output to achieve the trajectory. This calculation process is essentially solving the core equations that describe the motion laws of the manipulator. The desired position of each joint included in the final motion trajectory is calculated. , expected speed and expected acceleration As known input, substitute into the multibody dynamics equation: In this equation Represents the inertia matrix, centrifugal force / Coriolis force matrix and gravity matrix that change in real time with the boom posture. By solving this equation, the driving torque vector can be obtained This sequence accurately predicts the inertial forces, linkage coupling forces, and gravity that each joint needs to overcome throughout the entire motion process, providing a precise, physics-based theoretical basis for subsequent energy and motion control.

[0063] After obtaining the joint drive torque sequence, the main controller will perform an analytical process to convert it from the abstract mechanical domain torque to the specific power demand curve required by each independent distributed hydraulic power unit. This analytical process includes multiple mapping steps. First, the drive torque of each joint is converted according to the real-time geometric parameters of the boom assembly. Converted into the thrust or pull required by the corresponding hydraulic actuator Then, based on the effective area A of the hydraulic actuator, this force is converted into the target pressure difference required between the inlet and outlet ports of the actuator. ,Right now At the same time, the required hydraulic oil flow is calculated based on the target movement speed of the actuator Finally, by multiplying the target pressure difference and the target flow rate, we can get the instantaneous power demand curve of the hydraulic power unit over time. The effect of this step is to decompose and quantify the macro joint movement requirements layer by layer into the energy flow that each underlying power source must provide, laying a data foundation for on-demand and efficient energy supply.

[0064] After accurately understanding the future power demand curve, the main controller will generate a forward-looking feedforward energy scheduling strategy for each servo motor in the hydraulic power unit. The core idea of ​​this strategy is to change passive response to active preparation. Its essence is a time-varying speed command curve tailored for the servo motor. . The generation of this command curve is based on the analysis of the power demand curve. The control algorithm will predict the upcoming power peaks and troughs in advance and plan the speed of the servo motor accordingly. For example, before the power peak arrives, the target speed of the motor is increased in advance to drive the quantitative hydraulic pump to pre-charge the accumulator for energy storage; in the foreseeable low-power stage, the target speed is actively lowered to save energy. The effect of implementing this step is to achieve energy peak shaving and valley filling, so that the servo motor and power source do not need to be configured according to the highest peak power, which significantly improves the overall energy utilization efficiency of the system and improves the dynamic response performance of the system.

[0065] The constant pressure and temperature controller is responsible for implementing the feedforward energy scheduling strategy generated by the main controller. Using a threshold-based logic, it actively adjusts the servo motor's speed to achieve intelligent energy storage and release. During execution, it continuously compares future power values ​​on the power demand curve with two preset thresholds: the first and second power thresholds. If the output power is predicted to exceed the higher first power threshold in the near future, the controller preemptively increases the speed of the corresponding servo motor, driving the fixed-displacement hydraulic pump to charge the accumulator at a flow rate higher than the current consumption, converting electrical energy into stored hydraulic energy. Conversely, if the output power is predicted to fall below the lower second power threshold, the servo motor's speed is reduced to an energy-efficient baseline level. At this point, any movement demand is preferentially met by energy released from the accumulator. This strategy enables the hydraulic system to function like a hybrid system, drawing on reserve energy during high demand and resting during low demand, resulting in more efficient and stable operation.

[0066] During the implementation of the feedforward energy scheduling strategy, the constant pressure and constant temperature controller also uses a parallel closed-loop correction circuit to ensure the ultimate accuracy of energy supply, to compensate for errors caused by model inaccuracies and unexpected external disturbances. This circuit continuously monitors the actual pressure reading of the first pressure sensor in each hydraulic power unit and compares it with the desired pressure setpoint corresponding to the feedforward strategy, thereby determining the pressure error. This error is input into a PID (proportional-integral-derivative) controller to generate a real-time compensation adjustment. Ultimately, the actual speed command of the servo motor is the sum of the speed command from the feedforward strategy and the compensation adjustment output by the PID controller. This combined feedforward and feedback control approach leverages the fast response and predictive capabilities of feedforward control with the robustness and high precision of feedback control, ensuring stable, accurate, and reliable power output from the hydraulic system regardless of changing operating conditions.

[0067] In one embodiment, parsing the drive torque sequence into a power demand curve for each hydraulic power unit by the main controller includes the following steps: The main controller obtains real-time joint posture information provided by the joint angle sensor and the cylinder stroke sensor in the proprioception unit, wherein the real-time joint posture information includes relative rotation angle and telescopic length; A nonlinear mapping model is established by the main controller based on the geometric size parameters of the boom assembly, which converts the driving torque of each rotary joint into the required output force of the corresponding hydraulic actuator. The main controller converts the driving torque sequence into the target output force sequence required by each hydraulic actuator in real time through a nonlinear mapping model; The main controller converts the target output force sequence into the target pressure difference sequence required by the inlet and outlet ports of each hydraulic actuator according to the effective action area of ​​each hydraulic actuator; The target pressure difference sequence is combined with the target movement speed of the hydraulic actuator by the main controller to calculate the power demand curve of each hydraulic power unit that varies with time.

[0068] In this embodiment, in the torque-to-power analysis process, the main controller first obtains the current precise joint posture information of the manipulator from the proprioception unit in real time and at high frequency. This information is the basis for subsequent dynamic calculations, specifically including the relative rotation angle provided by the joint angle sensor at each rotary joint and the piston extension length provided by the cylinder stroke sensor at each pitch joint. The controller collects and synchronizes these discrete sensor readings in time, integrating them into a state vector that can fully describe the geometric configuration of the manipulator at any moment. After obtaining the real-time joint posture, the main controller will establish a nonlinear mapping model from the driving torque of each rotary joint to the required output force of its corresponding hydraulic actuator based on the inherent geometric size parameters of the boom assembly. This model mathematically accurately describes the conversion relationship between force and torque. This relationship is not a simple linear proportion, but changes dynamically with the change of the boom posture. For a joint driven by a hydraulic cylinder, the core of the model is a Changing specific components of the transfer function or Jacobian matrix , which reflects the instantaneous changes in the actuator thrust arm. This model was pre-derived through geometric analysis during the robotic arm design phase and solidified in the controller's algorithm library. This step resulted in the creation of a precise mathematical tool capable of accurately translating the virtual torque acting on the joint's rotational center, derived from the upper-level planning, into the actual thrust or torque required by the hydraulic cylinder or motor driving that joint.

[0069] Next, the main controller uses the nonlinear mapping model established in the previous step to convert the previously calculated, time-varying drive torque sequence into the target output force sequence required by each hydraulic actuator in real time. This is a continuous solution process that occurs every millisecond during the execution of the final motion trajectory. The controller extracts the target torque value at a certain time t in the drive torque sequence. , and combined with the real-time joint angles obtained at the same time , calling the mapping model through table lookup or real-time calculation The core calculation can be simplified to solve , thus obtaining the target force that the actuator needs to output at that moment By calculating the entire time series point by point, a complete output force sequence is generated. This step successfully transforms an abstract control target (joint torque) into a specific physical quantity (thrust or pull) that can be directly generated by a physical actuator, paving the way for subsequent hydraulic parameter calculations.

[0070] After obtaining the target output force sequence required by each hydraulic actuator, the main controller will further convert it into the target pressure difference sequence required between the inlet and outlet ports of each hydraulic actuator based on the inherent physical parameters of each actuator. This conversion is based on the basic principle of fluid statics, that is, the force acting on the piston is equal to the fluid pressure multiplied by the effective area of ​​the piston. For a specific hydraulic cylinder, its effective area is a constant that is determined at the time of design and does not change, and is pre-stored in the controller's parameter library. Therefore, the controller only needs to perform a simple division operation, that is, , each force value in the target output force sequence can be converted to a corresponding target pressure differential value. This step completes the key transformation from the mechanical domain to the hydraulic domain, converting the control instructions from force to pressure. Pressure is the core variable that hydraulic systems can directly and precisely control.

[0071] In the final step, the main controller combines the target pressure difference sequence obtained in the previous step with the target movement speed of the hydraulic actuator to calculate the complete power demand curve of each distributed hydraulic power unit that changes over time during the entire movement process. This calculation first requires determining the hydraulic oil flow required to achieve the target movement speed. Based on the target speed of the actuator and the effective area, the instantaneous flow demand can be calculated as Then, by multiplying this flow demand by the target pressure difference at the same moment, we can get the hydraulic power that the power unit needs to output at that moment, that is, By performing this calculation at all time points throughout the entire process, a precise power demand curve is ultimately generated. This curve fully predicts the energy consumption required for future movement and serves as the core data basis for subsequent feedforward energy scheduling and efficient, proactive energy management.

[0072] In one embodiment, using a control system to instruct multiple hydraulic actuators in a hydraulic system to drive the boom assembly to move along a final motion trajectory includes the following steps: The final motion trajectory is sent to each joint controller through the main controller as the target instruction for the position control of the joint controller; For any joint controller, preliminary closed-loop control is performed on the servo valve in the corresponding hydraulic actuator unit through the key controller in combination with the target command and real-time joint posture information; During the preliminary closed-loop control process, the joint controller reads the second pressure value of the corresponding second pressure sensor, and calculates the real-time pressure difference acting on the hydraulic actuator based on the second pressure value; The joint controller uses a built-in hydraulic stiffness observer to analyze the dynamic relationship between the servo valve control command, real-time pressure difference and real-time joint posture information, and calculates the equivalent hydraulic stiffness of the current rotary joint. When the equivalent hydraulic stiffness is lower than the preset hydraulic stiffness threshold, the joint controller adjusts the closed-loop control parameters of the preliminary closed-loop control according to the equivalent hydraulic stiffness, and requests the constant pressure and constant temperature controller to increase the reference pressure of the corresponding hydraulic power unit for stiffness compensation.

[0073] In this embodiment, at the initial stage of drive execution, the optimized final motion trajectory is sent to the independent joint controllers distributed at each rotating joint in the form of digital instructions through the main controller. This process decomposes the macroscopic, coordinated motion planning into microscopic, independent joint tasks. The final motion trajectory itself is a data sequence containing a timestamp, and each time point accurately defines the target position, target speed and even target acceleration that each joint should reach. The main controller distributes these target instructions to the corresponding joint controllers in each control cycle through a high-speed real-time communication bus. The implementation effect of this step is to achieve the decoupling and decentralization of control tasks, and hand over the high-frequency position tracking tasks to dedicated joint controllers for processing, which greatly reduces the computational burden of the main controller and ensures the precise time synchronization of all joint movements, which is a necessary prerequisite for realizing complex multi-axis linkage trajectories.

[0074] For any joint controller that receives a target command, its core task is to combine the target command with the real-time joint posture information from the proprioception unit to perform preliminary closed-loop position control on the servo valve in the hydraulic actuator. This is a continuous comparison and correction process. In each control cycle, the controller sends the target position command from the main controller. The actual position read from the joint angle sensor or cylinder stroke sensor Compare and get the position error This error is then fed into a classic PID (Proportional-Integral-Derivative) controller, which generates a control voltage or current command to drive the servo valve. , and its calculation formula is The effect of implementing this control law is to form a self-correcting negative feedback loop that can automatically compensate for small external disturbances and model errors, forcing the driven joint to accurately track the predetermined motion trajectory.

[0075] While performing initial closed-loop position control, the joint controller simultaneously reads secondary pressure values ​​from two secondary pressure sensors integrated into the hydraulic actuator unit. These sensors measure the real-time operating pressure of the hydraulic actuator (e.g., the rodless and rod-mounted chambers of a cylinder). The controller synchronously acquires these two pressure readings and, through a simple difference operation, calculates the instantaneous pressure differential across the hydraulic actuator piston. This pressure differential directly reflects the actual driving force generated by the actuator to overcome the external load and its own inertia. This step provides a crucial dimension of force perception to the control system, enabling the controller to move beyond a mere blind position tracker and instead perceive the actual load conditions during motion. This provides essential input data for subsequent, more advanced adaptive control and state observation.

[0076] Next, the joint controller uses an internally configured, model-based hydraulic stiffness observer to comprehensively analyze the dynamic relationship between the servo valve control instructions, real-time pressure difference, and real-time joint posture information, and calculates the equivalent hydraulic stiffness of the current rotary joint online. Hydraulic stiffness is a key indicator for measuring the ability of a joint to resist deformation when subjected to external force. The observer uses a simplified dynamic model to identify stiffness parameters in real time. For example, when the servo valve instruction generates a small flow change, it causes the real-time pressure difference (i.e., force) to change. At the same time, the joint posture also produces a slight displacement , then the equivalent hydraulic stiffness It can be estimated through this dynamic response relationship, that is, This observer continuously calculates and outputs a real-time stiffness value. This step enables the control system to self-diagnose, understanding dynamic changes in its mechanical properties in real time, such as changes in system "softness" or "hardness" due to rising oil temperature or changes in posture.

[0077] When the equivalent hydraulic stiffness value calculated by the hydraulic stiffness observer decreases due to changes in operating conditions and falls below a preset hydraulic stiffness threshold to ensure performance, the joint controller immediately activates a dual compensation mechanism. First, at the software level, the controller automatically adjusts its PID closed-loop control parameters based on the current equivalent hydraulic stiffness using a preset gain scheduling table. For example, this adjustment reduces the proportional gain and increases the differential gain to adapt to the softening system and suppress potential oscillations. Second, at the hardware level, the controller immediately sends a request to the constant pressure and constant temperature controller to increase the baseline system pressure of the hydraulic power unit corresponding to the joint. This is because higher system pressure directly and physically increases the stiffness of the hydraulic oil. This coordinated active stiffness compensation between hardware and software ensures that the robot arm maintains high rigidity and high-precision dynamic response characteristics under various loads and environments, greatly enhancing the system's robustness and operational performance.

[0078] In one embodiment, the method further comprises the steps of: The safety controller monitors the readings of all sensors in the perception and positioning system and the hydraulic system, as well as the actual motion trajectory of the mobile hydraulic manipulator in real time and in parallel; If the value of any sensor exceeds the preset danger threshold or the trajectory deviation between the actual motion trajectory and the final motion trajectory exceeds the preset deviation threshold, the safety controller will send a locking command with the highest authority to the solenoid switch valves of all hydraulic actuators on the boom assembly; When the solenoid switch valve receives the locking command, it locks the oil circuits of all hydraulic actuators to freeze the current state of the boom assembly.

[0079] In this embodiment, during the operation of the entire control method, an independent safety controller will monitor all key states of the mobile hydraulic manipulator in real time and in parallel. This monitoring task is multi-dimensional. First, it continuously scans the readings of all sensors in the perception and positioning system and the hydraulic system, including but not limited to pressure, temperature, liquid level, joint angle, cylinder stroke, etc., to ensure that these values ​​are within the preset safe working range. Secondly, it dynamically calculates the deviation between the final motion trajectory command issued by the main controller and the actual motion trajectory fed back by the proprioception unit. This trajectory deviation The calculation can be simplified as follows: at each moment t, the desired position of the end of the manipulator is With actual location The Euclidean distance between The effect of this dual monitoring mechanism is to establish a comprehensive safety line of defense independent of the main control loop, capable of simultaneously capturing failures of local components and loss of control of the overall movement.

[0080] Once the monitoring system detects any predefined dangerous conditions, the safety controller will immediately and unconditionally trigger an emergency braking program with the highest execution authority. This triggering mechanism is based on a set of strict logical judgments. If any of the monitored sensor readings Exceeds its preset danger threshold , or the calculated trajectory deviation Exceeded the preset deviation threshold , a logic "OR" gate will immediately output a trigger signal. The trigger condition R can be expressed as ,in represents the out-of-limit condition of sensor i, An out-of-limit condition represents a trajectory deviation. This means that any single fault is sufficient to trigger a safety response. Once triggered, the safety controller immediately generates a digital lock command and simultaneously broadcasts it to the solenoid valves deployed in all hydraulic actuators on the boom assembly via a dedicated, highest-priority communication link. This command takes precedence over any motion commands issued by the main controller and joint controllers, ensuring absolute priority and mandatory execution of safety measures.

[0081] When all solenoid valves throughout the boom assembly receive a lock command from the safety controller, they instantly perform a physical lock, isolating and locking the oil circuits to all hydraulic actuators, thereby freezing the entire boom assembly's current state within milliseconds. These solenoid valves are fast-response, two-position, two-way, or two-position, three-way valves that, during normal operation, do not interfere with the main oil circuit. Upon receiving the electrical activation signal for the lock command, the valve cores within them instantly switch positions, physically sealing the two working oil chambers of hydraulic actuators (such as cylinders or motors). This seals the hydraulic oil within the chambers. Due to its extremely low compressibility, hydraulic oil forms an immovable, rigid oil column inside and outside the actuator. This action occurs simultaneously at all joints, ultimately instantly and reliably locking the entire robotic arm in the position it was in when the safety command was triggered, effectively preventing collapse, impact, or any other unforeseen, dangerous movement due to loss of control.

[0082] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0083] The one or more embodiments of this application are intended to encompass all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this application should be included in the scope of protection of this application.

Claims

1. A mobile hydraulic mechanical arm, characterized in that: The mobile hydraulic mechanical arm includes an arm assembly, a base, a sensing and positioning system, a hydraulic system and a control system; The base is a movable chassis with an independent driving device; The arm assembly is arranged on a base and is composed of at least two arms connected in series via a rotary joint, and each rotary joint is integrated with a hydraulic actuator for driving; The sensing and positioning system is used to obtain the state information of the robot arm and the three-dimensional environment information around the robot arm; The control system is provided on the boom assembly and is electrically connected to the hydraulic system, the base, and all sensors and hydraulic actuators on the boom assembly via cables, and is used to coordinately control the movement of the mobile hydraulic manipulator arm by combining its own state information and external environment information; The hydraulic system is provided on the boom assembly and includes: a plurality of hydraulic power units corresponding one to each hydraulic actuator of the boom assembly, each hydraulic power unit comprising a servo motor, a quantitative hydraulic pump connected to the servo motor via a bell housing and a coupling, an accumulator installed at the outlet of the quantitative hydraulic pump, and a first pressure sensor; Multiple hydraulic actuator units are integrated on the oil port valve block of the corresponding hydraulic actuator, each hydraulic actuator unit includes a servo valve, a second pressure sensor installed at two working oil ports of the servo valve, and a solenoid switch valve for emergency locking; The hydraulic auxiliary unit includes an oil tank with a liquid level and temperature sensor, a forced refrigeration circulation system consisting of a fan and a compressor driven by a frequency converter, and a filter arranged on the total oil return line.

2. The mobile hydraulic mechanical arm according to claim 1, characterized in that: The perception and positioning system includes: An environmental perception unit, consisting of at least one laser radar installed on the base or the end of the arm assembly, is used to scan and build a three-dimensional point cloud map around the robotic arm in real time; The global positioning unit, consisting of an RTK receiver and receiver antenna mounted on the boom assembly, is used to obtain the absolute position of the robotic arm in the world coordinate system; The attitude sensing unit is composed of multiple inertial measurement units installed on the base and each arm respectively, which is used to measure the pitch, roll and yaw angles of the base and each arm in real time; The proprioception unit consists of a joint angle sensor installed coaxially with each rotary joint and a cylinder stroke sensor built into each hydraulic actuator, and is used to measure the real-time joint posture information of each rotary joint.

3. The mobile hydraulic mechanical arm according to claim 2, characterized in that: Each rotating joint of the arm assembly adopts an integrated structure, and the integrated structure includes: Hydraulic actuator, which is a hydraulic cylinder or hydraulic motor; An integrated valve block installed at the oil port of the hydraulic actuator, wherein the servo valve, the second pressure sensor and the electromagnetic switch valve are all installed on the integrated valve block; A joint angle sensor or a cylinder stroke sensor in the proprioception unit; an inertial measurement unit in the posture sensing unit; As well as, integrated wiring harnesses connecting all components in the integrated structure to the control system and integrated piping for hydraulic connections.

4. The mobile hydraulic mechanical arm according to claim 2, characterized in that: The control system includes: a main controller, electrically connected to the sensing and positioning system, for fusing multi-source sensor data and performing motion planning including vibration prediction and suppression based on a pre-stored multi-body dynamics model, to generate a drive torque sequence and a hydraulic energy supply strategy; Multiple joint controllers, one corresponding to each hydraulic actuator, the command input terminals of all joint controllers are connected to the main controller and are used to receive the drive torque sequence, the feedback input terminals of all joint controllers are connected to the sensors in the corresponding proprioception unit and hydraulic actuator unit, and all joint controllers are equipped with a hydraulic stiffness observer for online analysis of hydraulic stiffness; A constant pressure and temperature controller, connected to the main controller, is used to receive and execute the hydraulic energy supply strategy, close the loop to control the speed of the servo motors in each hydraulic power unit, and adjust the cooling power according to the predictive thermal management instructions of the main controller; The safety controller is used to monitor all sensor signals and send a locking command to the solenoid switch valves of all hydraulic actuators when a hardware failure is detected. The command authority of the locking command is greater than the control commands issued by all other controllers in the control system.

5. A method for controlling a mobile hydraulic mechanical arm, characterized in that: Applied to the mobile hydraulic mechanical arm according to any one of claims 1 to 4, the method comprises the following steps: Use the perception and positioning system to obtain the mobile hydraulic manipulator's own state information and the surrounding three-dimensional environment information; The control system processes the robot's own state information and three-dimensional environmental information, and plans the final motion trajectory of the mobile hydraulic manipulator. Using the control system to generate a hydraulic energy supply strategy according to the final motion trajectory, and instructing multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy; The control system is used to instruct multiple hydraulic execution units in the hydraulic system to drive the boom assembly to move along the final motion trajectory.

6. The mobile hydraulic mechanical arm control method according to claim 5, characterized in that: The process of using the control system to process the self-state information and the three-dimensional environment information and plan the final motion trajectory of the mobile hydraulic manipulator includes the following steps: The main controller integrates the multi-source sensor data obtained by the environmental perception unit, global positioning unit, posture perception unit and proprioception unit, and generates an initial motion trajectory according to the preset mission objectives; The main controller calls a pre-stored multi-body dynamics model containing the dynamic parameters of the boom assembly, takes the initial motion trajectory as input, and predicts the vibration response of each boom of the boom assembly when executing the initial motion trajectory; If the predicted vibration response exceeds a preset response threshold, the velocity and acceleration profiles of the initial motion trajectory are adjusted by the main controller using an optimization algorithm to generate a final motion trajectory that actively suppresses structural vibration.

7. The mobile hydraulic mechanical arm control method according to claim 6, characterized in that: The method of generating a hydraulic energy supply strategy based on the final motion trajectory by using the control system and instructing multiple hydraulic power units in the hydraulic system to provide power for the movement of the boom assembly according to the hydraulic energy supply strategy comprises the following steps: The master controller combines the final motion trajectory with the multi-body dynamics model to calculate the time-varying drive torque sequence of each revolute joint in the process of achieving the final motion trajectory. The driving torque sequence is resolved into a power demand curve for each hydraulic power unit by the main controller; generating a feedforward energy scheduling strategy for the servo motor in each hydraulic power unit according to the power demand curve through the main controller; A feedforward energy scheduling strategy is executed by a constant pressure and constant temperature controller. When the output power of the rotary joint exceeds a preset first power threshold, the speed of the servo motor corresponding to the rotary joint is advanced, and the accumulator is charged with pressure through a quantitative hydraulic pump. When the output power of the rotary joint is lower than a preset second power threshold, the speed of the servo motor corresponding to the rotary joint is reduced, and the first power threshold is greater than the second power threshold. During the execution of the feedforward energy scheduling strategy, the first pressure value of the first pressure sensor in each hydraulic power unit is continuously monitored by the constant pressure and constant temperature controller, and the speed of the servo motor is closed-loop corrected according to the first pressure value.

8. The mobile hydraulic mechanical arm control method according to claim 7, characterized in that: The process of parsing the driving torque sequence into a power demand curve for each hydraulic power unit by the main controller comprises the following steps: The main controller obtains real-time joint posture information provided by the joint angle sensor and the cylinder stroke sensor in the proprioception unit, wherein the real-time joint posture information includes relative rotation angle and telescopic length; A nonlinear mapping model is established by the main controller based on the geometric size parameters of the boom assembly, which converts the driving torque of each rotary joint into the required output force of the corresponding hydraulic actuator. The main controller converts the driving torque sequence into the target output force sequence required by each hydraulic actuator in real time through a nonlinear mapping model; The main controller converts the target output force sequence into the target pressure difference sequence required by the inlet and outlet ports of each hydraulic actuator according to the effective action area of ​​each hydraulic actuator; The target pressure difference sequence is combined with the target movement speed of the hydraulic actuator by the main controller to calculate the power demand curve of each hydraulic power unit that varies with time.

9. The mobile hydraulic mechanical arm control method according to claim 5, characterized in that: The method of using the control system to instruct the multiple hydraulic actuators in the hydraulic system to drive the boom assembly to move along the final motion trajectory includes the following steps: The final motion trajectory is sent to each joint controller through the main controller as the target instruction for the position control of the joint controller; For any joint controller, preliminary closed-loop control is performed on the servo valve in the corresponding hydraulic actuator unit through the key controller in combination with the target command and real-time joint posture information; During the preliminary closed-loop control process, the joint controller reads the second pressure value of the corresponding second pressure sensor, and calculates the real-time pressure difference acting on the hydraulic actuator based on the second pressure value; The joint controller uses a built-in hydraulic stiffness observer to analyze the dynamic relationship between the servo valve control command, real-time pressure difference and real-time joint posture information, and calculates the equivalent hydraulic stiffness of the current rotary joint. When the equivalent hydraulic stiffness is lower than the preset hydraulic stiffness threshold, the joint controller adjusts the closed-loop control parameters of the preliminary closed-loop control according to the equivalent hydraulic stiffness, and requests the constant pressure and constant temperature controller to increase the reference pressure of the corresponding hydraulic power unit for stiffness compensation.

10. The mobile hydraulic mechanical arm control method according to claim 5, characterized in that: The method further comprises the steps of: The safety controller monitors the readings of all sensors in the perception and positioning system and the hydraulic system, as well as the actual motion trajectory of the mobile hydraulic manipulator in real time and in parallel; If the value of any sensor exceeds the preset danger threshold or the trajectory deviation between the actual motion trajectory and the final motion trajectory exceeds the preset deviation threshold, the safety controller will send a locking command with the highest authority to the solenoid switch valves of all hydraulic actuators on the boom assembly; When the solenoid switch valve receives the locking command, it locks the oil circuits of all hydraulic actuators to freeze the current state of the boom assembly.

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