Leveling mechanism for vehicle-mounted photoelectric cabin

Abstract

The invention discloses a leveling mechanism for a vehicle-mounted photoelectric cabin. The leveling mechanism comprises a vehicle-mounted platform arranged in a space rectangular coordinate system, the photoelectric cabin mounted at the front part of the vehicle-mounted platform, a tilt angle sensor arranged at the geometric center position of the photoelectric cabin, four leveling supporting legs arranged on the lower platform surface of the vehicle-mounted platform, and a control box. Unfolding, leveling and withdrawing of the leveling supporting legs are controlled through the control box. In the unfolding stage, the control box sends out an unfolding instruction to control the leveling supporting legs to stretch out and support the ground; when the vehicle-mounted platform is in the leveling stage, the control box collects the inclination angle collected by the inclination angle sensor in real time, and the speed and the direction of the alternating current servo motors of the four leveling supporting legs are jointly controlled through a leveling control strategy, so that the horizontal precision of the vehicle-mounted platform meets the index requirement; and in the withdrawing stage, the operation terminal sends out a withdrawing instruction to control the leveling supporting leg to withdraw and leave the ground. According to the invention, the platform leveling work can be quickly carried out under different ground environment conditions when the vehicle is parked for working.

Description

Technical Field

[0001] The invention relates to the field of vehicle-mounted leveling mechanisms, in particular to a leveling mechanism used for a vehicle-mounted photoelectric cabin. Background Art

[0002] Vehicle-mounted leveling mechanisms are widely used in military and industrial applications. Since the 1960s and 1970s, when hydraulic technology became increasingly mature, most foreign countries began to use hydraulic leveling technology. With the widespread use of sensors, electromechanical leveling technology has also matured and has been used in missile launchers, radar vehicles and many construction machinery.

[0003] Leveling technology is developing rapidly. There are a large number of leveling device manufacturers on the market, but it is difficult to reduce the weight of the device, increase the leveling speed, and improve the leveling accuracy. Summary of the invention

[0004] The purpose of the present invention is to provide a leveling mechanism for a vehicle-mounted photoelectric cabin, comprising a vehicle-mounted platform arranged in a spatial rectangular coordinate system O-XYZ, a photoelectric cabin installed in front of the vehicle-mounted platform, an inclination sensor arranged at the geometric center position of the photoelectric cabin, four leveling support legs arranged at intervals on the lower surface of the vehicle-mounted platform, and a control box connected to the inclination sensor and the leveling support legs.

[0005] The X and Y axes of the spatial rectangular coordinate system O-XYZ are parallel to the horizontal plane, and the Z axis is parallel to the vertical direction.

[0006] The leveling support leg is an output execution unit, and adopts a linear direct-drive pump-controlled electro-hydraulic servo system. Each leveling support leg includes a hydraulic pump-controlled power unit, a flow matching unit and a terminal actuator.

[0007] The hydraulic pump control power unit is a power device for leveling the support legs, including a hydraulic sensor, a hydraulic pump, an AC servo motor connected to the hydraulic pump, and an oil tank connected to the hydraulic pump. The direction and flow output of the hydraulic pump are controlled by adjusting the direction and speed of the AC servo motor, so that the hydraulic pump can generate high-pressure hydraulic oil with different directions and flow rates in forward and reverse rotation.

[0008] The terminal actuator is a linear actuator, which includes a stroke output shaft, a cylinder, a displacement sensor and an oil pressure sensor.

[0009] The stroke output shaft is the output piston rod of the oil cylinder. The displacement sensor is arranged on the stroke output shaft and is located inside the oil cylinder. During operation, the displacement sensor feeds back the movement of the stroke output shaft to the control box in real time to determine whether the leveling support legs are in place.

[0010] The oil pressure sensor is installed between the leveling support leg and the vehicle-mounted platform, and is used for performing virtual leg judgment on the leveling support leg.

[0011] The flow matching unit adopts two flow matching balancing valves, one is a hydraulically controlled one-way valve arranged on the oil inlet side, and the other is a hydraulically controlled one-way valve arranged on the oil return side.

[0012] The control box is an operation terminal, which is used to receive automatic leveling commands, real-time signals from various sensors, and output leveling information executed by the execution unit.

[0013] The use process of the control box controlling the leveling support legs includes three stages, namely, an unfolding stage, a leveling stage and a retracting stage.

[0014] When in the deployment phase, the operating terminal issues a deployment command to control the four leveling legs to extend out to support the ground.

[0015] When in the leveling stage, the control box will use the inclination sensor to collect the inclination angles of the X / Y axis of the current vehicle platform and the X / Y axis of the spatial rectangular coordinate system O-XYZ in real time. After signal calculation and processing, the control box uses the leveling control strategy to jointly control the speed and direction of the AC servo motors of the four leveling support legs to ensure that the horizontal accuracy of the vehicle platform meets the index requirements.

[0016] When in the retraction phase, the operating terminal issues a retraction command to control the four leveling legs to be retracted off the ground, and the retraction phase ends.

[0017] Furthermore, the four leveling support legs are arranged in a rectangular shape below the vehicle-mounted platform.

[0018] The four leveling support legs adjust the position errors between the other three leveling support legs and the highest leveling support leg through a position error leveling algorithm.

[0019] The position error leveling algorithm includes the following steps:

[0020] 1) The leveling support leg opposite to the highest leveling support leg is recorded as leveling support leg 1#, and the other three leveling support legs are recorded as leveling support leg 2#, leveling support leg 3# and leveling support leg 4# in a clockwise direction;

[0021] 2) Establish a spatial rectangular coordinate system O-XYZ with the center point of leveling support leg 1# as the origin, with the X-axis parallel to the longitudinal direction of the vehicle-mounted platform after leveling, the Y-axis parallel to the transverse direction of the vehicle-mounted platform after leveling, and the Z-axis parallel to the vertical direction;

[0022] Then the deviation e of the four leveling support legs that need to be extended is i for:

[0023] e1=β×L a +α×L b

[0024] e2=α×Lb

[0025] e3=0

[0026] e4=β×L a

[0027] Where:

[0028] L a The distance between the center points of the two leveling support legs in the X-axis direction;

[0029] L b The distance between the center points of the two leveling support legs in the Y-axis direction;

[0030] α is the inclination angle between the longitudinal direction of the existing vehicle-mounted platform and the longitudinal direction of the vehicle-mounted platform after leveling, that is, the X-axis;

[0031] β is the inclination angle between the lateral direction of the existing vehicle-mounted platform and the lateral direction of the vehicle-mounted platform after leveling, that is, the Y axis.

[0032] Furthermore, when in the leveling stage, when there is an error between the input command issued by the operating terminal and the signal fed back to the operating terminal by the displacement sensor in the output execution unit, the control box outputs a control signal to the servo driver of the control box to drive the AC servo motor in the output execution unit to work, and drives the hydraulic pump to suck oil from the oil tank through the AC servo motor to form high-pressure hydraulic oil. The high-pressure hydraulic oil is then transmitted to the oil cylinder of the terminal actuator through a pipeline through the pressure port of the hydraulic pump, thereby controlling the piston of the oil cylinder to move in a specified direction.

[0033] Furthermore, when the oil cylinder piston moves to a position close to the specified position and the deviation between the feedback signal of the displacement sensor and the input command approaches zero, the controller outputs a signal to decelerate the AC servo motor until the AC servo motor stops running when the deviation is zero.

[0034] When the cylinder piston moves to the specified position, the hydraulic pump no longer supplies high-pressure hydraulic oil to the cylinder. At this time, under the action of load, the flow matching balance valves on both sides of the hydraulic pump are in a closed state to achieve locking of the hydraulic circuit.

[0035] Furthermore, a 400W AC servo motor is selected as a power device in the hydraulic pump control power unit; the selection of the AC servo motor is based on the 28V DC output interface of the current special heavy-duty vehicle-mounted equipment.

[0036] Furthermore, the hydraulic pump is a 0.5 ml / r quantitative gear pump.

[0037] Furthermore, the oil cylinder uses an asymmetric linear oil cylinder with a piston / rod diameter of 80 / 45 and a stroke of 480 mm.

[0038] Furthermore, a guiding device is provided outside the terminal actuator.

[0039] Furthermore, an oil pressure sensor is provided between the vehicle-mounted platform and the leveling support legs;

[0040] The oil pressure sensor is used to monitor the pressure of the support point of the leveling support leg;

[0041] When in the deployment phase, when the pressure signal of the leveling support leg monitored by the oil pressure sensor received by the controller reaches a preset value, it can be determined that the leveling support leg is actually on the ground, and the deployment phase ends.

[0042] Furthermore, the control box includes a cabinet, a voltage-stabilized power supply, a servo motor driver, an oil pressure sensor signal collector, a human-machine interface, a control circuit board and an operation panel.

[0043] The servo motor driver is a power actuator of the leveling system and is used to drive the AC servo motor.

[0044] The control circuit board is used to complete the tasks of signal processing, model calculation and status display.

[0045] The human-machine interface adopts an embedded serial port screen to display displacement sensor data and information display during and after leveling.

[0046] The operation panel includes several buttons, namely a manual / automatic switching switch, manual lifting control buttons for the left front, left rear, right front and right rear support legs, and manual control buttons for lifting and lowering each support leg and an emergency stop button when the automatic leveling mode fails or the emergency mode is in emergency mode.

[0047] The technical effect of the present invention is unquestionable, and the beneficial effects of the present invention are as follows:

[0048] The present invention uses the application scheme of the direct-drive pump-controlled electro-hydraulic servo system in the leveling system to simplify the structure of the electro-hydraulic leveling platform support system, reduce the energy consumption of the leveling system, improve the system reliability, save the system installation space and reduce the weight of the leveling system. Relying on the advantages of the direct-drive pump-controlled electro-hydraulic servo system such as high control accuracy, fast response speed, compact structure and large power / mass ratio, the leveling system structure is lightweight, the leveling process is fast and automated, and a high-precision leveling effect is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a system composition diagram of the present invention;

[0050] Figure 2 Schematic diagram of leveling support legs;

[0051] Figure 3 Schematic diagram of the position error value of the leveling legs.

[0052] In the figure: 1-vehicle platform; 2-leveling support leg 2; 201-oil pressure sensor; 202-oil cylinder; 203-displacement sensor; 204-stroke output shaft; 205-oil tank; 206-motor; 207-hydraulic sensor; 208-hydraulic pump; 209-flow matching unit; 210-terminal actuator. DETAILED DESCRIPTION

[0053] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0054] Embodiment 1:

[0055] A leveling mechanism for a vehicle-mounted photoelectric cabin comprises a vehicle-mounted platform arranged in a spatial rectangular coordinate system O-XYZ, a photoelectric cabin installed in front of the vehicle-mounted platform, an inclination sensor arranged at the geometric center of the photoelectric cabin, four leveling support legs arranged at intervals on the lower surface of the vehicle-mounted platform, and a control box connected to the inclination sensor and the leveling support legs.

[0056] The X and Y axes of the spatial rectangular coordinate system O-XYZ are parallel to the horizontal plane, wherein the X axis is parallel to the longitudinal direction of the vehicle-mounted platform after leveling, the Y axis is parallel to the transverse direction of the vehicle-mounted platform after leveling, and the Z axis is parallel to the vertical direction.

[0057] The leveling support leg is an output execution unit, and adopts a linear direct-drive pump-controlled electro-hydraulic servo system. Each leveling support leg includes a hydraulic pump-controlled power unit, a flow matching unit and a terminal actuator.

[0058] The hydraulic pump-controlled power unit is a power device for leveling the support legs, including a hydraulic sensor, a hydraulic pump, an AC servo motor connected to the hydraulic pump, and an oil tank connected to the hydraulic pump; the steering direction and flow output of the hydraulic pump are controlled by adjusting the steering direction and speed of the AC servo motor, so that the hydraulic pump can be reversed to generate high-pressure hydraulic oil with different directions and flow rates.

[0059] The hydraulic sensor is installed in the hydraulic pump and is used to detect hydraulic oil in different directions generated by the rotation of the hydraulic pump.

[0060] The terminal actuator is a linear actuator, which includes a stroke output shaft, a cylinder, a displacement sensor and an oil pressure sensor.

[0061] The stroke output shaft is the output piston rod of the oil cylinder. The displacement sensor is arranged on the stroke output shaft and is located inside the oil cylinder. During operation, the displacement sensor feeds back the movement of the stroke output shaft to the control box in real time to determine whether the leveling support legs are in place.

[0062] The oil pressure sensor is installed between the leveling support leg and the vehicle-mounted platform, and is used for performing virtual leg judgment on the leveling support leg.

[0063] The pressure of each supporting point is monitored when the supporting leg is raised. When the value collected by the oil pressure sensor reaches a certain preset value, it indicates that the supporting leg has not produced a false leg phenomenon.

[0064] The flow matching unit adopts two flow matching balancing valves, one is a hydraulically controlled one-way valve arranged on the oil inlet side, and the other is a hydraulically controlled one-way valve arranged on the oil return side.

[0065] The control box is an operation terminal, which is used to receive automatic leveling commands, real-time signals from various sensors, and output leveling information executed by the execution unit.

[0066] The use process of the control box controlling the leveling support legs includes three stages, namely, an unfolding stage, a leveling stage and a retracting stage.

[0067] When in the deployment phase, the operating terminal issues a deployment command to control the four leveling legs to extend out to support the ground.

[0068] When in the leveling stage, the control box will use the inclination sensor to collect the inclination angles of the X / Y axis of the current vehicle platform and the X / Y axis of the spatial rectangular coordinate system O-XYZ in real time. After signal calculation and processing, the control box uses the leveling control strategy to jointly control the speed and direction of the AC servo motors of the four leveling support legs to ensure that the horizontal accuracy of the vehicle platform meets the index requirements.

[0069] When in the retraction phase, the operating terminal issues a retraction command to control the four leveling legs to be retracted off the ground, and the retraction phase ends.

[0070] Embodiment 2:

[0071] The main structure of this embodiment is the same as that of Embodiment 1. Furthermore, the four leveling support legs 2 are arranged in a rectangular shape below the vehicle-mounted platform 1 .

[0072] The four leveling support legs adjust the position errors between the other three leveling support legs and the highest leveling support leg through a position error leveling algorithm.

[0073] The position error leveling algorithm includes the following steps:

[0074] 1) The leveling support leg opposite to the highest leveling support leg is recorded as leveling support leg 1#, and the other three leveling support legs are recorded as leveling support leg 2#, leveling support leg 3# and leveling support leg 4# in a clockwise direction;

[0075] 2) Establish a spatial rectangular coordinate system O-XYZ with the center point of leveling support leg 1# as the origin, with the X-axis parallel to the longitudinal direction of the vehicle-mounted platform after leveling, the Y-axis parallel to the transverse direction of the vehicle-mounted platform after leveling, and the Z-axis parallel to the vertical direction;

[0076] Then the deviation e of the four leveling support legs that need to be extended is i for:

[0077] e1=β×L a +α×L b

[0078] e2=α×L b

[0079] e3=0

[0080] e4=β×L a

[0081] Where:

[0082] L a The distance between the center points of the two leveling support legs in the X-axis direction;

[0083] L b The distance between the center points of the two leveling support legs in the Y-axis direction;

[0084] α is the inclination angle between the longitudinal direction of the existing vehicle-mounted platform and the longitudinal direction of the vehicle-mounted platform after leveling, that is, the X-axis;

[0085] β is the inclination angle between the lateral direction of the existing vehicle-mounted platform and the lateral direction of the vehicle-mounted platform after leveling, that is, the Y axis.

[0086] Embodiment 3:

[0087] The main structure of this embodiment is the same as any one of Embodiments 1 to 2. Furthermore, the leveling support leg includes a hydraulic pump-controlled power unit, a flow matching unit and a terminal actuator.

[0088] The hydraulic pump-controlled power unit is a power device for leveling the support legs, and includes a hydraulic sensor, a hydraulic pump, an AC servo motor connected to the hydraulic pump, and an oil tank connected to the hydraulic pump.

[0089] The terminal actuator is a linear actuator, which includes a stroke output shaft, a cylinder, a displacement sensor and an oil pressure sensor.

[0090] The leveling support leg is installed on the photoelectric cabin frame, and the leveling support leg is fixed to the frame by 4 M14 screws. The various components of the leveling support leg are reasonably designed and arranged, and the various components are fixed by screws and have a good matching structure.

[0091] Embodiment 4:

[0092] The main structure of this embodiment is the same as any one of Embodiments 1 to 3. Furthermore, when in the leveling stage, when there is an error between the input command issued by the operating terminal and the signal fed back to the operating terminal by the displacement sensor in the output execution unit, the control box outputs a control signal to the servo driver of the control box to drive the AC servo motor in the output execution unit to work, and drives the hydraulic pump to suck oil from the oil tank through the AC servo motor to form high-pressure hydraulic oil. The high-pressure hydraulic oil is then transmitted to the oil cylinder of the terminal actuator through a pipeline through the pressure port of the hydraulic pump, thereby controlling the piston of the oil cylinder to move in a specified direction.

[0093] Embodiment 5:

[0094] The main structure of this embodiment is the same as any one of Embodiments 1 to 4. Furthermore, when the cylinder piston moves to a position close to the specified position and the deviation between the feedback signal of the displacement sensor and the input command approaches zero, the controller outputs a signal to decelerate the AC servo motor until the AC servo motor stops running when the deviation is zero.

[0095] When the cylinder piston moves to the specified position, the hydraulic pump no longer supplies high-pressure hydraulic oil to the cylinder. At this time, under the action of load, the flow matching balance valves on both sides of the hydraulic pump are in a closed state to achieve locking of the hydraulic circuit.

[0096] Embodiment 6:

[0097] The main structure of this embodiment is the same as any one of Embodiments 1 to 5. Furthermore, a 400W AC servo motor is selected as a power device in the hydraulic pump control power unit; the selection of the AC servo motor is based on the 28VDC AC output interface currently available in special heavy-duty vehicle-mounted equipment.

[0098] Embodiment 7:

[0099] The main structure of this embodiment is the same as any one of Embodiments 1 to 6. Furthermore, the hydraulic pump is a 0.5 ml / r quantitative gear pump.

[0100] Embodiment 8:

[0101] The main structure of this embodiment is the same as any one of Embodiments 1 to 7. Furthermore, the oil cylinder uses an asymmetric linear oil cylinder with a piston / rod diameter of 80 / 45 and a stroke of 480 mm.

[0102] Embodiment 9:

[0103] The main structure of this embodiment is the same as any one of Embodiments 1 to 8. Furthermore, a guide device is provided outside the terminal actuator.

[0104] Embodiment 10:

[0105] The main structure of this embodiment is the same as any one of Embodiments 1 to 9. Furthermore, an oil pressure sensor is provided between the vehicle-mounted platform and the leveling support legs.

[0106] The oil pressure sensor is used to monitor the pressure of the supporting point of the leveling supporting leg.

[0107] When in the deployment phase, when the pressure signal of the leveling support leg monitored by the oil pressure sensor received by the controller reaches a preset value, it can be determined that the leveling support leg is actually on the ground, and the deployment phase ends.

[0108] Embodiment 11:

[0109] The main structure of this embodiment is the same as any one of Embodiments 1 to 10. Furthermore, the control box includes a cabinet, a voltage-stabilized power supply, a servo motor driver, an oil pressure sensor signal collector, a human-machine interface, a control circuit board and an operation panel.

[0110] The servo motor driver is a power actuator of the leveling system and is used to drive the AC servo motor.

[0111] The control circuit board is used to complete the tasks of signal processing, model calculation and status display.

[0112] The human-machine interface adopts an embedded serial port screen to display displacement sensor data and information display during and after leveling.

[0113] The operation panel includes several buttons, namely a manual / automatic switching switch, manual lifting control buttons for the left front, left rear, right front and right rear support legs, and manual control buttons for lifting and lowering each support leg and an emergency stop button when the automatic leveling mode fails or the emergency mode is in emergency mode.

[0114] Embodiment 12:

[0115] The main structure of this embodiment is the same as any one of Embodiments 1 to 11. Furthermore, the product composition, function and basic principle of this application are as follows:

[0116] Product composition

[0117] The electro-hydraulic leveling system of the photoelectric platform is mainly composed of 4 photoelectric leveling support legs, a control box, an inclination sensor and cables. The system consists of Figure 1 shown.

[0118] The main components / assemblies of the leveling system have the following functions:

[0119] Photoelectric leveling support legs: It is the actuator of the photoelectric platform leveling system, which consists of a hydraulic pump-controlled power unit, a flow matching unit and a terminal actuator, etc. It has a direct-drive pump-controlled cylinder electro-hydraulic servo drive integrated split compact structure design. The terminal actuator is equipped with an oil pressure sensor to detect the force of the support legs and solve the problem of the support legs "not touching the ground".

[0120] Tilt sensor: A three-axis tilt sensor is selected for the photoelectric platform leveling system. It can accurately measure the angle between the vehicle-mounted platform and the X-axis and Y-axis of the horizontal plane, and provide a horizontal angle signal for the automatic leveling of the control system. The three-axis tilt sensor is installed at the center of the platform.

[0121] Control box: system operation terminal, composed of servo motor driver, oil pressure sensor signal collector, serial port display screen, control circuit board and operation panel, etc. The controller receives the automatic leveling command and real-time signals of each sensor from the display and control terminal, enters the leveling program through the control strategy, and feeds back the leveling information to the display and control terminal in real time. The console has automatic, manual and emergency control functions.

[0122] Product Features

[0123] The photoelectric leveling system can quickly level the platform when the vehicle is parked in different ground conditions (sand, gravel, land slope, etc.). It mainly levels the photoelectric platform after the vehicle is stopped.

[0124] How it works

[0125] The photoelectric platform leveling system of the present invention is an electro-hydraulic servo drive control leveling system, and the entire control process is divided into three stages.

[0126] Deployment stage: The operation terminal issues a deployment command to control the four leveling legs to extend and support the ground. The controller receives the pressure signal from the oil pressure sensor of the support legs and determines that they have actually touched the ground, and the deployment stage ends.

[0127] Leveling stage: After the controller issues a leveling command, the X / Y axis inclination angle of the inclination sensor is collected in real time. After signal calculation and processing, the servo motor speed and direction of the four supporting legs are jointly controlled through the leveling control strategy to ensure that the horizontal accuracy of the platform meets the index requirements;

[0128] Retraction phase: The operating terminal issues a retraction command to control the four leveling legs to retract and leave the ground, and the retraction phase ends.

[0129] Embodiment 13:

[0130] The main structure of this embodiment is the same as any one of Embodiments 1 to 12. Furthermore, the structural design of this application is:

[0131] The hydraulic power output unit of the photoelectric leveling device uses four linear direct-drive pump-controlled electro-hydraulic servo systems as the support system (support legs) of the leveling system. Each support leg has a split and compact structure design, consisting of a hydraulic pump power unit, a flow matching unit, and a terminal actuator. By applying the direct-drive pump-controlled electro-hydraulic servo system to the leveling system, combined with the advantages of the direct-drive pump-controlled electro-hydraulic servo system such as high control accuracy, fast response speed, compact structure, and large power / mass ratio, the leveling system structure is lightweight, the leveling process is fast and automated, and the leveling effect is high-precision. The photoelectric leveling system support legs are as follows: Figure 2 shown.

[0132] Working principle: When the controller detects that there is a deviation between the input command issued by the operation terminal and the feedback signal of the output actuator displacement sensor, the controller outputs a control signal to the servo driver to drive the servo motor to work, driving the quantitative gear pump to rotate. The pressure oil provided by the gear pump passes through the hydraulic control one-way valve on the oil inlet side. Since the pump oil side belongs to the high-pressure side, the oil enters the working chamber. At the same time, the hydraulic control one-way valve on the return oil side is opened due to the control pressure on the high-pressure side, and the gear pump and the return oil side hydraulic circuit are established, so that the piston moves in the specified direction. When the piston moves to a position close to the specified position, the deviation between the sensor feedback signal and the input command approaches zero, and the controller outputs a signal to decelerate the motor until the motor stops running when the comparison deviation is zero. The gear pump no longer provides pressure oil. Under the action of the load, the hydraulic control one-way valves on both sides are in a closed state, realizing the locking of the hydraulic circuit, which can ensure that the hydraulic cylinder does not move under load or external disturbances.

[0133] (1) Support leg hydraulic actuator

[0134] The terminal actuator of the leveling support leg is designed as a linear actuator, which consists of a stroke output shaft, a cylinder, and a displacement feedback sensor. Considering the actual installation method and usage, the terminal actuator adopts an asymmetric linear cylinder, and the internally immersed magnetic displacement sensor is used to feedback the position of the servo cylinder to realize the position control and synchronous control of the actuator.

[0135] The support leg hydraulic actuator outputs power to the outside through the high-pressure hydraulic oil acting on the piston. In the present invention, the power is output in the form of linear displacement and force. Considering that the hydraulic actuator may be subjected to lateral force (or radial force), the lateral force will have an adverse effect on the force condition and sealing of the output rod of the hydraulic actuator. Long-term operation with lateral force will cause leakage and deformation of the output rod. Therefore, a guide device is added to the outside of the hydraulic actuator to reduce the adverse effect of the lateral force on the hydraulic actuator.

[0136] In the electro-hydraulic leveling system, a 400W AC servo motor is used as the power device, and a hydraulic cylinder with a stroke piston / rod diameter of 80 / 45 and a stroke of 480mm is used as the hydraulic actuator. The minimum length of the hydraulic cylinder after contraction is 800mm, the maximum speed can reach 5mm / s, the maximum thrust is 10 tons, and the displacement sensor and oil pressure sensor are built-in. The built-in displacement sensor can be used to sense the current position status information of the support leg, and the oil pressure sensor can be used to judge the virtual leg of the support leg, thereby improving the stability and safety of the leveling system.

[0137] (2) Support leg power unit

[0138] The support leg power output unit is the power device of the support leg, which is mainly composed of an AC servo motor, a hydraulic pump, a flow matching valve, a hydraulic sensor and a cylinder. The selection of the AC servo motor is based on the fact that most special heavy-duty vehicle-mounted equipment currently has a 28V DC AC output interface. At the same time, compared with AC servo drive actuators, AC servo motors have the advantages of high efficiency and a large power / weight ratio.

[0139] In the electro-hydraulic leveling system, a 400W AC servo motor is selected as the power device, and the pump is selected as 0.5ml / r. When the motor is 3000r / min, the flow rate can reach 1.5L / min, and the hydraulic cylinder runs at a speed of 5mm / s.

[0140] Working principle: The hydraulic pump power unit is the driving power source for the leveling support leg. The working principle is to use an AC servo motor to control the pump oil displacement, and to control the direction and flow output of the quantitative pump by adjusting the direction and speed of the servo motor. The servo motor drives the hydraulic pump to generate high-pressure hydraulic oil in different directions. The high-pressure hydraulic oil enters the volume of the hydraulic actuator through the logic control oil circuit of the flow matching valve to achieve the output of force and displacement. The structure of the support leg power unit is as follows: Figure 3 shown.

[0141] Embodiment 14:

[0142] The main structure of this embodiment is the same as any one of Embodiments 1 to 13. Furthermore, the hardware design of this application is as follows:

[0143] The hardware system of the photoelectric leveling system is the vehicle-mounted platform measurement and control system, which mainly includes the control cabinet, main control circuit board, inclination sensor, displacement sensor, oil pressure sensor and AC servo drive system, etc. The control cabinet is the terminal equipment for operators to operate the leveling system; the main control circuit board is the nerve center of the vehicle-mounted platform measurement and control system, which completes signal processing, model calculation and status display, etc.; since the photoelectric cabin is installed at the front of the vehicle-mounted platform, the inclination sensor is installed at the geometric center of the photoelectric cabin to detect the inclination of the photoelectric cabin in the X-axis and Y-axis directions; the position sensor is built into the output rod of the support leg hydraulic actuator to detect the real-time position of each support leg; the oil pressure sensor detects the force condition of the four support legs to solve the "false grounding" problem; the AC servo drive system is the power actuator of the leveling system.

[0144] (1) Control box design

[0145] The console is the terminal equipment for operators to operate the leveling system. It is mainly composed of a cabinet, a voltage-stabilized power supply, a human-machine interface touch screen, a main control circuit board, an AC servo driver, etc. It is the control core of the leveling device and is mainly used to control the four leveling support legs of the leveling platform to carry out the deployment, leveling and retraction of the vehicle-mounted platform. The standard chassis is the operating terminal of the vehicle-mounted leveling system, and all operations are performed on the control cabinet panel and the human-machine interface.

[0146] On the left side of the control box is the status monitoring display interface, which completes the automatic leveling human-computer interaction of the leveling system; the buttons on the right side of the panel are the manual / automatic switch, and the manual lifting control buttons of the left front, left rear, right front, and right rear support legs, which can meet the needs of manually controlling the lifting and lowering of each support leg when the automatic leveling mode fails or in emergency mode; an emergency stop button is installed to ensure one-click system power-off in an emergency.

[0147] (2) Status monitoring interface display

[0148] The human-machine interface uses an embedded serial port screen to display the status of the leveling system, mainly displaying information such as displacement sensor data, leveling process and leveling completion.

[0149] (3) Tilt sensor

[0150] The inclination sensor is the key core component of the leveling device. The accuracy and working reliability of the sensor are the basis for ensuring that the leveling accuracy of the photoelectric cabin can meet the technical index requirements. From solid geometry, we know that if two intersecting straight lines on a surface are parallel to a plane, then the surface where these two straight lines are located is parallel to the plane. Based on this basic law, the key to the leveling system of the vehicle-mounted platform is that the inclination sensor feedbacks the actual tilt angle of the platform and makes corresponding adjustments based on this data.

[0151] During the leveling process, the inclination sensor feedback value is used as the basis for judging the leveling of the platform, and the position of the highest and lowest points of the platform is determined according to the positive and negative relationship of the feedback inclination value. The displacement deviation between each support point is calculated based on the functional relationship between the inclination value and the distance between the legs and the displacement feedback of each leg. The corresponding servo motor control signal is given to control the corresponding leg to approach the center point at different extension speeds until the platform inclination meets the accuracy range and the leveling is completed.

[0152] (4) Displacement sensor

[0153] The displacement sensor is the key core component of the support leg hydraulic actuator. The accuracy and working reliability of the sensor are the prerequisites for ensuring that the leveling accuracy of the leveling device can meet the technical index requirements.

[0154] (5) Oil pressure sensor

[0155] The oil pressure sensor detects the stress state of the support leg to solve the virtual leg problem of the leveling device. The leveling system of the present invention adopts a four-point rigid support structure. In plane geometry, three points determine a plane, so one of the legs in the system will be used as an auxiliary support, which will cause the "virtual leg" problem. When the "virtual leg" problem occurs, the leveling system is in an unstable state, and the horizontal inclination angle jumps up and down, affecting the control accuracy of the leveling system. Therefore, during the leveling process, the "virtual leg" phenomenon is not allowed to occur.

[0156] The oil pressure sensor is used to determine the "empty leg" phenomenon of each executing leg. In order to solve the "empty leg" phenomenon of the supporting leg, the oil pressure sensor is installed between the executing supporting leg and the platform. It is responsible for monitoring the pressure of each supporting point when the executing supporting leg rises. When the value collected by the oil pressure sensor reaches a certain preset value, it indicates that the supporting leg has a load on the ground.

[0157] (6) AC servo drive system

[0158] The AC servo drive is the controller of the servo motor. This project uses the position control mode to accurately control the running position of the servo motor with PWM pulse width modulation. It has multiple monitoring functions, including 14 real-time monitoring items such as current, motor speed, rotor position, and input pulse number. It also has protection modes such as overcurrent, overvoltage, overload, and encoder failure. Once the AC servo motor is blocked, resulting in overcurrent or overload, the servo drive can enter the alarm mode to protect the motor.

[0159] Embodiment 15:

[0160] The main structure of this embodiment is the same as any one of Embodiments 1 to 14. Furthermore, the software design of this application is:

[0161] The vehicle-mounted platform leveling system software solution has two software configuration items, including the host computer QT software and the control board embedded leveling control software, both of which are controlled by independent software to complete the vehicle's automatic leveling and automatic retraction tasks. When an abnormal situation occurs during the execution process, a status signal is given. If necessary, the reset button can be pressed to exit the program and switch the control system to manual state.

[0162] (1) Host computer software

[0163] The host computer interface uses QT software for interface configuration modeling, and the human-computer interaction interface is specially designed for users, so that the automatic leveling system can display the system working status in real time and set and switch the system functions according to work needs. The operation display panel can be used to perform corresponding leveling operations through the instruments and meters on the operation display interface during the system's automatic working process or manual operation. The host computer interface and the embedded control circuit board communicate through RS485 for data exchange, complete the parameter setting and command output of the leveling system, and collect the status signal of the control circuit board and real-time parameter display.

[0164] (2) Embedded control software

[0165] The embedded control software is the core of the entire vehicle-mounted platform leveling system. It is embedded software installed in the TMS32F407 integrated chip. The main functions of the software include receiving the operation commands of the upper computer human-machine interface, collecting the inclination data of the platform sensor and processing the data, and controlling the lifting and lowering of the platform support legs to achieve the leveling purpose. The software is mainly composed of the following 7 functional modules: initialization module, power-on self-test module, expansion module, leveling module, secondary leveling module, retraction module and manual / automatic function module.

[0166] Embodiment 16:

[0167] The main structure of this embodiment is the same as any one of Embodiments 1 to 15. Furthermore, the key points of this application are:

[0168] (1) Design of direct-drive pump-controlled cylinder electro-hydraulic servo drive actuator

[0169] Due to the limitation of volume and mass, the leveling system has a large single leg load capacity, which is one of the key points of the whole leveling system. The support leg drive type of this project is a direct-drive pump-controlled cylinder electro-hydraulic servo drive system, which has the characteristics of large stroke, strong load capacity, high intelligence, high sensitivity, compact structure and fireproof compared with traditional pneumatic actuators and electric actuators.

[0170] The core key technologies of the direct-drive pump-controlled cylinder electro-hydraulic servo drive system mainly include two aspects:

[0171] a) Design of power unit based on pump-controlled cylinder

[0172] The power unit adopts electro-hydraulic direct drive technology based on pump-controlled cylinders, which is the two core key indicators for achieving efficient and high-precision position and speed control. The motion angular displacement and angular velocity (or linear displacement and speed) of its terminal actuator are completely controlled by the hydraulic oil flow output by the power unit. The position and speed of the hydraulic cylinder are controlled by volume speed regulation, which solves the problem of precise flow control of the power unit in a wide range, and has the advantages of energy saving, high efficiency, and fast response speed. The entire power unit can achieve stepless adjustment from zero to maximum flow, which can not only achieve high-precision output flow control of the power unit, but also ensure high volumetric efficiency and mechanical efficiency of the hydraulic pump, thereby ensuring that the power unit has high overall energy efficiency. At the same time, the structure of the pump-controlled cylinder is easy to design into a closed system, which is convenient for mobile layout and control.

[0173] b) Flow matching unit design

[0174] The vehicle-mounted leveling system has repeated leveling processes during the automatic leveling process. After the leveling action is completed, the legs are subjected to heavy loads for a long time when the power is off, and the leveling accuracy must be locked. Therefore, solving the problem of the stability of position control and speed control of the leveling platform of the controlled object under load is one of the key technologies of the entire system.

[0175] Compared with the balancing valves commonly used in traditional pump-controlled cylinder systems, flow matching balancing valves are used in pairs and also have a two-way locking function, which can achieve smooth operation and reliable locking of the hydraulic system under various load conditions, and can still control the volume of the valve body in situations with high flow matching ratios. The application of the flow matching unit can always keep the pressure difference between the oil chambers of the terminal actuators and the load effects balanced with each other during the process of the hydraulic oil flow constantly changing, especially at the two special working points of starting and stopping, which can also ensure this balance. The control accuracy of the load when starting and stopping is not affected by the negative load, and it can also ensure that the terminal actuator can be fine-moved at a very small distance, meeting the system's high efficiency, high load capacity, and high precision requirements.

[0176] (2) Kinematic characteristics analysis of four-point support mechanism

[0177] When designing a leveling system, the main issues that need to be considered include: how to control the movement of the four support points during the leveling process, how to determine whether the movement of the legs at each support point meets the requirements, how to solve the "virtual leg" problem, and how to reasonably select and improve the leveling control strategy and control method. To solve the above problems, it is key to model the kinematic characteristics of the four-point support mechanism of the leveling system during the leveling process, conduct mathematical modeling, simulation verification, and technical analysis.

[0178] In the design of the present invention, a study on the kinematic characteristics of the four-point support mechanism will be carried out, the position and posture of the four-point support mechanism will be analyzed, a kinematic model of the four-point support mechanism will be established, and the motion simulation of the four-point leveling model will be performed to optimize the system structure and determine a leveling control strategy that combines the highest point stationary "chasing" position error and angle error.

[0179] Position error leveling algorithm: The key to the software algorithm of the position error leveling method is that the vehicle-mounted platform calculates the position error between the other three legs and the highest leg after the pre-support state.

[0180] The outrigger position error value algorithm is as follows:

[0181] The horizontal coordinate system is established with the center point of the lower left support leg of the platform as the origin. The horizontal axis is the X axis and the vertical axis is the Y axis. The distance between the center points of the two support legs in the X axis direction is calculated as L a , the distance between the center points of the two supporting legs in the Y-axis direction is counted as L b . Assume that the inclination angle in the X-axis direction is α, the inclination angle in the Y-axis direction is β, and 3 is the highest point. Assume that e i is the deviation amount that the four legs need to be extended, and the calculated value is as follows.

[0182] e1=β×L a +α×L b

[0183] e2=α×L b

[0184] e3=0

[0185] e4=β×L a

[0186] (3) Design of measurement and control system of electro-hydraulic leveling system

[0187] The leveling system is a high-tech product that integrates mechanics, electricity and fluids. Its good performance depends not only on the good performance of the servo cylinder itself, but also on the design of the corresponding measurement and control system. The leveling system involves multi-point coordinated control. In order to achieve a good leveling effect, the movement position and state of each support point during the leveling process must be detected and controlled in real time. It is necessary to select the sensor device, determine the reasonable control method, and optimize the automatic leveling program.

[0188] The leveling system is a closed-loop control system with two related inputs and four related outputs. It is a closed-loop control system with multiple inputs and multiple outputs, and the classical control theory can no longer solve the problem. In order to achieve automatic leveling of the project, the structure is first orthogonalized, that is, the X and Y directions of the three-axis tilt sensor are designed as two orthogonal components, and the four legs are arranged in a rectangle; and the three-axis tilt sensor is placed in a posture parallel to the line connecting the two adjacent points of the legs. Then, through speed regulation and stroke synchronization technology, the characteristics of the two legs on the same component are basically the same, so that the original multi-input and multi-output system is transformed into four single independent systems. In order to detect the displacement and pressure of the legs, the test bench also installed displacement sensors and oil pressure sensors on the four legs.

[0189] The leveling control system adopts direct digital control. The three-axis inclination sensor in the center of the platform can monitor and feedback the platform inclination changes in real time. Each leg is equipped with a displacement sensor to detect the displacement change of the leg, and the oil pressure sensor is used to detect the force of the leg. The leveling control law is implemented by software, which is easy to adopt complex control algorithms. The designed controller has the advantages of flexible parameter changes, strong anti-interference ability, and easy system debugging and maintenance.

Claims

1. A leveling mechanism for a vehicle-mounted photovoltaic cabin, characterized in that: It includes a vehicle-mounted platform arranged in a spatial rectangular coordinate system O-XYZ, a photoelectric cabin installed at the front of the vehicle-mounted platform, an inclination sensor arranged at the geometric center of the photoelectric cabin, four leveling support legs arranged at intervals on the lower surface of the vehicle-mounted platform, and a control box connected to the inclination sensor and the leveling support legs; The X and Y axes of the spatial rectangular coordinate system O-XYZ are parallel to the horizontal plane, and the Z axis is parallel to the vertical direction; The leveling support leg is an output execution unit, adopting a linear direct-drive pump-controlled electro-hydraulic servo system, and each leveling support leg includes a hydraulic pump-controlled power unit, a flow matching unit and a terminal actuator; The hydraulic pump control power unit is a power device for leveling the support legs, including a hydraulic sensor, a hydraulic pump, an AC servo motor connected to the hydraulic pump, and an oil tank connected to the hydraulic pump; the steering direction and flow output of the hydraulic pump are controlled by adjusting the steering direction and speed of the AC servo motor, so that the hydraulic pump can generate high-pressure hydraulic oil with different directions and flow rates in forward and reverse rotation; The terminal actuator is a linear actuator, including a stroke output shaft, a cylinder, a displacement sensor and an oil pressure sensor; The stroke output shaft is the output piston rod of the oil cylinder. The displacement sensor is arranged on the stroke output shaft and is located inside the oil cylinder. During operation, the displacement sensor feeds back the movement of the stroke output shaft to the control box in real time to determine whether the leveling support legs are in place. The oil pressure sensor is installed between the leveling support leg and the vehicle-mounted platform, and is used to determine whether the leveling support leg is in a virtual state; The flow matching unit adopts two flow matching balancing valves, one is a hydraulically controlled one-way valve arranged on the oil inlet side, and the other is a hydraulically controlled one-way valve arranged on the oil return side; The control box is an operation terminal, which is used to receive automatic leveling commands, real-time signals from various sensors, and output leveling information executed by the execution unit; The use process of the control box controlling the leveling support legs includes three stages, namely, an unfolding stage, a leveling stage and a retracting stage. When in the deployment stage, the operating terminal issues a deployment command to control the four leveling legs to extend out to support the ground; when in the leveling stage, the control box will use the inclination sensor to collect the inclination angles of the X / Y axis of the current vehicle platform and the X / Y axis of the spatial rectangular coordinate system O-XYZ in real time. After signal calculation and processing, the speed and direction of the AC servo motors of the four leveling support legs are jointly controlled through the leveling control strategy to ensure that the horizontal accuracy of the vehicle platform meets the index requirements; when in the retraction stage, the operating terminal issues a retraction command to control the four leveling legs to retract and leave the ground, and the retraction stage ends.

2. A leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: The four leveling support legs 2 are arranged in a rectangular shape below the vehicle-mounted platform 1; The four leveling support legs 2 adjust the position errors between the other three leveling support legs and the highest leveling support leg through a position error leveling algorithm; The position error leveling algorithm includes the following steps: 1) The leveling support leg opposite to the highest leveling support leg is recorded as leveling support leg 1#, and the other three leveling support legs are recorded as leveling support leg 2#, leveling support leg 3# and leveling support leg 4# in a clockwise direction; 2) Establish a spatial rectangular coordinate system O-XYZ with the center point of leveling support leg 1# as the origin, with the X-axis parallel to the longitudinal direction of the vehicle-mounted platform after leveling, the Y-axis parallel to the transverse direction of the vehicle-mounted platform after leveling, and the Z-axis parallel to the vertical direction; Then the deviation e of the four leveling support legs that need to be extended is i for: e1=β×L a +α×L b <h2 style=";text-align:left;direction:ltr">e2 = α×L<h2 style=";text-align:left;direction:ltr"> b e3＝0 e4=β×L a Where: L a The distance between the center points of the two leveling support legs in the X-axis direction; L b The distance between the center points of the two leveling support legs in the Y-axis direction; α is the inclination angle between the longitudinal direction of the existing vehicle-mounted platform and the longitudinal direction of the vehicle-mounted platform after leveling, that is, the X-axis; β is the inclination angle between the lateral direction of the existing vehicle-mounted platform and the lateral direction of the vehicle-mounted platform after leveling, that is, the Y axis.

3. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: When in the leveling stage, when there is an error between the input command issued by the operating terminal and the signal fed back to the operating terminal by the displacement sensor in the output execution unit, the control box outputs a control signal to the servo driver of the control box to drive the AC servo motor in the output execution unit to work, thereby driving the hydraulic pump to work. The pressure oil provided by the hydraulic pump passes through the hydraulically controlled one-way valve on the oil inlet side. Since the oil pressure on the oil inlet side of the hydraulic pump is higher, the oil enters the working chamber. At the same time, the hydraulically controlled one-way valve on the return oil side is opened due to the pressure on the high-pressure side, forming a hydraulic pump and a hydraulic circuit on the return oil side, thereby controlling the stroke output axis to move in the specified direction.

4. A leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 3, characterized in that: When the cylinder piston moves to a position close to the specified position and the deviation between the feedback signal of the displacement sensor and the input command approaches zero, the controller outputs a signal to decelerate the AC servo motor until the deviation reaches zero and the AC servo motor stops running. When the cylinder piston moves to the specified position, the hydraulic pump no longer supplies high-pressure hydraulic oil to the cylinder. At this time, under the action of load, the flow matching balance valves on both sides of the hydraulic pump are in a closed state to achieve locking of the hydraulic circuit.

5. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: A 400W AC servo motor is selected as a power device in the hydraulic pump control power unit; the selection of the AC servo motor is based on the 28V DC output interface of the current special heavy-duty vehicle-mounted equipment.

6. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: The hydraulic pump is a 0.5 ml / r quantitative gear pump.

7. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: The oil cylinder is an asymmetric linear oil cylinder with a piston / rod diameter of 80 / 45 and a stroke of 480 mm.

8. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: A guiding device is arranged outside the terminal actuator.

9. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: An oil pressure sensor is provided between the vehicle-mounted platform and the leveling support legs; The oil pressure sensor is used to monitor the pressure of the support point of the leveling support leg; When in the deployment phase, when the pressure signal of the leveling support leg monitored by the oil pressure sensor received by the controller reaches a preset value, it can be determined that the leveling support leg is actually on the ground, and the deployment phase ends.

10. The leveling mechanism for a vehicle-mounted photovoltaic cabin according to claim 1, characterized in that: The control box includes a cabinet, a voltage-stabilized power supply, a servo motor driver, an oil pressure sensor signal collector, a human-machine interface, a control circuit board and an operation panel; The servo motor driver is a power actuator of the leveling system, which is used to drive the AC servo motor; The control circuit board is used to complete the tasks of signal processing, model calculation and status display; The human-machine interface adopts an embedded serial port screen to display displacement sensor data and information display during and after leveling. The operation panel includes several buttons, namely a manual / automatic switching switch, manual lifting control buttons for the left front, left rear, right front and right rear support legs, and manual control buttons for lifting and lowering each support leg and an emergency stop button when the automatic leveling mode fails or the emergency mode is in emergency mode.

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