WO2015109975A1

WO2015109975A1 - Concrete pump truck and boom control method

Info

Publication number: WO2015109975A1
Application number: PCT/CN2015/070973
Authority: WO
Inventors: 唐修俊; 谭凌群; 武利冲; 蒲东亮
Original assignee: 三一汽车制造有限公司
Priority date: 2014-01-26
Filing date: 2015-01-19
Publication date: 2015-07-30
Also published as: CN103806666B; CN103806666A

Abstract

Disclosed are a boom control method and a concrete pump truck, wherein the control method comprises acquiring an actuating signal of a remote controller, a current state angle signal of each boom section of a boom, and a rotation angle signal of the boom in real time; and planning the movement of the tail end of the boom. The method further comprises a prediction control, in which, according to the target moving direction of the tail end of the boom, the coordinate values of the tail end point of the boom are calculated in real time, if the tail end point of the boom deviates from the target moving direction, the tail end of the boom is arranged according to a secondary plan, and a next target point is output by means of the secondary plan. In this method, the tail end of the boom is arranged according to a secondary plan in the condition that the tail end of the boom deviates from the target moving direction, the probability that the boom stretches and contracts repeatedly and alternately is lowered, and the method has the advantage of the tail end of the boom moving stably.

Description

Concrete pump truck and boom control method

This application claims priority to Chinese Patent Application No. 201410036995.7, entitled "A Concrete Pump Truck and Boom Control Method", filed on January 26, 2014, the entire contents of which are incorporated by reference. In this application.

Technical field

The invention relates to the field of engineering machinery, in particular to a concrete pump truck and a boom control method.

Background technique

The boom of the concrete pump truck is generally articulated by four arms or five arms or six arms, and the concrete is transported to the target pouring point through the boom. The usual boom control mode is that the operator uses the remote controller to adjust the posture of each arm separately, so that the whole arm moves from the initial posture to the target posture. This method is complicated and low in efficiency.

In view of the shortcomings of the above control methods, the proposed intelligent control method of the boom can determine the values of each degree of freedom by the equation of motion and various matrix transformations according to the coordinates of the target point and the relevant parameters of each arm, and the inverse solution is used. As a result, multiple sets of solutions will appear. For a multi-degree-of-freedom boom, the end of the boom is moved to the target point, and each arm has a different posture, so it is necessary to determine a set of better solutions as the actual control strategy. At present, it is more complicated to determine an optimal solution, and the control effect is not good.

In order to solve the above technical problem, the CN201110197146.6 patent discloses "a control method and a control device for a construction machine and a robot arm", which uses a two-degree-of-freedom robot arm for each movement and follows the arm arm displacement amount. The minimum principle is to determine the two booms that need to be actuated according to the control command by a predefined "slope". Although this simplifies the algorithm, it will cause the two arm movements of the adjustment to be abrupt, the movement of the boom is discontinuous, and the stability of the boom is poor. In addition, if the boom encounters an obstacle, there will be problems such as uncontrollable. Moreover, each arm is driven by a hydraulic cylinder. During the actual movement of the boom, the amount of expansion and contraction of the hydraulic cylinder is a nonlinear function relationship with the angular change of each arm. Even if the displacement of the hydraulic cylinder is small, the angle of the arm will be caused. Significant changes that cause mutations and instability problems.

At the same time, for the flexible inertia pump truck boom control system with large inertia, it often appears because of the objective reasons such as the control accuracy of the oil inlet cylinder of each section, the control accuracy of the boom rotation angle and the inertia of the boom. The end of the boom is offset from the target moving direction. As shown in Figure 1, in the direction of the target movement AB, the movement trend of the end of the boom is shortened. When the end of the planning boom moves, the step of moving the end of the boom is determined according to the opening signal of the remote control action signal, P1 and P2 is the next target point for the end movement planning of the boom. If the end of the boom deviates from the point P1 and reaches the point S1, the boom will move from the point S1 to the point P2 according to the original plan. This will shorten the end of the boom from point A to point S1, and the boom will be elongated from point S1 to point P2, causing the plan to move in the opposite direction to the end of the boom in the target moving direction. The arm frame is stretched and shortened repeatedly, causing the arm end to move unevenly.

Summary of the invention

In view of this, the present invention proposes a concrete pump truck and boom control method to reduce the problem that the boom is elongated and shortened repeatedly during the movement of the boom, and the movement of the end of the boom is not stable.

In one aspect, the present invention provides a boom control method including real-time acquisition of a remote controller motion signal, a current state angle signal of each arm of the boom, and a boom rotation angle signal to plan movement of the boom end, and also includes Predictive control, the predictive control comprising:

Calculating a coordinate value of the end point of the boom in real time according to the target moving direction of the end of the boom, and if the end point of the boom deviates from the moving direction of the target, performing secondary planning on the end of the boom, The secondary plan outputs the next target point.

Further, the predictive control further includes the following steps:

Predicting the boom extension region and/or the boom shortening region according to the target moving direction;

If the end of the boom is located in the elongated region of the boom and deviates from the moving direction of the target, performing a secondary plan for elongating the boom to the end of the boom;

If the end of the boom is at the shortening area of the boom and deviates from the target moving direction, a secondary plan for shortening the boom is performed on the end of the boom.

Further, a vertical point that is the shortest distance from the center of rotation of the boom is found in the target moving direction, and the area from the vertical point to the moving direction of the target is the extended area of the boom, and The side is the shortening area of the boom.

Further, an area is defined around the vertical point as a boom expansion and contraction conversion area, and if the arm end point is in the boom expansion and contraction conversion area, the predictive control is turned off.

Further, the plan for moving the end of the boom includes:

Step 1: Establish a mathematical model according to the current position of the boom to the next target position, and establish a target constraint function according to the principle of minimum arm movement and stability of each arm;

Step 2: calculating, according to the motion signal of the remote controller, the current state angle signal of each arm of the boom, and the rotation angle signal of the boom, obtaining the angle of the arm extension and the target rotation angle of the boom;

Step 3: determining whether the angle of the arm of each section exceeds the range of the boom angle of the boom;

Step 4: If all the boom angles are exceeded, stop the control boom motion; if the section boom angle is exceeded, return to step 2 to recalculate.

Further, the target constraint function includes the following formula:

OBJ ₁ =∑w _i ·(θ _i -θ _i-1 ) ²

OBJ ₂ =∑w _i ·((θ _i -θ _i-1 )-(θ _i-1 -θ _i-2 )) ²

Where w _i represents the weight of the i-section arm; θ _i represents the i-section arm target angle, θ _i-1 represents the current angle of the _i- section arm, and θ _i-2 represents the angle of the previous step of the i-section arm.

Further, if the i-section arm is locked by the operating hand, w _i is zero.

Further, in the step 2, the spatial trajectory planning is divided into a boom rotation and a mechanical arm plane expansion, respectively, and the respective section arm expansion angles and the boom target rotation angles are respectively obtained.

Further, the mathematical model is as follows:

Where θ _min ≤ θ _i ≤ θ _max , θ _i is the angle between the i-section arm and the i-1-section arm, θ _min represents the minimum buck angle of the i-section arm, and θ _max represents the maximum buck angle of the i-section arm, θ ₀ is the rotation angle, l _i is the length of each arm, x _end , y _end , z _end is the end point coordinate, and N is the number of the arm of the boom.

Further, the present invention provides a concrete pump truck comprising a boom and using the boom control method of any of the above.

The invention provides a concrete pump truck and boom control method, which adds a predictive control program, and calculates the coordinate value of the end point of the boom in real time according to the target moving direction at the end of the boom. If the end of the boom deviates from the target moving direction, Then the second end of the boom end is planned, and the second plan outputs the next target point. Because the end of the boom is deviated from the target moving direction, the end of the boom is quadraticized, and the motion of the boom is no longer controlled according to the original plan, so that the end point of the boom always moves toward the target point, and the boom is lowered. Elongation and shortening the possibility of repeated alternating operations, making the end of the boom more stable.

In a further technical solution, the boom extension region and/or the boom shortening region are predicted according to the target moving direction of the boom end as a limitation condition for the boom motion planning. If the end of the boom is at the extension of the boom and deviates from the target moving direction, the end of the boom is moved to make a secondary plan for elongating the boom; if the end of the boom is in the shortened area of the boom and deviates from the target The direction of movement, the movement of the end of the boom to make a secondary plan to shorten the boom. According to the next target point of the secondary planning, the calculation of the end movement of the boom is carried out, and the corresponding arm rotation angle and the folding angle of each arm are obtained, so that the boom planning scheme and the target moving direction of the boom movement trend are consistent, further It avoids the extension of the boom or shortens the repeated alternating movements, and the boom moves smoothly.

In addition, during the planning of the boom movement, the target constraint function is established according to the principle of minimum arm movement and motion stability, and the target constraint function is used to determine an optimal solution to achieve the continuity of the boom movement. At the same time, the improvement is achieved. The stability and accuracy of the movement of the boom prevent the unstable movement of the boom, and reduce the movement of the arms and save energy and reduce emissions.

In order to simplify the calculation, it is preferred to divide the spatial trajectory planning into the jib rotation and the mechanical arm plane to be separately calculated, and obtain the angle of each section arm and the target rotation angle of the jib respectively, and then judge whether the boom movement range is exceeded or not. The purpose of the arm frame intelligent control.

In order to further improve the continuity and smooth performance of the boom movement, the relationship between the articulated linkage mechanism of the boom is also considered, the kinematics and dynamics relationship are integrated, the trajectory algorithm is adjusted, and the current is controlled as a ramp function. In order to increase the working range of the boom and prevent the boom from colliding with the obstacle, the arm locking function is added. If the arm is locked by the operating hand, the weight of the arm is zero. The operator can lock the arbitrary target arm according to the current boom attitude to realize the trajectory planning of the target point, which makes the operation more flexible. Live, expanding the scope of construction operations and the versatility of the boom planning strategy.

DRAWINGS

The accompanying drawings, which are incorporated in the claims In the drawing:

1 is a schematic view of a conventional boom control method;

2 is a schematic flow chart of a method for predicting and controlling a boom according to the present invention;

3 is a schematic view showing the principle of the boom control of the present invention;

4 is a schematic flow chart of the end movement planning of the boom of the present invention;

FIG. 5 is a schematic flow chart of the calculation process of the end movement of the boom of the present invention.

detailed description

It should be noted that the embodiments in the present invention and the features in the embodiments may be combined with each other without conflict. The invention will be described in detail below with reference to the drawings in conjunction with the embodiments.

The invention provides a boom control method, which comprises real-time acquiring a motion signal of a remote controller and a current state angle signal of each arm of the boom and a rotation angle signal of the boom, planning the movement of the end of the boom, and further including predictive control. The predictive control includes:

According to the target moving direction at the end of the boom, the coordinate value of the end point of the boom is calculated in real time. If the end point of the boom deviates from the target moving direction, the end of the boom is secondarily planned, and the secondary planning outputs the next target point.

It should be noted that the deviation of the end point of the boom from the target moving direction refers to a certain range deviating from the moving direction of the target. Therefore, it should be understood that the deviation may be a certain error, that is, the deviation from the target moving direction within the error range may not be performed. Secondary planning, beyond the error range, requires secondary planning. According to the control accuracy, an appropriate error range can be set.

In the present invention, since the end of the boom is deviated from the target moving direction, the end of the boom is secondarily planned, that is, from the current point of the boom end to the target point, and the boom motion is no longer controlled according to the original planned scheme. The arm end point is always moved toward the target point, which reduces the possibility of the arm frame elongating and shortening the repeated alternate operation, so that the end of the arm frame moves more smoothly.

As shown in FIG. 2 and FIG. 3, a preferred boom control method according to the present invention includes predictive control, and the predictive control preferably includes: predicting the boom extension region and/or the boom according to the target moving direction AB at the end of the boom. Shorten the area; calculate the coordinates of the end point of the boom in real time. If the end of the boom is in the extended area of the boom, and the end point of the boom deviates from the target moving direction AB, the secondary planning of the boom extension is performed on the end of the boom. If the end of the boom is at the shortened area of the boom, and the end point of the boom deviates from the target moving direction AB, the secondary planning of shortening the boom is performed on the end of the boom, and the next target points H1 and H2 are output by the secondary planning.

It should be noted that the secondary planning to extend the boom and the secondary planning to shorten the boom should be understood to include the case where the boom remains unchanged, that is, in the extended region, the boom does not change the tendency of elongation. In the shortened area, the boom does not change the tendency to shorten. Therefore, in the extended region of the boom, the boom is not shortened, and in the shortened region of the boom, the boom is not elongated, and the boom is further prevented from being extended and the repeated motion is shortened. If the end of the boom is on the boom expansion and contraction transition area, the predictive control is turned off.

Through the mathematical calculation method, predict the boom extension area and the boom shortening area and the boom expansion and contraction conversion area; find the vertical point Q with the shortest distance from the rotation center of the boom in the target moving direction, and the area from the vertical point Q to the target moving direction The boom extension area QB, the opposite side is the boom shortening area AQ, and an area defined around the vertical point Q is the boom expansion and contraction conversion area. Generally, the vertical point Q is centered, and a circle is drawn with a radius of 500 mm as a boom expansion and contraction conversion region. Predictive control is not performed in the boom expansion and contraction conversion area, and the problem that the boom cannot move to the target direction due to the predictive control function is avoided.

The control principle of the boom is as shown in Fig. 3. Obtain the action signal of the remote controller, the current state angle signal of each arm of the boom and the rotation angle signal of the boom. In the target moving direction AB, plan the movement of the end point of the boom at each step. A target point P1, P2, P3, P4, P5, P6, generally the step size of P1 to P2 is equal to the step size of P2 to P3, and the step size of P4 to P5 is equal to the step size of P5 to P6. At the same time, the remote control action signal is also collected in real time, and each target point is updated in real time according to the remote action signal.

Assume that the current position A of the boom end point moves to the point P1, and the coordinate values of the current position A of the boom end point and the next target point P1 are calculated, and the arm end movement is performed according to the current position A of the boom to the next target point P1. Planning calculation; obtaining the angle of the arm of each section and the angle of rotation of the target of the boom (the angle of rotation is the angle of rotation of each arm around its hinge point, and the target rotation angle of the boom is the need of the turntable of the entire boom device around the connecting arm) The angle of rotation).

Due to the objective reasons such as the control accuracy of the oil-increasing cylinder of each arm, the control accuracy of the boom rotation angle and the inertia of the boom, the end point of the boom deviates from the target moving direction AB, and the end point of the boom reaches the point S1. At this time, it is necessary to judge whether the boom end point S1 is in the boom extension region or in the boom shortening region or the boom conversion region. After judging that the boom end point S1 is in the boom shortening area, it is necessary to perform secondary planning on the next target point H1 at the end of the boom, and cannot move according to the previous planned target point P2. Otherwise, the boom will elongate and shorten the alternate action, causing the boom to move unsteadily. When planning for the next target point H1, it is necessary to consider shortening the boom as a constraint for secondary planning. The end point of the boom is from point A to point S1, the boom is shortened, the end point of the boom is from point S1 to point H1, and the boom is also shortened, so that the end of the boom is in the shortened area of the boom, and the boom is always Shortened, the boom movement is not stable.

Assume that the end point of the boom moves from P4 to P5. Due to the objective reasons such as the control accuracy of the oil cylinder of each section arm, the control accuracy of the boom rotation angle and the inertia of the boom, the end point of the boom deviates from the target moving direction AB. The end of the boom reaches the point S2. At this time, the boom end point S2 is in the boom extension region, and the next target point H2 at the end of the boom needs to be quadraticized, and cannot be moved according to the previous planned target point P6. Otherwise, the boom will elongate and shorten the alternate action, causing the boom to move unsteadily. When planning for the next target point H2, it is necessary to consider the extension of the boom as a constraint for the secondary planning. The end of the boom is from P4 to S2, the boom is elongated, the end of the boom is from S2 to H2, and the boom is also elongated, so that the end of the boom is in the extended area of the boom, the boom It has always been stretched and the boom movement is not stable.

As shown in Figures 4 and 5, when the end of the planning boom moves, it includes:

Step 1: Establish a mathematical model according to the current position of the boom to the next target position, and establish a target constraint function according to the principle of minimum arm movement and smoothness of each arm;

Step 2: According to the remote action signal, the current state angle signal of each arm of the boom, and the current rotation angle signal of the boom, the angle of the boom extension and the target rotation angle of the boom are obtained through calculation;

Step 3: Determine whether the angle of the arm of each section exceeds the range of the boom angle;

Step 4: If all the boom angles exceed the boom angle range, stop the control boom motion; if the section boom angle exceeds the boom bracket angle range, return to step 2 to recalculate, otherwise, the control arm Frame action.

The specific implementation is as follows:

1) Establish a coordinate system

The hinge position of the concrete pump truck turntable and the starting end of the boom frame is taken as the coordinate origin, and the hopper direction of the vehicle body is the X positive half shaft, and the direction perpendicular to the vehicle body is the positive half axis of the Y axis, according to the right hand rule of the Cartesian coordinate system. The Z axis can be determined. This coordinate system is the reference coordinate system of the boom intelligent motion system, that is, the motion planning strategy for the boom design is based on the coordinate system.

2) receiving, by the signal acquisition device, the action signal of the remote controller, the current state angle signal of each arm of the boom, and the current rotation angle signal of the boom. The remote control action signal includes a direction signal and a speed signal of the operation handle, and the signal acquisition device receives the action signal of the remote control device through the wireless signal receiving device, and acquires the current state angle signal of each arm of the boom and the current rotation angle signal of the boom through the angle sensor.

3) Establish a mathematical model for the trajectory planning of the boom space

Before designing a multi-degree-of-freedom boom motion planning strategy, you first need to establish a system mathematical model. According to the kinematics of the boom structure, based on the above established coordinate system, the mathematical model is:

Where θ _min ≤ θ _i ≤ θ _max , θ _i is the angle between the i-section arm and the i-1-section arm, θ _min represents the minimum buck angle of the i-section arm, and θ _max represents the maximum buck angle of the i-section arm; ₀ is the rotation angle; l _i is the length of each arm; x _end , y _end , z _end is the end point coordinate, and N is the number of the arm of the boom.

The spatial trajectory planning is divided into two parts: the boom rotation and the mechanical arm plane expansion, and the calculation results are respectively obtained, and the angles of the booms and the target rotation angles of the booms are respectively obtained.

If only the plane motion of the boom is considered, the above mathematical model is simplified as:

4) Consider the following when building the target constraint function:

First, moving from the current position to the target position, the boom movement is as small as possible, that is, energy saving and emission reduction;

Second, the boom moves smoothly, avoiding drastic speed changes, especially reverse motion.

OBJ ₁ =∑w _i ·(θ _i -θ _i-1 ) ²

OBJ ₂ =∑w _i ·((θ _i -θ _i-1 )-(θ _i-1 -θ _i-2 )) ²

Where w _i represents the weight of the i-section arm, θ _i represents the i-section arm target angle, θ _i-1 represents the current angle of the _i- section arm, and θ _i-2 represents the angle of the previous step of the i-section arm.

If the i-section arm is locked by the operator, the weight w _i of the i-section arm is zero.

5) Establish a constrained optimization problem and transform the constrained optimization problem into an unconstrained optimization problem.

Next, add a penalty factor to transform the constrained optimization problem into an unconstrained optimization problem.

Therefore, only the solution of g(θ) is required.

As shown in Figure 4, the specific steps are as follows:

Step 1: Set the initial value, set the current state angle signal of each arm of the obtained boom to the initial value, and set the current rotation angle signal of the boom to the initial value;

Step 2: Calculate the step size h or adopt a negative gradient method using a one-dimensional linear search method;

In the third step, if ceq ₁ , ₂ (x) < ε and θ _imin ≤ θ _i ≤ θ _imax , exit;

The fourth step, otherwise jump to the second step.

6) A certain arm is locked during the movement of the boom;

During the movement, if a certain arm is unable to move due to human or structural reasons, it is necessary to reduce one-dimensional or multi-dimensional degrees of freedom in planning strategy design. Specifically divided into two cases:

First, if the boom rotation cannot meet the input command requirements, the motion is stopped;

Second, if a certain arm of the boom is locked, the current arm posture is recorded, and the weight w _i of the i-section arm is 0 through the plan motion of the joint arm plane.

7) obtaining the angle of the arm extension and the target rotation angle of the boom by calculation;

8) Determine whether the angle of the arm of each section exceeds the range of the boom angle; if all the angles of the arm are exceeded, stop the control of the boom; if the angle of the section is exceeded, return to step 2 to recalculate, otherwise , control the movement of the boom.

9) In step 4: According to the relationship between the arm angle and the hydraulic cylinder expansion and contraction function of driving the arm movements, it is necessary to fully consider the structural kinematics and dynamics, calculate the hydraulic cylinder expansion and contraction amount, and control the electromagnetic cylinder to electromagnetic exchange. The control current is input to the valve, and the control current is a ramp function instead of a rectangular function to ensure the continuity and smoothness of the boom movement.

10) If the remote control stops, stop the boom movement; if the remote control continues to move, return to step 1.

The invention provides a boom control method, which establishes a target constraint function according to the principle of minimum arm movement and motion stability of each arm; and determines an optimal solution by the target constraint function to realize the continuity of the boom motion; Improve the stability and precise control of the movement of the boom, prevent the unstable movement of the boom from occurring, reduce the amount of movement of each arm, and play the role of energy saving and emission reduction.

In addition, in order to simplify the calculation, the spatial trajectory planning is divided into the jib rotation and the mechanical arm plane to be separately calculated, and the angle of each arm and the target rotation angle of the jib are respectively obtained, and then it is judged whether the movement range of the jib is exceeded or not Collision with obstacles, the purpose of intelligent control of the boom.

In order to further improve the continuity and smooth performance of the boom movement, the relationship between the articulated linkage mechanism of the boom is also considered, the kinematics and dynamics relationship are integrated, and the trajectory algorithm is adjusted. The control current is a ramp function.

In order to increase the working range of the boom and prevent the boom from colliding with the obstacle, the arm locking function is added. If the i-section arm is locked by the operating hand, the weight w _i of the i-section arm is 0, so that the operator can follow the current arm. The posture of the frame is locked by any arm, and the trajectory planning of the target point is realized, which makes the operation more flexible, and expands the scope of construction work and the versatility of the boom planning strategy.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are included in the spirit and scope of the present invention, should be included in the present invention. Within the scope of protection.

Claims

A boom control method includes real-time acquisition of a motion signal of a remote controller, a current state angle signal of each arm of the boom, and a rotation angle signal of the boom, and planning the movement of the end of the boom, which is characterized in that it also includes predictive control. The predictive control includes:

Calculating a coordinate value of the end point of the boom in real time according to the target moving direction of the end of the boom, and if the end point of the boom deviates from the moving direction of the target, performing secondary planning on the end of the boom, The secondary plan outputs the next target point.
The boom control method according to claim 1, wherein the predictive control further comprises the following steps:

Predicting the boom extension region and/or the boom shortening region according to the target moving direction;

If the end of the boom is located in the elongated region of the boom and deviates from the moving direction of the target, performing a secondary plan for elongating the boom to the end of the boom;

If the end of the boom is at the shortening area of the boom and deviates from the target moving direction, a secondary plan for shortening the boom is performed on the end of the boom.
The boom control method according to claim 2, wherein a vertical point that is the shortest distance from the center of rotation of the boom is found in the target moving direction, and the area from the vertical point to the moving direction of the target is the The boom extension region, the opposite side is the boom shortening region.
The boom control method according to claim 3, wherein a region defined around the vertical point is a boom telescopic conversion region, and if the boom end point is in the boom telescopic conversion region, Turn off predictive control.
The boom control method according to any one of claims 1 to 4, wherein the plan for moving the end of the boom comprises:

Step 1: Establish a mathematical model according to the current position of the boom to the next target position, and establish a target constraint function according to the principle of minimum arm movement and stability of each arm;

Step 2: calculating, according to the motion signal of the remote controller, the current state angle signal of each arm of the boom, and the rotation angle signal of the boom, obtaining the angle of the arm extension and the target rotation angle of the boom;

Step 3: determining whether the angle of the arm of each section exceeds the range of the boom angle of the boom;

Step 4: If all the boom angles are exceeded, stop the control boom motion; if the section boom angle is exceeded, return to step 2 to recalculate.
The boom control method according to claim 5, wherein the target constraint function comprises the following formula:

OBJ 1 =∑w i ·(θ i -θ i-1 ) 2

OBJ 2 =∑w i ·((θ i -θ i-1 )-(θ i-1 -θ i-2 )) 2

Where w i represents the weight of the i-section arm; θ i represents the i-section arm target angle, θ i-1 represents the current angle of the i- section arm, and θ i-2 represents the angle of the previous step of the i-section arm.
The boom control method according to claim 6, wherein if the i-section arm is locked by the operating hand, w i is zero.
The boom control method according to claim 5, wherein in the step 2, the spatial trajectory planning is divided into a boom rotation and a mechanical arm plane expansion, respectively, and the respective section arms are respectively obtained. Angle and boom target rotation angle.
The boom control method according to claim 5, wherein the mathematical model is as follows:

Where θ min ≤ θ i ≤ θ max , θ i is the angle between the i-section arm and the i-1-section arm, θ min represents the minimum buck angle of the i-section arm, and θ max represents the maximum buck angle of the i-section arm, θ 0 is the rotation angle, l i is the length of each arm, x end , y end , z end is the end point coordinate, and N is the number of the arm of the boom.
A concrete pump truck comprising a boom, characterized in that the boom control method according to any one of claims 1 to 9 is employed.