WO2021026779A1

WO2021026779A1 - Cradle head control method and device, cradle head and storage medium

Info

Publication number: WO2021026779A1
Application number: PCT/CN2019/100433
Authority: WO
Inventors: 卢国政
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2021-02-18
Also published as: CN112272806A

Abstract

A cradle head control method and device, a cradle head and a storage medium, the cradle head at least comprising a first support (101), a second support (102) and a third support (103) used for connecting a load, which are connected in sequence. The cradle head control method comprises: detecting whether the cradle head is located in a preset singular point neighborhood (S1); when the cradle head is located in the the singular point neighborhood, obtaining a target end attitude of the cradle head and measuring the end attitude (S2); calculating a single-axis control component and a dual-axis control component according to the target end attitude and the measured end attitude, the single-axis control component relating to the first support, and the dual-axis control component relating to the second support and the third support (S3); and controlling the first support according to the single-axis control component, and controlling the second support and the third support according to the dual-axis control component (S4).

Description

PTZ control method, device, PTZ and storage medium

Technical field

The invention relates to the field of control, and in particular to a pan-tilt control method, device, pan-tilt and storage medium.

Background technique

Physically, a point that exists but does not exist is called a singularity (or singularity). In the mechanical field, a singular point can mean that the end of the robotic arm loses a certain degree of freedom in a certain direction when the robot arm is in a certain combination of joint positions.

At present, when the gimbal is at the singular point and its neighborhood, because the Jacobian matrix corresponding to the gimbal is singular or close to singular, the speed measured by the end inertial measurement module is mapped to the joint angle space through the Jacobian inverse matrix The angular velocity and its noise will be very large, which will affect the stability of the pan/tilt control and make it difficult to achieve accurate attitude control.

Summary of the invention

The invention provides a pan/tilt control method, device, pan/tilt and storage medium, which are used to solve the problems in the prior art that the stability of the pan/tilt control is affected by the neighborhood of singular points, and it is difficult to achieve accurate posture control.

The first aspect of the present invention is to provide a pan-tilt control method, the pan-tilt at least includes a first support, a second support and a third support for connecting a load connected in sequence; the method includes:

Detecting whether the PTZ is located in the neighborhood of a preset singularity;

When the pan/tilt is located in the neighborhood of a singular point, acquiring the target end attitude and the measurement end attitude of the pan/tilt;

The single-axis control component and the dual-axis control component are calculated according to the target end attitude and the measured end attitude; wherein the single-axis control component is related to the first support, and the dual-axis control component is related to the second support and The third bracket is related;

The first bracket is controlled according to the single-axis control component, and the second bracket and the third bracket are controlled according to the dual-axis control component.

The second aspect of the present invention is to provide a control device for a pan/tilt head, the pan/tilt head at least includes a first bracket, a second bracket and a third bracket for connecting a load, which are connected in sequence; the control device includes:

Memory, used to store computer programs;

The processor is configured to run a computer program stored in the memory to realize: detecting whether the pan/tilt is located in the neighborhood of a preset singularity; when the pan/tilt is located in the neighborhood of the singularity, acquiring the information of the pan/tilt The target end posture and the measurement end posture; the single-axis control component and the dual-axis control component are calculated according to the target end posture and the measured end posture; wherein, the single-axis control component is related to the first bracket, and the dual-axis control The component is related to the second support and the third support; the first support is controlled according to the single-axis control component, and the second support and the third support are controlled according to the dual-axis control component.

The third aspect of the present invention is to provide a pan-tilt control device, the pan-tilt at least includes a first support, a second support and a third support for connecting a load connected in sequence; the control device includes:

The detection module is used to detect whether the pan/tilt is located in the neighborhood of a preset singularity;

An acquiring module, configured to acquire the target end attitude and measurement end attitude of the pan/tilt when the pan/tilt is located in the neighborhood of the singularity;

The calculation module is used to calculate a single-axis control component and a dual-axis control component according to the target end posture and the measured end posture; wherein the single-axis control component is related to the first bracket, and the dual-axis control component is related to the The second bracket is related to the third bracket;

The control module is configured to control the first bracket according to the single-axis control component, and control the second bracket and the third bracket according to the dual-axis control component.

The fourth aspect of the present invention is to provide a pan/tilt head, which is characterized in that it includes at least:

The first support, the second support and the third support for connecting the load connected in sequence;

In the pan-tilt control device of the second aspect described above, the control device is used to control the first bracket, the second bracket, and the third bracket.

The fifth aspect of the present invention is to provide a computer-readable storage medium, the storage medium is a computer-readable storage medium, the computer-readable storage medium stores program instructions, and the program instructions are used in the first aspect. The described PTZ control method.

According to the pan/tilt control method, device, pan/tilt and storage medium provided by the present invention, when the pan/tilt is located in the vicinity of a singular point, the target end attitude of the pan/tilt is acquired and the measured end attitude is determined according to the target end attitude Calculate the single-axis control component and the dual-axis control component with the measurement end attitude, and realize the decoupling of the three brackets into a first bracket and a dual-axis bracket. The dual-axis bracket includes a second bracket and a third bracket. , And use the single-axis control component and the dual-axis control component to decouple the movement of the first bracket, the second bracket, and the third bracket. This not only effectively realizes that when the pan/tilt is located in the neighborhood of the singular point, it can ensure the cloud The stability of the posture of the platform also expands the scope of the posture control of the PTZ, further improves the practicability of the method, and is beneficial to market promotion and application.

Description of the drawings

The drawings described here are used to provide a further understanding of the application and constitute a part of the application. The exemplary embodiments and descriptions of the application are used to explain the application and do not constitute an improper limitation of the application. In the attached picture:

Fig. 1 is a schematic diagram of controlling the PTZ provided in the prior art;

FIG. 2 is a schematic flowchart of a method for controlling a pan-tilt according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a pan-tilt not in the neighborhood of a singular point according to an embodiment of the present invention;

4 is a schematic diagram of a pan-tilt located in the neighborhood of a singular point according to an embodiment of the present invention;

FIG. 5 is a schematic flow chart of calculating a single-axis control component according to the target end pose and the measured end pose provided by an embodiment of the present invention;

6 is a schematic diagram of an algorithm for calculating a single-axis control component based on the target end attitude and the measured end attitude provided by an embodiment of the present invention;

FIG. 7 is a schematic diagram of controlling the target joint angle to the first bracket according to an embodiment of the present invention;

FIG. 8 is a schematic flow chart of calculating a dual-axis control component according to the target end pose and the measured end pose provided by an embodiment of the present invention;

9 is a schematic flowchart of determining the dual-axis control component based on the target end attitude, the measured end attitude, and the end angular velocity according to an embodiment of the present invention;

FIG. 10 is a schematic flowchart of determining the dual-axis control component according to the attitude control error and the terminal angular velocity according to an embodiment of the present invention;

Figure 11 is an embodiment of the present invention for the attitude control error and the end angular velocity, removing the components related to the first support from the attitude control error and the end angular velocity, and generating the second support and the third support Schematic diagram of the flow of related local attitude control error and local end angular velocity;

12 is a schematic diagram of controlling the second bracket and the third bracket according to the dual-axis control component according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of a process of detecting whether the PTZ is located in the neighborhood of a singularity according to an embodiment of the present invention;

14 is a schematic flowchart of another method for controlling a pan/tilt head according to an embodiment of the present invention;

15 is a schematic flowchart of another method for controlling a pan/tilt head according to an embodiment of the present invention;

16 is a schematic flowchart of determining at least one smooth transition signal according to the first driving signal and the second driving signal according to an embodiment of the present invention;

FIG. 17 is a schematic flowchart of obtaining a weighting coefficient corresponding to the first driving signal according to an embodiment of the present invention;

18 is a schematic flowchart of a method for controlling a pan/tilt head provided by an application embodiment of the present invention;

19 is a schematic structural diagram of a pan-tilt control device provided by an embodiment of the present invention;

20 is a schematic structural diagram of a pan-tilt control device provided by an embodiment of the present invention;

21 is a schematic structural diagram 1 of a pan-tilt according to an embodiment of the present invention;

FIG. 22 is a second structural diagram of a pan-tilt according to an embodiment of the present invention;

FIG. 23 is a schematic structural diagram of a movable platform provided by an embodiment of the present invention.

detailed description

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention.

In order to facilitate the understanding of the technical solutions and technical effects of the present application, the following briefly describes the prior art:

In the prior art, the three-axis attitude closed-loop controller of the pan/tilt (for example, handheld pan/tilt) is generally a position loop-speed loop dual-loop controller. As shown in Figure 1, R _tar is the end (camera) target attitude, and R _eb is the end (camera) measurement (fusion) attitude, δR is the attitude control error, C _p is the position loop controller, C _v is the speed loop controller, J ^-1 is the Jacobian inverse matrix, and P is the controlled object (motor ), ω _b is the terminal angular velocity,

For joint angular velocity, Fusion is an inertial measurement unit (IMU) for data fusion; through the above-mentioned end target posture R _tar and end angular velocity, dual-loop closed-loop control of the pan/tilt can be realized. Among them, the Jacobian matrix corresponding to the gimbal describes the nonlinear mapping relationship between the angular velocity of each joint and the velocity in the end body coordinate system of the gimbal. The Jacobian inverse matrix is usually used to map the position loop error and angular velocity to the joint angle space, that is, satisfy the formula

Thus, the control quantity under the body coordinate system is changed to the control quantity of each motor. After the speed loop controller, each motor will obtain the output torque required to realize the attitude control.

on the contrary,

Among them, J is the Jacobian matrix.

However, when the joint angle of the gimbal is in the neighborhood of the singular point, the Jacobian matrix is close to singular (irreversible). At this time, according to the terminal angular velocity ω _b and the joint angular velocity

Relationship

It can be seen that in order to obtain the speed in some directions of the end, the required joint angular velocity

It will be very big. At the same time, because of the Jacobian inverse matrix, the value of some elements will become very large, and the measurement noise of the terminal inertial measurement module will also be amplified by the Jacobian inverse matrix. This easily makes the control of the pan/tilt difficult to stabilize, which makes it difficult to achieve attitude control and stabilization.

In order to solve the above-mentioned problems, the prior art proposes the following solutions: (a) Design structural limits in the neighborhood of singular points. (b) Design software limit in the neighborhood of singularity, or design to avoid trajectory to avoid singularity. (c) Redundant connecting rod design, the singularity is designed in the very useful area.

For the above solution (a) and solution (b), it is mainly to avoid entering the neighborhood of singular points through evasion methods. However, the limits of these methods are generally designed to be far from the singular point (for example: generally above 30 degrees, mainly determined by the configuration and sensor noise), which greatly reduces the range of movement of the gimbal; especially for some configurations For the type of gimbal, in order to meet certain usage requirements, the singularity is closer to the normal working space. For example, the non-orthogonal configuration of the gimbal will have a further reduced range of motion in a certain direction. Regarding the above solution (c), it does not actually solve the problem of singularity neighborhood control, and redundant design increases the volume, weight, design, and material cost.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. Provided that there is no conflict between the various embodiments, the following embodiments and the features in the embodiments can be combined with each other.

Figure 2 is a schematic flow chart of a method for controlling a pan/tilt head provided by an embodiment of the present invention; in order to solve the problem that the stability of the pan/tilt control is affected by the neighborhood of singular points in the prior art, it is difficult to achieve accurate attitude control. As shown in FIG. 2, this embodiment provides a pan/tilt control method, wherein the pan/tilt may at least include a first support, a second support, and a third support for connecting a load, the load may be a camera , Video camera or any other device with shooting function. In addition, the main body of the control method is the pan/tilt control device. It can be understood that the control device can be implemented as software or a combination of software and hardware; when the control device executes the control method, it can be implemented in the pan/tilt relative to When the neighborhood of the singular point is in different states, different control strategies are adopted to control the first bracket, the second bracket and the third bracket in the pan-tilt. Specifically, the method includes:

S1: Check whether the PTZ is located in the neighborhood of the preset singularity.

When the pan/tilt is at a singular point, the minimum value of the singular value of the Jacobian matrix is equal to 0 or the matrix determinant is equal to zero; and when the pan/tilt is located in the neighborhood of the singular point, the Jacobian matrix is close to singularity, that is, the Jacobian The minimum value of the singular value of the matrix is within a preset first range or the matrix determinant is within a preset second range. Specifically, referring to Figures 3-4, the pan/tilt head also includes a first motor 107, a second motor 108, and a third motor 109. One end of the first motor 107 is connected to the first bracket 101 through a rotating member 104. The rotating member 104 is used to enable the first bracket 101 to rotate relative to the first motor 107, so that the pan/tilt can be switched between the storage state and the use state; and the other end of the first motor 107 is connected to the carrier 10, To drive the first support 101 to rotate relative to the carrier 10; the second motor 108 is arranged on the first support 101 for driving the second support 102 to rotate relative to the first support 101; The third motor 109 is disposed on the second support 102 and is used to drive the third support 103 to rotate relative to the second support 102.

The following briefly explains whether the pan/tilt is located in the neighborhood of the singular point: when the pan/tilt is at the singular point, the axis of the first motor 107, the axis of the second motor 108 and the axis of the third motor 109 are on the same plane , That is, the yaw axis, roll axis, and pitch axis of the pan/tilt are located on the same plane, and the second motor 108 is located at the preset joint angle; when the pan/tilt is in the neighborhood of the singular point, the first The axis of the motor 107, the axis of the second motor 108, and the axis of the third motor 109 are located or close to being on the same plane, that is, the yaw axis, roll axis and pitch axis of the pan/tilt are located or approximately on the same plane, so The second motor 108 is located within the preset joint angle range. It should be noted that whether it is an orthogonal pan/tilt or a non-orthogonal pan/tilt, as long as the axis of the first motor 107, the axis of the second motor 108, and the axis of the third motor 109 are on the same plane, it can be regarded as the pan/tilt. At a singularity.

Among them, the singular point neighborhood refers to an angular area located near the singular point. The above-mentioned singular point can be calculated for the PTZ, and the specific range of the neighborhood can be set according to the needs of the user. In addition, this embodiment does not limit the specific implementation of detecting whether the pan/tilt is located in the neighborhood of the singularity. Those skilled in the art can set it according to specific application requirements and design requirements. For example, the Jacques corresponding to the pan/tilt may be obtained. Ratio matrix, the Jacobian matrix judges whether the singular value is less than the preset threshold, or the Jacobian matrix judges whether the matrix determinant is less than the preset threshold, when the singular value is less than or equal to the preset threshold, or the matrix determinant is less than or equal to the preset threshold When the threshold is set, it can be determined that the pan/tilt enters the neighborhood of singularity. Referring to FIG. 9, the detecting whether the PTZ is located in the neighborhood of the singularity in this embodiment may include:

S11: Obtain the joint angle of the second motor.

S12: When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located in the singular point neighborhood. or,

S13: When the joint angle of the second motor is within the angle range corresponding to the neighborhood of the singularity, it is determined that the pan/tilt is located outside the neighborhood of the singularity.

Among them, for a three-axis pan/tilt head including the first bracket, the second bracket and the third bracket, whether the Jacobian matrix is singular is only related to the joint angle of the second motor. Therefore, for the pan/tilt, a simpler singularity determination method is to accurately detect whether the pan/tilt is located in the neighborhood of the singularity through the joint angle corresponding to the second motor. Specifically, the joint angle of the second motor can be obtained through the angle sensor. After the joint angle of the second motor is obtained, the joint angle of the second motor can be compared with the angle range corresponding to the singular point neighborhood. When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it can be determined that the gimbal is located in the singular point neighborhood, where the angle range corresponding to the singular point neighborhood includes: at least two angular boundary values and The intermediate value of any angle between the two angle boundary values; the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood. There are two cases: the joint angle of the second motor is equal to any of the singular point neighborhoods An intermediate value of the angle, the joint angle of the second motor is equal to the boundary value of the angle corresponding to the neighborhood of the singular point. When the joint angle of the second motor is outside the angle range corresponding to the singular point neighborhood, that is, the joint angle of the second motor is neither equal to the angle boundary value nor the angle intermediate value, it can be determined that the gimbal is at the singularity Point outside the neighborhood.

Similarly, when the pan-tilt includes multiple supports, it can be detected whether the pan-tilt is located in the neighborhood of the singularity through the joint angles corresponding to the supports located in the middle part. For example: the pan/tilt includes a first support, a second support, a third support, and a fourth support for connecting the load, and a first motor for driving the first support to rotate relative to the carrier. A second motor that drives the second bracket to rotate relative to the first bracket, a third motor that drives the third bracket to rotate relative to the second bracket, and a fourth motor that drives the fourth bracket to rotate relative to the load When, the second joint angle of the second motor and/or the third joint angle of the third motor can be obtained, and the second joint angle and/or the third joint angle can be used to detect whether the pan/tilt is located in the neighborhood of the singular point; When the second joint angle and/or the third joint angle are within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located in the singular point neighborhood. Alternatively, when the second joint angle and/or the third joint angle are outside the angle range corresponding to the singular point neighborhood, it can be determined that the pan/tilt is outside the singular point neighborhood.

By obtaining the joint angle of the second motor, and then detecting whether the pan/tilt is located in the neighborhood of the singularity based on the joint angle of the second motor, not only can the accuracy of detecting whether the pan/tilt is located in the neighborhood of the singularity be ensured, but also improve The efficiency and quality of data processing ensure the quality and efficiency of PTZ detection.

S2: When the gimbal is located in the neighborhood of the singular point, obtain the target end attitude of the gimbal and measure the end attitude.

When it is determined that the gimbal is located in the neighborhood of the singular point, the target end posture and the measurement end posture of the gimbal can be obtained, where the target end posture can refer to the final posture that the load (camera) needs to reach on the gimbal, and the measurement end posture It can be a pointer to the current attitude measured by the load (camera) on the PTZ. In general, the end posture of the target can be specified by the user or input by the user, or the end posture of the target can be obtained by calculating the related parameters of the pan/tilt; while the end posture of the measurement can be obtained by detecting the load by the detection device, or, also It can be obtained by data fusion according to the inertial measurement unit (IMU) at the end. Specifically, an IMU can contain a three-axis accelerometer and a three-axis gyroscope, fusing the data of the three-axis accelerometer and the three-axis gyroscope, The end posture can be calculated. In another embodiment, an IMU may include a three-axis accelerometer, a three-axis gyroscope, and a three-axis magnetometer. By fusing the three-axis accelerometer, the three-axis gyroscope, and the three-axis magnetometer, the end posture can be calculated.

S3: Calculate the single-axis control component and the dual-axis control component according to the target end posture and the measured end posture; wherein the single-axis control component is related to the first support, and the dual-axis control component is related to the second support and the third support.

After obtaining the target end attitude and the measurement end attitude, the target end attitude and the measurement end attitude can be analyzed and processed, so that the single-axis control component related to the first bracket and the dual-axis control component related to the second bracket and the third bracket can be obtained. Axis control component. It should be noted that for the first bracket, the second bracket and the third bracket, the single-axis control component is only related to the first bracket, and it is not related to the second and third brackets; the dual-axis control component is only related to the first bracket. The second bracket is related to the third bracket, which is not related to the first bracket.

S4: Control the first bracket according to the single-axis control component, and control the second bracket and the third bracket according to the dual-axis control component.

After the single-axis control component is obtained, the first support can be controlled according to the single-axis control component. After the dual-axis control component is obtained, the second support and the third support can be controlled according to the dual-axis control component. The existing three-axis attitude closed-loop controller is equivalently decoupled into two controllers. One controller is used to control the first support, and the other is used to control the second support and the third support. In this way, The second bracket and the third bracket can be equivalent to a dual-axis gimbal, and the corresponding Jacobian matrix dimension is reduced to two-dimensional, which solves the problem of the singularity of the three-dimensional Jacobian matrix and avoids the singularity of the gimbal. The neighborhood affects the stability of the control of the PTZ, which effectively ensures the precise control of the PTZ attitude.

The pan/tilt control method provided in this embodiment detects whether the pan/tilt is located in the neighborhood of the singular point. When the pan/tilt is located in the neighborhood of the singular point, the target end attitude and the measurement end attitude of the pan/tilt are acquired, and the target end attitude and the measurement end The single-axis control component and the dual-axis control component of the attitude calculation realize the decoupling of the three brackets into a first bracket and a dual-axis bracket. The dual-axis bracket includes the second bracket and the third bracket, and they are respectively The single-axis control component and the dual-axis control component are used to decouple the movement of the first bracket, the second bracket, and the third bracket, which not only effectively realizes that when the pan/tilt is located in the neighborhood of the singular point, it can ensure the attitude of the pan/tilt. It is stable, and also expands the range of attitude control of the PTZ, further improves the practicability of the method, and is beneficial to market promotion and application.

Fig. 5 is a schematic diagram of a flow chart for calculating a single-axis control component based on the target end posture and a measured end posture provided by an embodiment of the present invention; Fig. 6 is an algorithm for calculating a single-axis control component based on the target end posture and the measured end posture provided by an embodiment of the present invention Schematic diagram; on the basis of the above embodiment, continue to refer to Figures 5 to 6, this embodiment does not limit the specific implementation of calculating the single-axis control component based on the target end posture and the measured end posture. Those skilled in the art It can be set according to specific application requirements and design requirements. Preferably, the single-axis control component can be obtained through the motor on the pan/tilt. At this time, referring to Figure 3, the motor on the pan/tilt may include the first motor 107. A second motor 108 and a third motor 109. One end of the first motor 107 is connected to the first support 101, and the other end is connected to the carrier 10 for driving the first support 101 to rotate relative to the carrier 10; The second motor 108 is arranged on the first bracket 101, and is used to drive the second bracket 102 to rotate relative to the first bracket 101; the third motor 109 is arranged on the second bracket 102, It is used to drive the third bracket 103 to rotate relative to the second bracket 102.

Specifically, calculating the single-axis control component based on the target end attitude and the measured end attitude may include:

S31: Obtain the first measured joint angle, the second measured joint angle, and the third measured joint angle corresponding to the first motor, the second motor, and the third motor, respectively.

Specifically, the angle detection device can be used to detect the angle of the joint where the first motor is located, so that the first measured joint angle corresponding to the first motor can be obtained. Similarly, the angle detection device is used to separately detect the joint and the joint where the second motor is located. The angle detection is performed on the joint where the third motor is located, so that the second joint angle corresponding to the second motor and the third joint angle corresponding to the third motor can be obtained.

S32: According to the target end posture, the measured end posture, the first measured joint angle, the second measured joint angle, and the third measured joint angle, a Newton iterative algorithm is used to determine the target joint angle corresponding to the first motor.

Among them, the Newton iterative algorithm is a method of numerical calculation in the inverse kinematics solution technology, and the inverse kinematics solution is used to calculate the joint angle corresponding to the end pose. For orthogonal configurations and some simple non-orthogonal configurations, inverse kinematics has analytical solutions, but for complex non-orthogonal configurations or considering the non-orthogonal errors introduced by orthogonal configurations during assembly, general There is no unified inverse kinematics analytical solution for connecting rod configuration. In the absence of an analytical solution for inverse kinematics, the solution can usually be calculated by numerical methods, such as Newton's iterative algorithm.

In the process of using the Newton iterative algorithm to determine the target joint angle corresponding to the first motor, because the initial value of the Newton iterative algorithm must be near the true value (the required target solution), it is also in order to speed up the iteration speed in the initial stage of the iteration. , The initial value of the iterative joint angle can be set to the three joint angle measurement values at the moment of entering the singular control neighborhood. The three joint angle measurements can refer to the first measured joint angle corresponding to the joint where the first motor is located. The second measurement joint angle corresponding to the joint where the second motor is located and the third measurement joint angle corresponding to the joint where the third motor is located.

In addition, the Newton iterative algorithm uses the Jacobian matrix. Since the Jacobian matrix is invertible except for the neighborhood of singular points, the newton iterative algorithm can be used to determine the target joint angle corresponding to the first motor. The iteration step size λ when entering the singular point neighborhood makes the Jacobian matrix always converge in other regions except the singular point neighborhood; among them, when the iteration step size λ is adjusted, the closer the singular point is, The smaller the iteration step size is to adjust the iteration step size. It should be noted that no matter what adjustments are made to the iteration step size, you only need to limit the iteration result not to be equal to the singular point angle (considering the CPU calculation accuracy, limit the iteration result not to be in the neighborhood of the extremely small singular point) to obtain inverse kinematics Solution.

Specifically, when determining the target joint angle corresponding to the first motor, referring to FIG. 6, the following steps are included:

(32.1) After obtaining the first measurement joint angle, the second measurement joint angle, and the third measurement joint angle, the first axis and the first axis of the first motor, the second motor and the third motor at the preset initial positions can be obtained. The second axis and the third axis, where the preset initial position may refer to the position where the motor joint angle of the first motor, the second motor and the third motor is 0°. In addition, the first axis and the second axis Both the and the third axis can be vectors representing information. Then, the forward kinematics formula and the parameters obtained above are used to calculate the measured joint posture corresponding to the measured joint angle θ.

Among them, R _j is the measured joint posture corresponding to the first motor, the second motor and the third motor. The measured joint posture is the difference between the end posture and the handle posture. For example, the measured joint posture can be the difference between the end posture and the handle posture. Difference. In addition, ξ ₁ is the axis of the first motor at the preset initial position (in the body coordinate system), ξ ₂ is the axis of the second motor at the preset initial position (in the body coordinate system), and ξ ₃ is the third motor Preset the axis of the initial position (under the body coordinate system),

Is the axial antisymmetric matrix of the first motor at the preset initial position (under the body coordinate system),

Is the axial antisymmetric matrix of the second motor at the preset initial position (under the body coordinate system),

Is the axial antisymmetric matrix of the third motor at the preset initial position (under the body coordinate system); θ ₁ , θ ₂ and θ ₃ are the first motor corresponding to the first motor, the second motor and the third motor. Measure the joint angle, the second measurement joint angle, and the third measurement joint angle; in specific applications, the above θ ₁ , θ ₂ and θ ₃ can refer to the three joint angle measurement values at the moment of entering the neighborhood of the singular point (respectively with the first One motor, the second motor and the third motor correspond). Preferably, the joint angle can be measured by sensors such as Hall sensors and magnetic encoders.

(32.2) After the measured joint posture R _{j is} obtained, the measured joint posture R _j and the measured end posture (measurement camera posture) R _eb can be used to calculate the handle measurement posture R _h .

R _h ＝R _eb R _j ^-1

Among them, R _h is the measured posture of the handle, _Reb is the measured end posture, and R _j ^-1 is the inverse matrix of the measured joint posture. In another embodiment, the measured posture of the handle may be calculated by fusion of a vision sensor or an IMU and a compass.

(32.3) Use forward kinematics formula and Newton iteration algorithm to calculate the target joint angle of the kth iteration

The target joint pose corresponding to the iteration

among them,

Is the target joint pose corresponding to the target joint angle of the kth iteration,

as well as

Are the first axis, the second axis, and the third axis of the first motor, the second motor, and the third motor at the preset initial positions, respectively;

with

It is the first target joint angle, the second target joint angle, and the third target joint angle corresponding to the first motor, the second motor, and the third motor respectively during K iterations.

(32.4) After obtaining the target joint pose

After that, the posture R _h and the iterated target joint posture can be measured by the handle

Calculate the iterative target end pose

among them,

Is the end attitude of the target in the Kth iteration, R _h is the measured attitude of the handle,

Is the target joint pose corresponding to the target joint angle of the Kth iteration.

(32.5) In obtaining the target end attitude

After that, the iterative target end pose can be calculated

Iterative attitude error ΔR ^(k) from the target end attitude R _tar .

Among them, ΔR ^(k) is the iterative attitude error,

Is the target end attitude in the Kth iteration, R _tar is the target end attitude.

(32.6) Convert the iterative attitude error ΔR ^(k) into the axis angle representation δθ ^(k) .

(32.7) Use the iterative target joint angle

Calculate the corresponding Jacobian matrix

among them,

Is the Jacobian matrix corresponding to the target joint angle of K iterations,

as well as

with

These are the first target joint angle, the second target joint angle, and the third target joint angle corresponding to the first motor, the second motor, and the third motor during K iterations.

(32.8) Using the Jacobian matrix, calculate the iterative joint angle error Δθ ^{(k) of the} target joint angle.

Where Δθ ^(k) is the iterative joint angle error corresponding to the target joint angle,

Is the inverse matrix of the Jacobian matrix; δθ ^(k) is the axis angle representation of the iterative attitude error.

(32.9) Update the k+1th iteration target joint angle.

among them,

To perform the iterative target joint angle of the K+1th iteration, the iterative target joint angle may include the first target joint angle corresponding to the first motor

The second target joint angle corresponding to the second motor

And the third target joint angle corresponding to the third motor

In order to perform the iteration target joint angle of the Kth iteration, λ is the iteration step coefficient, and Δθ ^(k) is the iteration joint angle error.

(32.10) Determine whether the iterative joint angle error is less than the threshold. When the iterative joint angle error is less than or equal to the threshold, stop the iteration and output

In this way, the Newton iterative algorithm is used to determine the target joint angles corresponding to the first motor, the second motor and the third motor; when the iterative joint angle error is greater than the threshold, steps 32.3-32.10 are repeated until the iterative joint angle error is less than or When equal to the threshold, output

The target joint angle θ _tar1 of the first motor in the _middle .

In practical applications, because the target end attitude changes smoothly and the control period is short (microsecond level), the iterative convergence speed is fast. Normally, only one iteration is performed in each control cycle to obtain the target joint angle corresponding to the first motor.

S33: Determine the target joint angle as a single-axis control component.

After the target joint angle is obtained, the target joint angle can be determined as a single-axis control component, so that the first bracket can be closed-loop controlled according to the target joint angle, as shown in Figure 7, after the target joint angle θ _{tar1 is obtained} , The target joint angle θ _tar1 can be input to the position loop controller C _p , so that the position information d corresponding to the target joint angle θ _tar1 can be obtained, and then the controlled object P (first motor) can be performed using the position information d _Through the control, the measured joint angle θ ₁ corresponding to the first motor can be obtained, and then the measured joint angle θ ₁ and the target joint angle θ _tar1 are used to control the first motor again, so as to realize the use of the target joint angle through the first motor. The first bracket performs closed-loop control.

Obtaining the single-axis control component in the above manner effectively guarantees the accuracy and reliability of the acquisition of the single-axis control component, thereby improving the stability and reliability of the control of the first bracket based on the single-axis control component.

Figure 8 is a schematic diagram of a flow chart for calculating a dual-axis control component based on the target end pose and the measured end pose provided by an embodiment of the present invention; on the basis of the foregoing embodiment, with continued reference to Figure 8, the present embodiment is The specific implementation of the calculation of the dual-axis control component and the measurement of the terminal posture are not limited, and those skilled in the art can set it according to specific application requirements and design requirements. Preferably, according to the target terminal posture and the measurement terminal posture in this embodiment Calculation of dual-axis control components can include:

S34: Obtain the end angular velocity of the gimbal.

Among them, the angle detection of the end (camera) of the pan-tilt can be performed by an angular velocity sensor, so that the end angular velocity of the pan-tilt can be obtained.

S35: Determine the dual-axis control component according to the target end attitude, the measured end attitude and the end angular velocity.

After the terminal angular velocity is obtained, the target terminal attitude, the measured terminal attitude and the terminal angular velocity can be used to determine the dual-axis control component. Specifically, referring to Figure 9, the dual-axis control component can be determined according to the target terminal attitude, the measured terminal attitude and the terminal angular velocity. Control components can include:

S351: Determine the attitude control error of the PTZ according to the target end attitude and the measured end attitude.

Among them, after obtaining the target end posture and the measurement end posture, the target end posture and the measurement end posture can be compared, so that the attitude control error of the pan/tilt can be determined. For example, the attitude control error can be the difference between the target end attitude and the measured end attitude; or the attitude control error can also be the ratio of the measured end attitude to the target end attitude; or the attitude control error can also be (target end attitude -Measuring the ratio of the end posture of the target) to the end posture of the target; specifically, those skilled in the art can use different methods to determine the attitude control error of the PTZ according to different design requirements, which will not be repeated here.

S352: Determine the dual-axis control component according to the attitude control error and the terminal angular velocity.

After the attitude control error is obtained, the attitude control error and the end angular velocity can be analyzed and processed, and the dual-axis control component can be determined according to the analysis and processing results. Specifically, referring to FIG. 10, determining the dual-axis control component according to the attitude control error and the terminal angular velocity in this embodiment may include:

S3521: For the attitude control error and the end angular velocity, remove the components related to the first support from the attitude control error and the end angular velocity, and generate the local attitude control error and the local end angular velocity related to the second support and the third support.

Specifically, referring to FIG. 11, for the attitude control error and the end angular velocity, the components related to the first support in the attitude control error and the end angular velocity are removed, and the local attitude control errors related to the second support and the third support are generated. The local end angular velocity can include:

S35211: Map the attitude control error and the end angular velocity to the joint angle space, and obtain the joint angle control error and the joint angular velocity corresponding to the first motor, the second motor, and the third motor.

S35212: For joint angle control error and joint angular velocity, set the joint angle control error and joint angular velocity on the axis of the first motor to zero to obtain the local joints on the axis of the second motor and the axis of the third motor Angle control error and local joint angular velocity.

S35213: Map the local joint angle control error and the local joint angular velocity back to the body coordinate system to obtain the local attitude control error and the local end angular velocity related to the second bracket and the third bracket.

Among them, when the pan/tilt is located in the neighborhood of the singular point, in order to accurately control the posture of the second bracket and the third bracket, the movement of the first bracket needs to be decoupled from the movement of the second bracket and the third bracket. If the movement of the first bracket, the movement of the second bracket and the movement of the third bracket are regarded as three-dimensional movement, the movement of the second bracket and the movement of the third bracket need to be decoupled from the three-dimensional movement. Specifically, from the Jacobian inverse matrix J(θ) ^-1 , the attitude control error δR and the end angular velocity ω _{b are respectively} mapped to the joint angle space to obtain the joint angle control error θ _e and the joint angular velocity

θ _e ＝J(θ) ^-1 δR

For the first bracket, the joint angle control error θ _e and the joint angular velocity need to be

Joint angle control error in the direction of the motor shaft of the first motor

And joint angular velocity

Set to zero to obtain the local joint angle control error in the axial direction of the second motor and the axial direction of the third motor

And local joint angular velocity

which is:

among them,

Then, using the Jacobian matrix J(θ), the local joint angle control error

And local joint angular velocity

Mapping back to the body coordinate system, so as to obtain the local attitude control errors related to the second bracket and the third bracket

And local end angular velocity

Among them, for the second bracket and the third bracket, the structure can be regarded as a two-link structure, and the three-dimensional attitude control also becomes a two-dimensional attitude control. For the above-mentioned two-link structure, Jacobian matrix

Also reduced to two-dimensional, there is no singularity:

At this time, when using the local attitude control error

And local end angular velocity

When controlling the second bracket and the third bracket, the position loop input is the attitude control error after decoupling

The velocity loop feedback is the body angular velocity after decoupling

And, the mapping relationship from the body coordinate system to the joint angle space is changed to a two-dimensional Jacobian inverse matrix

The local attitude control error and the local end angular velocity are obtained through the above method, which effectively realizes the decoupling of the movement of the first bracket, the movement of the second bracket, and the movement of the third bracket, so as to obtain the connection between the second bracket and the third bracket. The local attitude control error and the local terminal angular velocity related to the support further improve the stability and reliability of the attitude control of the movement of the second support and the third support.

S3522: Determine the dual-axis control component according to the local attitude control error and the local end angular velocity.

After obtaining the local attitude control error and the local terminal angular velocity, the biaxial control component can be determined according to the local attitude control error and the local terminal angular velocity. Specifically, one possible way is to determine the local attitude control error and the local terminal angular velocity. It is a dual-axis control component; alternatively, the local attitude control error and local end angular velocity can be analyzed and processed, and the dual-axis control component can be determined according to the analysis and processing results.

Among them, when the local attitude control error and the local end angular velocity are directly determined as the dual-axis control components, the second support and the third support can be controlled according to the local attitude control error and the local end angular velocity. Referring to FIG. 12, the control of the second bracket and the third bracket according to the dual-axis control component at this time may include the following processes: (1) After acquiring the target end (camera) attitude R _tar and measuring (fusion) end after (camera) pose R _eb, can be obtained according to the target posture terminal R _tar and R _eb posture measuring tip attitude control error δR, then for attitude control error δR, obtain the local attitude control error

Local attitude control error

Input to the position loop controller C _p to obtain the target end angular velocity, and map the target end angular velocity to the joint angular space through the Jacobian inverse matrix to obtain the target joint angular velocity;

(2) Obtain the measured end angular velocity ω _b , and then perform inverse kinematic decoupling (Kinematic decoupling) on the measured end angular velocity ω _b to obtain the local end angular velocity corresponding to the second motor and the third motor

Map the target end angular velocity to the joint angular space through the Jacobian inverse matrix to obtain the measured joint angular velocity;

(3) Calculate the difference between the target joint angular velocity and the measured joint angular velocity, and then input the difference to the speed loop controller C _v , so as to obtain the control object P (the second motor and the third motor) ) To control the torque, so as to realize the closed-loop control of the second bracket and the third bracket through the second motor and the third motor by using the local attitude control error and the local terminal angular velocity.

It should be noted that the order of execution between steps S34-S35 and steps S31-S33 in this embodiment is not limited to the order shown by the serial number, that is, steps S34-S35 can also be executed before steps S31-S33. Alternatively, steps S34-S35 can also be executed simultaneously with steps S31-S33.

The two-axis control component (that is, the local attitude control error

And local end angular velocity

), which effectively guarantees the accuracy and reliability of the acquisition of the dual-axis control component, thereby improving the stability and reliability of the control of the movement posture of the second bracket and the third bracket based on the dual-axis control component.

Figure 14 is a schematic flow chart of another method for controlling a pan/tilt head provided by an embodiment of the present invention; on the basis of the above-mentioned embodiment, referring to FIG. 14, after determining that the pan/tilt head is located outside the neighborhood of a singular point, in this embodiment The method can also include:

S201: Calculate the three-axis control component according to the target end posture of the load and the measured end posture, where the three-axis control component is related to the first support, the second support, and the third support.

S202: Control the first support, the second support and the third support according to the three-axis control components.

Specifically, when the gimbal is located outside the neighborhood of the singular point, the attitude control of the gimbal will not affect the stability of the gimbal control due to the neighborhood of the singular point. Therefore, the end attitude of the target and the measurement end attitude are obtained. After that, the first bracket, the second bracket, and the third bracket can be controlled by the aforementioned three-axis attitude closed-loop controller. Specifically, referring to FIG. 1, the first bracket and the second bracket are controlled according to the three-axis control components. Controlling with the third bracket can include the following processes:

After (1) terminal (camera) pose R _eb in access to the target terminal (the camera) pose R _tar and measuring (fusion) can be obtained pose the target terminal posture R _tar and measuring tip attitude R _eb control error [delta] R, and will pose The control error δR is input to the position loop controller C _p to obtain the target end angular velocity, and the target end angular velocity is mapped to the joint angular space through the Jacobian inverse matrix to obtain the target joint angular velocity;

(2) Obtain the measured end angular velocity ω _b , and then use the Jacobian inverse matrix to map the measured end angular velocity ω _b to the joint angular space to obtain the measured joint angular velocity

(3) Calculate the difference between the target joint angular velocity and the measured joint angular velocity, and then input the difference to the speed loop controller C _v , so as to obtain the control object P (first motor, second motor And the third motor) to control the torque, and then the first motor, the second motor and the third motor are used to drive the first support, and the second support and the third support to perform three-axis closed-loop control, which effectively ensures the PTZ attitude is precisely controlled.

Fig. 15 is a schematic flow chart of yet another method for controlling a pan/tilt head provided by an embodiment of the present invention; on the basis of any of the above embodiments, referring to Fig. 15, the method in this embodiment may further include:

S301: If the pan/tilt is located in the neighborhood of the singular point at the current moment and was outside the neighborhood of the singular point at the previous moment; or, if the pan/tilt is located outside the neighborhood of the singular point at the current moment and was located in the neighborhood of the singular point at the previous moment, then Acquire the first driving signal of the pan/tilt at the previous moment and the second driving signal of the current moment.

For ease of description, the state where the pan/tilt is located in the neighborhood of the singular point is called the pan/tilt in the singular point control mode, and the state where the pan/tilt is located outside the neighborhood of the singular point is called the pan/tilt in the three-axis control mode; When the pan/tilt is controlled, the pan/tilt can be in different control modes, and the different control modes of the pan/tilt can be switched, for example: the pan/tilt is located in the neighborhood of the singularity at the current moment, and outside the neighborhood of the singularity at the previous moment , That is, the pan/tilt is switched from the three-axis control mode at the last moment to the singular point control mode at the current moment; or, the pan/tilt is located outside the singular point neighborhood at the current moment, and is located in the singular point neighborhood at the previous moment, that is, cloud The station is switched from the singular point neighborhood mode at the previous moment to the three-axis control mode at the current moment.

When the pan-tilt is switched between different control modes, in order to ensure the stability of the pan-tilt and the load on the pan-tilt, the first driving signal of the pan-tilt at the previous moment and the second driving signal at the current moment can be obtained. The driving signal, where the first driving signal and the second driving signal can be in any of the following forms: control torque, rotational speed signal, voltage signal, current signal, and so on.

S302: Determine at least one smooth transition signal according to the first driving signal and the second driving signal.

After the first drive signal and the second drive signal are acquired, the first drive signal and the second drive signal can be analyzed and processed, so that at least one smooth transition signal can be determined. Specifically, referring to FIG. The determination of at least one smooth transition signal by a driving signal and a second driving signal may include:

S3021: Obtain a weighting coefficient corresponding to the first driving signal.

Wherein, referring to FIG. 17, obtaining the weighting coefficient corresponding to the first driving signal may include:

S30211: Acquire the preset switching time and the switching time for performing the switching operation.

Wherein, the switching time is the total time required for the pan/tilt to perform the control mode switching operation, and the switching time may be specified by the user or pre-configured by the user. The switching time refers to the time that the pan/tilt head performs the control mode switching operation. For example: the switching time is 5min and the switching start time is 12:00, then the switching end time 12:05 corresponding to the switching start time 12:00 can be determined according to the switching time 5min, and the switching time is the switching start time 12: Either time between 00 and the switching end time 12:05.

S30212: Determine the weighting coefficient according to the switching time and the switching moment.

Among them, after the handover time and handover time are obtained, the following formula can be used to determine the weighting coefficient:

Among them, μ is the weighting coefficient, t ₀ is the switching time, and t is the switching time.

It can be seen from the above formula that the weighting coefficient and the switching time meet a linear relationship, and as the switching time changes continuously, the weighting coefficient will also change. It should be noted that the relationship between the weighting coefficient and the switching time and the switching time in this embodiment is not limited to the above-exemplified formulas, and those skilled in the art can also according to different application scenarios, different control parameters and operating conditions, The correspondence between the weighting coefficient and the switching time is determined to be other linear or non-linear mapping relations, which will not be repeated here.

S3022: Determine at least one smooth transition signal by using the weighting coefficient, the first driving signal and the second driving signal.

After obtaining the weighting coefficient, the first driving signal, and the second driving signal, the following formula may be used to determine at least one smooth transition signal:

T=μT _former +(1-μ)T _latter

Among them, T is the smooth transition signal, μ is the weighting coefficient, T _former is the first driving signal, and T _latter is the second driving signal.

S303: Drive the pan/tilt to move based on the smooth transition signal.

After the smooth transition signal is obtained, the pan/tilt can be driven to move based on the smooth transition signal. Specifically, the pan/tilt can be adjusted from the first drive signal and the smooth transition signal to the second drive signal. It should be noted that when driving the cloud During the movement of the platform, the first drive signal and the second drive signal change in real time, and the drive signal during the switching transition period is determined by the first drive signal and the second drive signal together; During the mode switching, the movement of the pan/tilt can be smoothly transitioned, thereby ensuring the stability and reliability of the pan/tilt.

Through the above process, the smooth processing of the gimbal switching back and forth between the three-axis control mode and the singular point control mode is effectively realized, so that the gimbal has no jitter during the switching process, thus ensuring the stability and reliability of the load work. It also ensures the stability and reliability of the pan-tilt work, and further improves the practicability of the method.

For specific applications, referring to FIG. 18, this application embodiment provides a pan/tilt control method. The pan/tilt control method can be used to control the first bracket and the second bracket when the pan/tilt is located in the neighborhood of the singular point. The first motor, the second motor and the third motor controlled by the support and the third support are decoupled into a first motor and a biaxial stabilizer (including: a second motor for controlling the second support and a Correspondingly, the three-axis attitude closed-loop controller for controlling the first motor, the second motor and the third motor can also be decoupled into two controllers.

Among them, the first controller is a joint angle closed loop controller for controlling the first motor. Specifically, when using the joint angle closed-loop controller to control the first motor, it is necessary to first solve it through inverse kinematics to calculate the target joint angle corresponding to the target end posture, and then use the target joint angle of the first motor and the measurement of the angle sensor The joint angle performs closed-loop control of the joint angle of the first motor. For a specific implementation manner, please refer to the content of the foregoing embodiment, which will not be repeated here.

The other controller is a dual-axis attitude closed-loop controller for controlling the second motor and the third motor. When using a dual-axis attitude closed-loop controller to control the second motor and the third motor, firstly, it is necessary to separate the attitude control error and the angular velocity component in the direction of the first motor, and keep the attitude control error and angular velocity in the second motor and The component in the third motor direction. At this time, the structure of the second motor and the third motor can be equivalent to a two-axis stabilizer, thereby reducing the dimension of the Jacobian matrix to two dimensions, solving the problem of the singularity of the Jacobian matrix. The position loop-speed loop posture closed-loop controller of the dimension is used to control the second motor and the third motor. For the specific implementation manner, please refer to the statement content of the foregoing embodiment, which will not be repeated here.

Specifically, the PTZ control method includes the following steps:

Step1: Perform singularity judgment for the gimbal, obtain the joint angle of the second motor on the gimbal, and judge the control mode of the gimbal according to the joint angle of the second motor.

step2: When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, determine that the gimbal is in singular point control mode; if the joint angle of the second motor is not within the angle range corresponding to the singular point neighborhood , It is determined that the pan/tilt is in three-axis control mode.

step31: When the pan/tilt is in the three-axis control mode, the three-axis control value used to control the first, second and third supports can be obtained. According to the three-axis control value, the first motor and the second The second motor and the third motor control the first support, the second support and the third support.

step32: When the gimbal is in the singular point control mode, calculate the target joint angles of the three motors corresponding to the target end posture through inverse kinematics, and obtain the target joint angle of the first motor from the target joint angle; at the same time; , Decoupling the movement of the first motor from the movement of the second motor and the third motor to obtain the local attitude control error and the local terminal angular velocity for controlling the second motor and the third motor.

Step4: According to the target joint angle, the first bracket is driven by the first motor for closed-loop control; according to the local attitude control error and the local end angular velocity, the second motor and the third motor are used to drive the second bracket and the third bracket for closed-loop control.

In addition, in the above process of controlling the PTZ, the method in this embodiment may further include:

Step11: Detect whether the control mode of the pan/tilt has been switched, and when it is determined that the control mode of the pan/tilt is switched, the switching process of the control mode of the pan/tilt can be smoothly processed.

Controlling the gimbal through the above-mentioned gimbal control method not only expands the range of gimbal attitude control; moreover, it can ensure the stable performance of the gimbal in the neighborhood of the singularity; specifically, it can make the gimbal under different motion conditions Down (such as pushing the rocker, turning the handle and pushing where to stop, etc.), the movement decoupling is realized, and the stability and reliability of the pan/tilt and load are further improved.

Figure 19 is a schematic structural diagram of a pan/tilt control device provided by an embodiment of the present invention; referring to FIG. 19, this embodiment provides a pan/tilt control device that can perform the above-mentioned pan/tilt control The method, wherein the pan-tilt at least includes a first support, a second support, and a third support for connecting a load, which are sequentially connected; specifically, the pan-tilt control device includes:

The detection module 11 is used to detect whether the pan-tilt is located in a preset singularity neighborhood;

The acquiring module 12 is used to acquire the target end attitude and the measurement end attitude of the pan/tilt when the pan/tilt is located in the neighborhood of the singularity;

The calculation module 13 is used to calculate the single-axis control component and the dual-axis control component according to the target end attitude and the measured end attitude; wherein the single-axis control component is related to the first support, and the dual-axis control component is related to the second support and the third support ；

The control module 14 is used to control the first support according to the single-axis control component, and to control the second support and the third support according to the dual-axis control component.

It should be noted that the device shown in FIG. 19 can also execute the methods of the embodiments shown in FIG. 1 to FIG. 17. For parts that are not described in detail in this embodiment, please refer to the related descriptions of the embodiments shown in FIG. 1 to FIG. 17. For the implementation process and technical effects of this technical solution, refer to the description in the embodiment shown in FIG. 1 to FIG. 17, and will not be repeated here.

In a possible design, the structure of the pan/tilt control device shown in FIG. 19 can be implemented as an electronic device, which can be various devices such as a mobile phone, a tablet computer, and a server. As shown in FIG. 20, the electronic device may include: one or more processors 21 and one or more memories 22. Wherein, the memory 22 is used to store a program that supports the electronic device to execute the pan/tilt control method provided in the embodiments shown in FIG. 1 to FIG. 17. The pan/tilt at least includes a first bracket, a second bracket, and a load connected in sequence. The third bracket; wherein the load includes at least one of the following: image acquisition device, heat source detection device, life detection device. The processor 21 is configured to execute a program stored in the memory 22. specific,

The program includes one or more computer instructions, and when one or more computer instructions are executed by the processor 21, the following steps can be implemented:

Run the computer program stored in the memory to realize: detect whether the pan/tilt is located in the neighborhood of the preset singularity; when the pan/tilt is located in the neighborhood of the singularity, obtain the target end attitude and measurement end attitude of the pan/tilt; according to the target end attitude and The single-axis control component and the dual-axis control component are calculated by measuring the end attitude; the single-axis control component is related to the first support, and the dual-axis control component is related to the second support and the third support; the first support is performed according to the single-axis control component Control and control the second bracket and the third bracket according to the dual-axis control component.

Wherein, the structure of the pan/tilt control device may further include a communication interface 23 for the electronic device to communicate with other devices or a communication network.

Further, the pan/tilt head further includes: a first motor, a second motor, and a third motor, one end of the first motor is connected to the first support, and the other end is connected to the carrier, and is used to drive the first support Rotate relative to the carrier; the second motor is arranged on the first support, and is used to drive the second support to rotate relative to the first support; the third motor is arranged on the second support , Used to drive the third bracket to rotate relative to the second bracket; when the processor 21 calculates the single-axis control component according to the target end attitude and the measured end attitude, the processor 21 may be used to execute: Motor, second motor and third motor corresponding to the first measurement joint angle, second measurement joint angle and third measurement joint angle; according to the target end posture, measurement end posture, first measurement joint angle, and second measurement joint angle And the third measuring joint angle, using Newton iterative algorithm to determine the target joint angle corresponding to the first motor; determining the target joint angle as a single-axis control component.

Further, when the processor 21 calculates the dual-axis control component according to the target end posture and the measured end posture, the processor 21 can be used to execute: obtain the end angular velocity of the pan/tilt; determine according to the target end posture, the measured end posture and the end angular velocity Two-axis control component.

Further, when the processor 21 determines the dual-axis control component according to the target end posture, the measured end posture, and the end angular velocity, the processor 21 may be used to execute: determine the attitude control error of the pan/tilt according to the target end posture and the measured end posture; The two-axis control component is determined according to the attitude control error and the end angular velocity.

Further, when the processor 21 determines the dual-axis control component according to the attitude control error and the end angular velocity, the processor 21 can be used to execute: for the attitude control error and the end angular velocity, removing the attitude control error and the end angular velocity and the first bracket The related components generate the local attitude control error and the local end angular velocity related to the second support and the third support; the dual-axis control component is determined according to the local attitude control error and the local end angular velocity.

Further, for the attitude control error and the end angular velocity, the processor 21 removes the components related to the first support from the attitude control error and the end angular velocity, and generates the local attitude control error and the local end angular velocity related to the second support and the third support. When the time, the processor 21 can be used to perform: map the attitude control error and the end angular velocity into the joint angle space, and obtain the joint angle control error and the joint angular velocity corresponding to the first motor, the second motor, and the third motor; Joint angle control error and joint angular velocity, set the joint angle control error and joint angular velocity in the axial direction of the first motor to zero, and obtain the local joint angle control error in the axial direction of the second motor and the third motor. And the local joint angular velocity; the local joint angle control error and the local joint angular velocity are mapped back to the body coordinate system to obtain the local attitude control error and the local end angular velocity related to the second bracket and the third bracket.

Further, when the processor 21 detects whether the pan-tilt is located in the neighborhood of the singular point, the processor 21 may be used to execute: obtain the joint angle of the second motor; When the angle is within the range, it is determined that the pan/tilt is located in the neighborhood of the singular point; or, when the joint angle of the second motor is within the corresponding angle range outside the neighborhood of the singularity, it is determined that the pan/tilt is located outside the neighborhood of the singularity.

Further, after determining that the pan/tilt is located outside the neighborhood of the singular point, the processor 21 may be used to execute: calculate the three-axis control component according to the target end posture of the load and the measured end posture, where the three-axis control component is related to the first support, The second support is related to the third support; the first support, the second support and the third support are controlled according to the three-axis control components.

Further, the processor 21 is further configured to: if the pan/tilt is located in the neighborhood of the singular point at the current moment, it is located outside the neighborhood of the singularity at the previous moment; or, if the pan/tilt is located outside the neighborhood of the singular point at the current moment, at the previous moment When located in the neighborhood of the singular point, obtain the first drive signal of the pan/tilt at the previous moment and the second drive signal at the current moment; determine at least one smooth transition signal according to the first drive signal and the second drive signal; based on the smooth transition The signal drives the pan/tilt to move.

Further, when the processor 21 determines at least one smooth transition signal according to the first driving signal and the second driving signal, the processor 21 may be used to execute: obtain a weighting coefficient corresponding to the first driving signal; use the weighting coefficient, The first drive signal and the second drive signal determine at least one smooth transition signal.

Further, when the processor 21 obtains the weighting coefficient corresponding to the first driving signal, the processor 21 may be used to perform: obtain the preset switching time and the switching time for the switching operation; determine according to the switching time and the switching time Weighting factor.

The device shown in FIG. 20 can execute the method of the embodiment shown in FIG. 1 to FIG. 17. For parts that are not described in detail in this embodiment, refer to the related description of the embodiment shown in FIG. 1 to FIG. 17. For the implementation process and technical effects of this technical solution, refer to the description in the embodiment shown in FIG. 1 to FIG. 17, and will not be repeated here.

In addition, an embodiment of the present invention provides a computer-readable storage medium, the storage medium is a computer-readable storage medium, and the computer-readable storage medium stores program instructions, and the program instructions are used to implement the cloud of FIG. 1 to FIG. Station control method.

21 is a schematic structural diagram of a pan/tilt provided by an embodiment of the present invention; FIG. 22 is a schematic structural diagram of a pan/tilt provided by an embodiment of the present invention. Referring to FIGS. 21-22, this embodiment provides A pan/tilt 100, which includes at least

The first bracket 101, the second bracket 102 and the third bracket 103 for connecting the load 200 connected in sequence;

For the pan-tilt control device corresponding to the above embodiment in FIG. 20, the control device is used to control the first bracket 101, the second bracket 102 and the third bracket 103.

Further, referring to Figures 21-22, the pan/tilt head 100 in this embodiment specifically includes a bracket part for carrying a load 200, and the bracket part is used to mount the load 200 on the handheld carrier 10 to allow the above The handheld carrier 10 carries the above-mentioned load 200 for operation. The load 200 may be an image acquisition device (for example, a photographing device), a heat source detection device, a life detection device, and the like.

The bracket part of the pan/tilt head 100 may include multiple brackets. Specifically, in the illustrated embodiment, the bracket part includes a first bracket 101, a second bracket 102, and a third bracket 103 that are sequentially connected; the first bracket 101 described above. It is used to rotatably connect the handheld carrier 10 so that the handheld pan/tilt 100 can be rotatably connected to the handheld carrier 10 through the first bracket 101. The pan/tilt head 100 also includes a first motor 107, a second motor 108, and a third motor 109. One end of the first motor 101 is connected to the first support 101, and the other end is connected to the carrier 10 for driving the The first support 101 rotates relative to the carrier 10; the second motor 108 is arranged on the first support 101, and is used to drive the second support 102 to rotate relative to the first support 101; The three motors 109 are arranged on the second support 102 and are used to drive the third support 103 to rotate relative to the second support 102. The third bracket 103 is connected to the clamping portion 105, and the clamping portion 105 is used to carry the load 200; it is understood that in other embodiments, the number of brackets included in the bracket portion may be one, two, or four. Or more.

Further, on the basis of the structure of the above-mentioned pan/tilt, the processor is further configured to: obtain the first measured joint angle and the second measured joint angle corresponding to the first motor, the second motor, and the third motor, respectively. Measure the joint angle and the third measurement joint angle; according to the target end posture, the measurement end posture, the first measurement joint angle, the second measurement joint angle and the third measurement joint angle, the Newton iterative algorithm is used to determine the relationship with the first motor The corresponding target joint angle; the target joint angle is determined as the single-axis control component.

Further, the aforementioned handheld carrier 10 is used for the user to hold. In this embodiment, the above-mentioned load 200 is a photographing device. Here, the photographing device may be a camera, a video camera, a mobile phone, etc. for daily photography. Of course, in other embodiments, the aforementioned photographing device may also be in other forms, such as an ultrasonic imaging device, an infrared imaging device, and so on. The user can carry out photographing operations by carrying the load 200 on the handheld platform 100.

Further, the processor is further configured to: obtain the terminal angular velocity of the pan/tilt; and determine the dual-axis control component according to the target terminal posture, the measured terminal posture, and the terminal angular velocity.

Further, the processor is further configured to: determine the attitude control error of the pan/tilt according to the target end attitude and the measured end attitude; and determine the dual-axis control component according to the attitude control error and the end angular velocity.

Further, the processor is further configured to: for the attitude control error and the end angular velocity, remove the components related to the first support in the attitude control error and the end angular velocity, and generate a connection with the second support The local attitude control error and the local end angular velocity related to the third bracket; the two-axis control component is determined according to the local attitude control error and the local end angular velocity.

Further, the processor is further configured to: map the attitude control error and the end angular velocity to the joint angle space to obtain joint angle control errors corresponding to the first motor, the second motor, and the third motor And the joint angular velocity; for the joint angle control error and the joint angular velocity, the joint angle control error and the joint angular velocity in the axial direction of the first motor are set to zero to obtain the axial and the joint angular velocity of the second motor. The local joint angle control error and the local joint angular velocity in the axial direction of the third motor; the local joint angle control error and the local joint angular velocity are mapped back to the body coordinate system to obtain the local related to the second bracket and the third bracket Attitude control error and local end angular velocity.

Further, the processor is further configured to: obtain the joint angle of the second motor; when the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, determine that the pan/tilt is located at the singularity Point neighborhood; or, when the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located outside the singular point neighborhood.

Further, after determining that the pan/tilt is located outside the neighborhood of the singular point, the processor is further configured to calculate a three-axis control component according to the target end attitude and the measured end attitude of the payload, wherein the three-axis control The components are related to the first support, the second support and the third support; the first support, the second support and the third support are controlled according to the three-axis control component.

Further, the processor is further configured to: if the pan/tilt is located in the neighborhood of the singularity at the current moment, it was located outside the neighborhood of the singularity at the previous moment; or, if the pan/tilt is located near the singularity at the current moment Outside the domain, when the previous moment is in the neighborhood of the singularity, the first drive signal of the pan/tilt at the previous moment and the second drive signal of the current moment are acquired; according to the first drive signal and the second drive signal The driving signal determines at least one smooth transition signal; based on the smooth transition signal, the pan/tilt is driven to move.

Further, the processor is further configured to: obtain a weighting coefficient corresponding to the first driving signal; and use the weighting coefficient, the first driving signal, and the second driving signal to determine at least one smooth transition signal.

Further, the processor is further configured to: obtain a preset switching time and a switching time for performing a switching operation; and determine the weighting coefficient according to the switching time and the switching time.

The specific implementation principles and implementation effects of the pan/tilt platform provided in this embodiment are consistent with the pan/tilt platform control device corresponding to FIG. 20. For details, please refer to the foregoing statement content, and will not be repeated here.

FIG. 23 is a schematic structural diagram of a movable platform provided by an embodiment of the present invention; referring to FIG. 23, it can be seen that another aspect of this embodiment provides a movable platform, and the movable platform is at least one of the following: none Human aerial vehicles, unmanned ships, unmanned vehicles; specifically, the movable platform includes:

Body 301;

The power system 302 is arranged on the body 301 and is used to provide power for the movable platform;

In the pan-tilt described in FIGS. 21-22, the pan-tilt 303 is installed on the body 301.

The specific implementation principles and implementation effects of the movable platform provided in this embodiment are consistent with those of the pan-tilt corresponding to Figs. 21-22. For details, please refer to the foregoing statements, and will not be repeated here.

The technical solutions and technical features in each of the above embodiments can be singly or combined in case of conflict with the present invention. As long as they do not exceed the cognitive scope of those skilled in the art, they all belong to the equivalent embodiments within the protection scope of this application. .

In the several embodiments provided by the present invention, it should be understood that the related detection device (for example: IMU) and method disclosed may be implemented in other ways. For example, the embodiments of the remote control device described above are merely illustrative. For example, the division of the modules or units is only a logical function division, and there may be other divisions in actual implementation, such as multiple units or components. Can be combined or integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, remote control devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the various embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solution of the present invention essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , Including several instructions to make a computer processor (processor) execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage media include: U disk, mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM, Random Access Memory), magnetic disks or optical disks and other media that can store program codes.

The above are only the embodiments of the present invention, and do not limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description and drawings of the present invention, or directly or indirectly applied to other related technologies In the same way, all fields are included in the scope of patent protection of the present invention.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: It is still possible to modify the technical solutions described in the foregoing embodiments, or equivalently replace some or all of the technical features; these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention range.

Claims

A pan-tilt control method, characterized in that the pan-tilt at least includes a first support, a second support, and a third support for connecting a load, which are sequentially connected; the method includes:

Detecting whether the PTZ is located in the neighborhood of a preset singularity;

When the pan/tilt is located in the neighborhood of a singular point, acquiring the target end attitude and the measurement end attitude of the pan/tilt;

The single-axis control component and the dual-axis control component are calculated according to the target end attitude and the measured end attitude; wherein the single-axis control component is related to the first support, and the dual-axis control component is related to the second support and The third bracket is related;

The first bracket is controlled according to the single-axis control component, and the second bracket and the third bracket are controlled according to the dual-axis control component.
The method of claim 1, wherein the pan/tilt head further comprises a first motor, a second motor, and a third motor, one end of the first motor is connected to the first support, and the other end is connected to the The carrier is connected to drive the first bracket to rotate relative to the carrier; the second motor is arranged on the first bracket and is used to drive the second bracket to rotate relative to the first bracket; The third motor is arranged on the second support and is used to drive the third support to rotate relative to the second support; the calculation of the single-axis control component according to the target end posture and the measured end posture includes:

Acquiring the first measured joint angle, the second measured joint angle, and the third measured joint angle corresponding to the first motor, the second motor, and the third motor, respectively;

According to the target end posture, the measured end posture, the first measured joint angle, the second measured joint angle, and the third measured joint angle, a Newton iterative algorithm is used to determine the target joint angle corresponding to the first motor;

The target joint angle is determined as the single-axis control component.
The method according to claim 1, wherein calculating a dual-axis control component based on the target end attitude and the measured end attitude comprises:

Obtaining the terminal angular velocity of the pan/tilt;

The dual-axis control component is determined according to the target end posture, the measured end posture, and the end angular velocity.
The method according to claim 3, wherein determining the dual-axis control component according to the target end posture, the measured end posture, and the end angular velocity comprises:

Determining the attitude control error of the PTZ according to the target end attitude and the measurement end attitude;

The two-axis control component is determined according to the attitude control error and the terminal angular velocity.
The method according to claim 4, wherein determining the dual-axis control component according to the attitude control error and the terminal angular velocity comprises:

For the attitude control error and the end angular velocity, remove the components related to the first bracket from the attitude control error and the end angular velocity, and generate the local attitude control error and the local end related to the second bracket and the third bracket Angular velocity

The two-axis control component is determined according to the local attitude control error and the local terminal angular velocity.
The method according to claim 5, characterized in that, for the attitude control error and the end angular velocity, the components related to the first support in the attitude control error and the end angular velocity are removed to generate the second support The local attitude control error and local end angular velocity related to the third bracket include:

Mapping the attitude control error and the end angular velocity to the joint angle space, and obtain the joint angle control error and the joint angular velocity corresponding to the first motor, the second motor, and the third motor;

Regarding the joint angle control error and the joint angular velocity, the joint angle control error and the joint angular velocity in the axial direction of the first motor are set to zero to obtain the axial direction of the second motor and the third motor. Local joint angle control error and local joint angular velocity in the axial direction;

The local joint angle control error and the local joint angular velocity are mapped back to the body coordinate system to obtain the local attitude control error and the local end angular velocity related to the second bracket and the third bracket.
The method according to claim 2, wherein detecting whether the pan-tilt is located in the neighborhood of a singular point comprises:

Acquiring the joint angle of the second motor;

When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located in the singular point neighborhood; or,

When the joint angle of the second motor is within the angle range corresponding to outside the singular point neighborhood, it is determined that the pan/tilt is located outside the singular point neighborhood.
The method according to claim 7, wherein after determining that the pan-tilt is located outside the neighborhood of a singular point, the method further comprises:

Calculating a three-axis control component according to the target end posture and the measured end posture of the load, wherein the three-axis control component is related to the first support, the second support, and the third support;

The first support, the second support and the third support are controlled according to the three-axis control components.
The method according to any one of claims 1-8, wherein the method further comprises:

If the pan/tilt is located in the neighborhood of the singular point at the current moment, it was located outside the neighborhood of the singular point at the previous moment; or, if the pan/tilt is located outside the neighborhood of the singular point at the current moment, when it was located in the neighborhood of the singular point at the previous moment , Acquiring the first drive signal of the pan/tilt at the previous moment and the second drive signal of the pan/tilt at the current moment;

Determining at least one smooth transition signal according to the first driving signal and the second driving signal;

Drive the pan/tilt to move based on the smooth transition signal.
The method according to claim 9, wherein determining at least one smooth transition signal according to the first driving signal and the second driving signal comprises:

Acquiring a weighting coefficient corresponding to the first driving signal;

At least one smooth transition signal is determined using the weighting coefficient, the first driving signal and the second driving signal.
The method according to claim 10, wherein obtaining a weighting coefficient corresponding to the first driving signal comprises:

Obtain the preset switching time and the switching time of the switching operation;

The weighting coefficient is determined according to the switching time and the switching moment.
A control device for a pan-tilt, characterized in that the pan-tilt at least includes a first support, a second support, and a third support for connecting a load, which are sequentially connected; the control device includes:

Memory, used to store computer programs;

The processor is configured to run a computer program stored in the memory to realize: detecting whether the pan/tilt is located in the neighborhood of a preset singularity; when the pan/tilt is located in the neighborhood of the singularity, acquiring the information of the pan/tilt The target end posture and the measurement end posture; the single-axis control component and the dual-axis control component are calculated according to the target end posture and the measured end posture; wherein, the single-axis control component is related to the first bracket, and the dual-axis control The component is related to the second support and the third support; the first support is controlled according to the single-axis control component, and the second support and the third support are controlled according to the dual-axis control component.
The device according to claim 12, wherein the pan/tilt head further comprises: a first motor, a second motor, and a third motor, one end of the first motor is connected to the first bracket, and the other end It is connected with the carrier and is used to drive the first support to rotate relative to the carrier; the second motor is arranged on the first support and is used to drive the second support to rotate relative to the first support; The third motor is arranged on the second support and is used for driving the third support to rotate relative to the second support; the processor is also used for:

Acquiring the first measured joint angle, the second measured joint angle, and the third measured joint angle corresponding to the first motor, the second motor, and the third motor, respectively;

According to the target end posture, the measured end posture, the first measured joint angle, the second measured joint angle, and the third measured joint angle, a Newton iterative algorithm is used to determine the target joint angle corresponding to the first motor;

The target joint angle is determined as the single-axis control component.
The device according to claim 12, wherein the processor is further configured to:

Obtaining the terminal angular velocity of the pan/tilt;

The dual-axis control component is determined according to the target end posture, the measured end posture, and the end angular velocity.
The device according to claim 14, wherein the processor is further configured to:

Determining the attitude control error of the PTZ according to the target end attitude and the measurement end attitude;

The two-axis control component is determined according to the attitude control error and the terminal angular velocity.
The device according to claim 15, wherein the processor is further configured to:

For the attitude control error and the end angular velocity, remove the components related to the first bracket from the attitude control error and the end angular velocity, and generate the local attitude control error and the local end related to the second bracket and the third bracket Angular velocity

The two-axis control component is determined according to the local attitude control error and the local terminal angular velocity.
The device according to claim 16, wherein the processor is further configured to:

Mapping the attitude control error and the end angular velocity to the joint angle space, and obtain the joint angle control error and the joint angular velocity corresponding to the first motor, the second motor, and the third motor;

Regarding the joint angle control error and the joint angular velocity, the joint angle control error and the joint angular velocity in the axial direction of the first motor are set to zero to obtain the axial direction of the second motor and the third motor. Local joint angle control error and local joint angular velocity in the axial direction;

The local joint angle control error and the local joint angular velocity are mapped back to the body coordinate system to obtain the local attitude control error and the local end angular velocity related to the second bracket and the third bracket.
The device according to claim 12, wherein the processor is further configured to:

Acquiring the joint angle of the second motor;

When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located in the singular point neighborhood; or,

When the joint angle of the second motor is within the angle range corresponding to outside the singular point neighborhood, it is determined that the pan/tilt is located outside the singular point neighborhood.
The apparatus according to claim 18, wherein after determining that the pan-tilt is located outside the neighborhood of a singular point, the processor is further configured to:

Calculating a three-axis control component according to the target end posture and the measured end posture of the load, wherein the three-axis control component is related to the first support, the second support, and the third support;

The first support, the second support and the third support are controlled according to the three-axis control components.
The device according to any one of claims 12-19, wherein the processor is further configured to:

If the pan/tilt is located in the neighborhood of the singular point at the current moment, it was located outside the neighborhood of the singular point at the previous moment; or, if the pan/tilt is located outside the neighborhood of the singular point at the current moment, when it was located in the neighborhood of the singular point at the previous moment , Acquiring the first drive signal of the pan/tilt at the previous moment and the second drive signal of the pan/tilt at the current moment;

Determining at least one smooth transition signal according to the first driving signal and the second driving signal;

Drive the pan/tilt to move based on the smooth transition signal.
The device according to claim 20, wherein the processor is further configured to:

Acquiring a weighting coefficient corresponding to the first driving signal;

At least one smooth transition signal is determined using the weighting coefficient, the first driving signal and the second driving signal.
The method according to claim 21, wherein the processor is further configured to:

Obtain the preset switching time and the switching time of the switching operation;

The weighting coefficient is determined according to the switching time and the switching moment.
A pan-tilt, characterized in that it at least includes:

The first support, the second support and the third support for connecting the load connected in sequence;

A control device, the control device includes:

Memory, used to store computer programs;

The processor is configured to run a computer program stored in the memory to realize: detecting whether the pan/tilt is located in the neighborhood of a preset singularity; when the pan/tilt is located in the neighborhood of the singularity, acquiring the information of the pan/tilt The target end posture and the measurement end posture; the single-axis control component and the dual-axis control component are calculated according to the target end posture and the measured end posture; wherein the single-axis control component is related to the first bracket, and the dual-axis control The component is related to the second support and the third support; the first support is controlled according to the single-axis control component, and the second support and the third support are controlled according to the dual-axis control component.
The pan/tilt head according to claim 23, wherein the load comprises at least one of the following:

Image acquisition device, heat source detection device, life detection device.
The pan/tilt head according to claim 24, wherein the pan/tilt head further comprises: a first motor, a second motor and a third motor, one end of the first motor is connected to the first bracket, and the other One end is connected with the carrier and is used to drive the first bracket to rotate relative to the carrier; the second motor is arranged on the first bracket and is used to drive the second bracket to rotate relative to the first bracket; The third motor is arranged on the second support, and is used to drive the third support to rotate relative to the second support; the processor is also used for:

Acquiring the first measured joint angle, the second measured joint angle, and the third measured joint angle corresponding to the first motor, the second motor, and the third motor, respectively;

According to the target end posture, the measured end posture, the first measured joint angle, the second measured joint angle, and the third measured joint angle, a Newton iterative algorithm is used to determine the target joint angle corresponding to the first motor;

The target joint angle is determined as the single-axis control component.
The pan/tilt head according to claim 24, wherein the processor is further configured to:

Obtaining the terminal angular velocity of the pan/tilt;

The dual-axis control component is determined according to the target end posture, the measured end posture, and the end angular velocity.
The pan/tilt head according to claim 26, wherein the processor is further configured to:

Determining the attitude control error of the PTZ according to the target end attitude and the measurement end attitude;

The two-axis control component is determined according to the attitude control error and the terminal angular velocity.
The pan/tilt head according to claim 27, wherein the processor is further configured to:

For the attitude control error and the end angular velocity, remove the components related to the first bracket from the attitude control error and the end angular velocity, and generate the local attitude control error and the local end related to the second bracket and the third bracket Angular velocity

The two-axis control component is determined according to the local attitude control error and the local terminal angular velocity.
The pan-tilt according to claim 28, wherein the processor is further configured to:

Mapping the attitude control error and the end angular velocity to the joint angle space, and obtain the joint angle control error and the joint angular velocity corresponding to the first motor, the second motor, and the third motor;

Regarding the joint angle control error and the joint angular velocity, the joint angle control error and the joint angular velocity in the axial direction of the first motor are set to zero to obtain the axial direction of the second motor and the third motor. Local joint angle control error and local joint angular velocity in the axial direction;

The local joint angle control error and the local joint angular velocity are mapped back to the body coordinate system to obtain the local attitude control error and the local end angular velocity related to the second bracket and the third bracket.
The pan/tilt head according to claim 24, wherein the processor is further configured to:

Acquiring the joint angle of the second motor;

When the joint angle of the second motor is within the angle range corresponding to the singular point neighborhood, it is determined that the pan/tilt is located in the singular point neighborhood; or,

When the joint angle of the second motor is within the angle range corresponding to outside the singular point neighborhood, it is determined that the pan/tilt is located outside the singular point neighborhood.
The pan/tilt head according to claim 30, wherein after determining that the pan/tilt head is located outside the neighborhood of the singularity, the processor is further configured to:

Calculating a three-axis control component according to the target end posture and the measured end posture of the load, wherein the three-axis control component is related to the first support, the second support, and the third support;

The first support, the second support and the third support are controlled according to the three-axis control components.
The pan/tilt head according to any one of claims 24-31, wherein the processor is further configured to:

If the pan/tilt is located in the neighborhood of the singular point at the current moment, it was located outside the neighborhood of the singular point at the previous moment; or, if the pan/tilt is located outside the neighborhood of the singular point at the current moment, when it was located in the neighborhood of the singular point at the previous moment , Acquiring the first drive signal of the pan/tilt at the previous moment and the second drive signal of the pan/tilt at the current moment;

Determining at least one smooth transition signal according to the first driving signal and the second driving signal;

Drive the pan/tilt to move based on the smooth transition signal.
The pan-tilt according to claim 32, wherein the processor is further configured to:

Acquiring a weighting coefficient corresponding to the first driving signal;

At least one smooth transition signal is determined using the weighting coefficient, the first driving signal and the second driving signal.
The pan-tilt according to claim 33, wherein the processor is further configured to:

Obtain the preset switching time and the switching time of the switching operation;

The weighting coefficient is determined according to the switching time and the switching moment.
A movable platform, characterized in that it comprises:

Body

The power system is arranged on the body and used to provide power to the movable platform;

The pan/tilt according to any one of claims 23-34, which is arranged on the body.
A computer-readable storage medium, wherein the storage medium is a computer-readable storage medium, the computer-readable storage medium stores program instructions, and the program instructions are used to implement any one of claims 1-11 PTZ control method described in item.