WO2020237493A1

WO2020237493A1 - Zero calibration method for gimbal and gimbal

Info

Publication number: WO2020237493A1
Application number: PCT/CN2019/088731
Authority: WO
Inventors: 谢文麟; 苏铁
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2019-05-28
Filing date: 2019-05-28
Publication date: 2020-12-03
Also published as: CN111684386A

Abstract

A zero calibration method for a gimbal and a gimbal, the gimbal comprising an accelerometer (5) that is used for detecting the posture of a load mounted on the gimbal, and the zero calibration method for a gimbal comprising: when a gimbal is in a specific state, acquiring the current posture of the gimbal on the basis of an accelerometer (5); determining the offset of a pitch axis joint angle and/or a roll axis joint angle of the gimbal according to the current posture of the gimbal; and determining a pitch axis zero joint angle and/or a roll axis zero joint angle of the gimbal according to the offset of the pitch axis joint angle and/or the roll axis joint angle of the gimbal. The ground gravity direction detected by the accelerometer is used to estimate the offset of the pitch axis joint angle and/or the roll axis joint angle of the gimbal, and compensate for the deviation of a joint angle of a corresponding axis; the offset estimated by using said means has higher accuracy, thereby improving the accuracy of the zero calibration of a joint angle, and preventing the roll axis of the gimbal from tilting, while also solving the problem in which the zero calibration of a gimbal overly relies on the structural accuracy of a fixture.

Description

PTZ zero calibration method and PTZ

Technical field

The invention relates to the field of pan/tilt, in particular to a method for calibrating the zero position of the pan/tilt and the pan/tilt.

Background technique

The existing big gimbal cannot be the same as the small gimbal with structural limits. The zero position of the joint angle of the gimbal can be determined by detecting the mechanical limit point by power-on. The big gimbal generally uses a jig to complete the zero position of the joint angle Calibration. Long-term use of the fixture will cause wear, abrasion and improper operation of the fixture, which will cause the fixture to have a virtual position, resulting in a deviation in the zero calibration, and affecting the accuracy of the zero calibration. If the zero deviation of the joint angle is greater than a certain threshold, the gyro speed mapping to the joint angular velocity calculation Jacobian matrix will be deviated, and the joint angle angle calculated based on the velocity integration method will also deviate, which will eventually cause the user to shoot moving pictures. , If the yaw axis of the pan/tilt is quickly rotated, the roll axis of the pan/tilt will be skewed, resulting in poor shooting quality.

Summary of the invention

The invention provides a method for calibrating the zero position of a pan-tilt and a pan-tilt.

Specifically, the present invention is implemented through the following technical solutions:

According to a first aspect of the present invention, a method for zero calibration of a pan/tilt head is provided, the pan/tilt head includes an accelerometer for detecting the posture of a load mounted on the pan/tilt head; the method includes:

When the pan/tilt is in a specific state, acquiring the current posture of the pan/tilt based on the accelerometer;

Determine the offset of the pitch axis joint angle and/or roll axis joint angle of the pan/tilt according to the current posture of the gimbal;

According to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt, the pitch axis zero joint angle and/or the roll axis zero joint angle of the pan/tilt head are determined.

According to a second aspect of the present invention, there is provided a pan-tilt, the pan-tilt including:

The pitch axis assembly is used to carry loads and can rotate around the pitch axis;

The roll axis assembly is capable of rotating around the roll axis to drive the pitch axis assembly and the load to rotate around the roll axis;

An accelerometer for detecting the posture of the load; and

The processor is electrically connected to the pitch axis assembly, the roll axis assembly, and the accelerometer, respectively, wherein the processor is configured to perform the following operations:

As can be seen from the technical solutions provided by the above embodiments of the present invention, the present invention uses the accelerometer on the pan/tilt to determine the pitch axis joint angle and/or roll axis joint angle offset of the pan/tilt, and then calibrate the corresponding axis according to the offset The zero joint angle, that is, the offset of the pitch axis joint angle and/or the roll axis joint angle of the gimbal is estimated by using the ground gravity direction detected by the accelerometer to compensate for the deviation of the joint angle of the corresponding axis. This method is adopted The estimated offset has a high accuracy, which improves the accuracy of the joint angle zero calibration, prevents the tilt of the pan/tilt roll axis, and also solves the problem that the gimbal zero calibration depends excessively on the accuracy of the fixture structure.

Description of the drawings

In order to explain the technical solutions in the embodiments of the present invention more clearly, the following will briefly introduce the accompanying drawings needed in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

FIG. 1 is a schematic structural diagram of a pan-tilt in an embodiment of the present invention;

Figure 2 is a method flow chart of a method for zero calibration of a pan/tilt in an embodiment of the present invention;

3A is a schematic diagram of the positional relationship between the acceleration of gravity and the pitch axis and the roll axis when there is no zero deviation between the pitch axis joint angle and the roll axis joint angle of the pan/tilt in an embodiment of the present invention;

3B is a schematic diagram of the positional relationship between the acceleration of gravity and the pitch axis and the roll axis when the pitch axis joint angle and the roll axis joint angle of the pan/tilt in an embodiment of the present invention have a zero deviation;

4 is a specific method flow chart of the zero calibration method of the pan/tilt in an embodiment of the present invention;

Fig. 5 is a structural block diagram of a pan-tilt in an embodiment of the present invention.

Reference signs:

1: Pitch axis assembly; 11: Pitch axis arm; 12: Pitch axis motor; 2: Roll axis assembly; 21: Roll axis arm; 22: Roll axis motor; 3: Yaw axis assembly; 4: Bearing part; 5 accelerometer; 6: grip part; 7: processor.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than 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.

It should be understood that, in the case of no conflict, the following embodiments and features in the implementation manners can be combined with each other.

In the embodiment of the present invention, the pan/tilt is configured to be able to rotate around the pitch axis and the roll axis. Optionally, the pan/tilt in this embodiment is configured to be capable of rotating around the pitch axis and the roll axis; optionally, the pan/tilt It is also configured to be able to rotate around the yaw axis, that is, the pan/tilt is configured to be able to rotate around the yaw axis, pitch axis, and roll axis.

Optionally, the pan/tilt is a two-axis pan/tilt, which includes a pitch axis assembly and a roll axis assembly, wherein the pitch axis assembly is used to carry loads and can rotate around the pitch axis to drive the load to rotate around the pitch axis, so that The attitude angle of the pitch axis of the load changes; the roll axis assembly can rotate around the roll axis, driving the pitch axis assembly and the load to rotate around the roll axis, so that the attitude angle of the roll axis of the load changes.

Optionally, the gimbal is a three-axis gimbal, which includes a pitch axis assembly, a roll axis assembly, and a yaw axis assembly. The pitch axis assembly is used to carry loads and can rotate around the pitch axis to drive the load around The rotation of the pitch axis changes the attitude angle of the load's pitch axis; the roll axis assembly can rotate around the roll axis, driving the pitch axis assembly and the load to rotate around the roll axis, so that the attitude angle of the load's roll axis changes; yaw axis assembly It can rotate around the yaw axis, drive the roll axis assembly, the pitch axis assembly and the load to rotate around the yaw axis, so that the attitude angle of the yaw axis of the load changes.

Taking a three-axis pan/tilt head as an example, as shown in FIG. 1, the pitch axis assembly 1 may include a pitch axis shaft arm 11 and a pitch axis motor 12 that can rotate around the pitch axis, and the roll axis assembly 2 may include a roll axis shaft arm 21. And the roll axis motor 22 capable of rotating around the roll axis, the yaw axis assembly 3 may include a yaw axis motor capable of rotating around the yaw axis, wherein one end of the roll axis arm 21 is connected to the rotor of the yaw axis motor , The other end of the roll axis arm 21 is connected to the stator of the roll axis motor 22; one end of the pitch axis arm 11 is connected to the rotor of the roll axis motor 22, and the other end of the pitch axis arm 11 is connected to the pitch axis motor 12, load It is mounted on the rotor of the pitch axis motor 12.

The load may be an imaging sensor, or a carrying part 4, which is used to carry equipment with a photographing function such as a camera. Further, referring to Fig. 1 again, the pan/tilt includes an accelerometer 5, which can be used to detect the attitude of the load. It can be understood that the attitude of the payload is also the attitude of the PTZ. Optionally, the accelerometer 5 is fixed on the load.

The pan/tilt in the embodiment of the present invention may be a handheld pan/tilt or a non-handheld pan/tilt; the pan/tilt may be mounted on a mobile device such as a drone or a vehicle. When the pan/tilt is a hand-held pan/tilt, the pan/tilt further includes a holding part 6 and the yaw axis motor is fixedly connected to the top of the holding part 6.

As shown in FIG. 2, an embodiment of the present invention provides a method for zero calibration of a pan/tilt head. The method may include the following steps:

S201: when the pan/tilt is in a specific state, obtain the current attitude of the pan/tilt based on the accelerometer 5;

In this embodiment, the current attitude of the pan/tilt is the real-time attitude of the payload.

The process of obtaining the current attitude of the gimbal based on the accelerometer 5 specifically includes: obtaining the real-time gravitational acceleration components of the gimbal on the pitch axis and roll axis based on the accelerometer; determining the current attitude angle of the corresponding axis according to the gravitational acceleration component; also That is, the current attitude angle of the pitch axis is determined according to the real-time gravitational acceleration component of the pan/tilt on the pitch axis, and the current attitude angle of the roll axis is determined according to the real-time gravitational acceleration component of the pan/tilt on the roll axis.

As shown in Figure 3A, if there is no zero deviation between the pitch axis joint angle and the roll axis joint angle of the gimbal, the acceleration of gravity is collinear with the pitch axis and orthogonal to the roll axis, and the gimbal is on the pitch axis. The real-time gravitational acceleration component Ax=0, the real-time gravitational acceleration component of the gimbal on the roll axis Ay=g (g is the gravitational acceleration), at this time, the attitude angle of the pitch axis is 0 degrees, and the attitude angle of the roll axis is also As shown in Figure 3B, if the pitch axis joint angle and the roll axis joint angle of the gimbal have zero deviation, the acceleration of gravity is not collinear with the pitch axis, and is not orthogonal to the roll axis, Ax ≠0, and Ay≠0, and Ax=gsinα, Ay=gcosα, the size of α can be determined, and according to α, the current attitude angle of the pitch axis and the current attitude angle of the roll axis can be further determined.

The specific state can be a non-horizontal state or a horizontal state. In this embodiment, the specific state is the horizontal state, which reduces the influence of the non-horizontal state on the zero calibration of the gimbal, thereby improving the accuracy of the zero calibration of the gimbal. Optionally, the specific state includes: the pan/tilt is placed on a horizontal surface, and the pan/tilt is in the attitude centering mode. The horizontal plane can be an absolutely horizontal horizontal plane, which is an ideal horizontal plane. It can be understood that when the angle between the horizontal plane and the horizontal plane is less than the preset angle threshold (such as 0.5 degrees), the horizontal plane can also be considered a horizontal plane. . Placing the gimbal on a horizontal surface will help the gimbal stay in a static state, reduce the calculation amount of the gimbal, and speed up the zero calibration of the gimbal. Of course, if the gimbal is moving at a constant speed, it can also be calibrated to its zero position. Compared with the gimbal at a static state, if the gimbal is moving at a constant speed, the gimbal needs to be calibrated to zero. On the basis of the joint angle of the pitch axis and the joint angle of the roll axis determined by the zero calibration, subtract the joint angle change of the corresponding axis during uniform motion, and then judge whether the joint angle of the corresponding axis has a zero deviation.

In addition, when the gimbal is in the attitude return mode, the attitude angle of each axis of the gimbal is 0 degree, and the joint angle of each axis motor is also 0 degree, thus speeding up the zero calibration. Of course, during the zero calibration of the gimbal, the gimbal may not be in the attitude return mode. The joint angle of the pitch axis and the joint angle of the roll axis determined by the gimbal during the zero calibration are subtracted from the initial value of the corresponding axis. Joint angle, and then judge whether the joint angle of the corresponding axis has zero deviation.

As described above, the specific state may further include: the pan/tilt is in a static state, so as to reduce the amount of calculation of the pan/tilt, thereby speeding up the zero calibration of the pan/tilt.

Optionally, the pan/tilt is triggered to perform zero calibration based on the trigger mode, that is, the pan/tilt may be triggered to perform zero calibration based on user requirements. In this embodiment, the method for zero calibration of the PTZ further includes: after the PTZ is in a specific state, before the current posture of the PTZ is acquired based on the accelerometer 5, detecting the zero calibration trigger signal. The zero calibration trigger signal can be generated in different ways. For example, in some embodiments, the zero calibration trigger signal is sent by an external device. The external device can be a remote control that can control the operation of the pan/tilt, and can communicate with the pan/tilt. Communication control terminals (such as mobile phones, tablet computers, etc.) or other smart devices (such as smart bracelets) that can communicate with the pan/tilt. In some embodiments, the zero calibration trigger signal is generated by the button of the pan/tilt. It is understood that the pan/tilt may also be provided with other types of control parts, and the user generates the zero calibration trigger signal by operating the control part. The control unit is not limited to buttons, but can also be a knob or other types. When the pan/tilt is a handheld pan/tilt, the control unit can be arranged on the grip 6 of the handheld pan/tilt, which is convenient for the user to operate.

Optionally, when the pan-tilt detects that it is in a specific state, it automatically enters the zero calibration procedure of the pan-tilt.

S202: Determine the offset of the pitch axis joint angle and/or roll axis joint angle of the gimbal according to the current attitude of the gimbal;

Optionally, determine the offset of the pitch axis joint angle according to the current attitude of the gimbal, and then determine whether the pitch axis joint angle has zero deviation according to the offset of the pitch axis joint angle; optionally, according to the gimbal Determine the offset of the roll axis joint angle, and then determine whether the roll axis joint angle has zero deviation according to the offset of the roll axis joint angle; optionally, according to the current posture of the pan/tilt, Determine the offset of the pitch axis joint angle and the offset of the roll axis joint angle, and then judge whether the corresponding axis joint angle has zero position according to the offset of the pitch axis joint angle and the offset of the roll axis joint angle deviation.

It can be understood that if the specific state is horizontal, the offset of the pitch axis joint angle is the zero offset of the pitch axis joint angle, and the offset of the roll axis joint angle is the roll axis joint angle. If the specific state is non-horizontal, the offset of the joint angle of the pitch axis and the offset of the joint angle of the roll axis are the offset of the corresponding axis when it is non-zero.

Figure 4 is a specific implementation process of S202. As shown in Figure 4, the specific implementation process of S202 may include:

S401: Determine the current pitch axis joint angle and/or current roll axis joint angle of the gimbal according to the current attitude of the gimbal;

In this embodiment, according to the existing conversion relationship between the attitude angle and the joint angle, the current pitch axis attitude angle is converted into the current pitch axis joint angle, and/or the current roll axis attitude angle is converted into the roll axis Joint angle.

S402: Determine the first offset between the current pitch axis joint angle and the first preset threshold and/or the second offset between the current roll axis joint angle and the second preset threshold;

Normally, before the gimbal is calibrated, the pitch axis zero joint angle and roll axis zero joint angle when the gimbal is in the zero position are all 0 degrees. Therefore, in this embodiment, if the gimbal is performing the first zero calibration, the first preset threshold and the second preset threshold are both 0 degrees; that is, the first offset = the current pitch axis joint angle, The second offset = current roll axis joint angle.

However, in some embodiments, before the gimbal is zero-calibrated, the pitch axis zero joint angle and roll axis zero joint angle when the gimbal is in the zero position are not 0 degrees. During zero calibration, the first preset threshold is the pitch axis zero joint angle, and the second preset threshold is the roll axis zero joint angle; that is, the first offset = current pitch axis joint angle-pan/tilt Before zero calibration, the pitch axis zero joint angle when the gimbal is at the zero position, the second offset = the current roll axis joint angle-the gimbal before zero calibration, the horizontal when the gimbal is at zero Roller zero joint angle.

In addition, if the gimbal is not the first zero calibration, the first preset threshold is the pitch axis zero joint angle of the gimbal determined by the last zero calibration of the gimbal, and the second preset threshold is the nearest The roll axis zero joint angle of the gimbal determined by one zero calibration; that is, the first offset = the current pitch axis joint angle-the tilt axis of the gimbal determined by the last zero calibration of the gimbal Zero joint angle, the second offset = current roll axis joint angle-the gimbal's roll axis zero joint angle determined by the last zero calibration of the gimbal.

S303: If the first offset meets the preset zero deviation condition, determine the offset of the pitch axis joint angle of the pan/tilt according to the first offset, and/or if the second offset meets the preset Set the zero deviation condition, then determine the offset of the roll axis joint angle of the pan/tilt according to the second offset.

The first offset meets the preset zero deviation condition, indicating that the pitch axis joint angle of the gimbal has a zero deviation, and zero compensation is required for the pitch axis joint angle; the second offset meets the preset zero deviation The conditions indicate that there is a zero deviation in the roll axis joint angle of the pan/tilt, and zero compensation is required for the roll axis joint angle.

The zero deviation condition can be set as required. For example, in some embodiments, the first offset satisfying the preset zero deviation condition may include: the absolute value of the first offset is greater than the preset first deviation Shift threshold. Taking the non-first zero calibration of the gimbal as an example, if |the current pitch axis joint angle-the pitch axis zero joint angle of the gimbal determined by the last zero calibration of the gimbal|>the first offset threshold, then It is judged that the pitch axis joint angle of the gimbal has a zero deviation; that is, the current pitch axis joint angle-the pitch axis zero joint angle of the gimbal determined by the last zero calibration of the gimbal> the first offset threshold, Or, when the current pitch axis joint angle-the pitch axis zero joint angle of the gimbal determined during the last zero calibration of the gimbal <the opposite of the first offset threshold, it is judged that the pitch axis joint angle of the gimbal has zero position deviation. In some embodiments, the first offset meeting the preset zero deviation condition may include: the absolute value of the first offset is greater than or equal to the preset first offset threshold.

In some embodiments, the second offset satisfying the preset zero deviation condition may include: the absolute value of the second offset is greater than the preset second offset threshold. Also take the non-first zero calibration of the gimbal as an example, if|the current roll axis joint angle-the gimbal's roll axis zero joint angle determined by the last zero calibration of the gimbal|>second offset Threshold value, it is judged that there is a zero deviation in the roll axis joint angle of the pan/tilt; that is, the current roll axis joint angle-the gimbal's roll axis zero joint angle determined by the last zero calibration of the gimbal> The second offset threshold, or the current roll axis joint angle-the gimbal's roll axis zero joint angle determined by the last zero calibration of the gimbal <the opposite of the second offset threshold, the gimbal is judged There is a zero deviation in the joint angle of the roll axis. In some embodiments, the second offset satisfying the preset zero deviation condition may include: the absolute value of the second offset is greater than or equal to the preset second offset threshold.

Among them, the size of the first offset threshold and the second offset threshold can be set as required. Further, the magnitude of the first offset threshold and the second offset threshold may be equal or not equal. For example, in one embodiment, the first offset threshold=the second offset threshold=0.5 degrees.

When determining the offset of the pitch axis joint angle of the gimbal according to the first offset, optionally, in some embodiments, the first offset is set to the pitch axis joint angle of the gimbal. The offset, that is, the offset of the pitch axis joint angle of the gimbal = the first offset; in some embodiments, the offset of the pitch axis joint angle of the gimbal is based on the first offset and the first offset. The preset empirical value is determined, such as the offset of the pitch axis joint angle of the gimbal = the first offset * the first preset empirical value; it can be understood that the pitch axis joint angle of the gimbal is determined according to the first offset The implementation of the offset of is not limited to the two methods listed above, and other methods can also be used.

When determining the offset of the roll axis joint angle of the pan/tilt according to the second offset, optionally, in some embodiments, the second offset is set to the roll axis joint of the pan/tilt. Angle offset, that is, the offset of the roll axis joint angle of the pan/tilt head = the second offset; in some embodiments, the offset of the roll axis joint angle of the pan/tilt head is based on the second offset The amount and the second preset empirical value are determined, such as the offset of the roll axis joint angle of the pan/tilt = the second offset * the second preset empirical value; it is understandable that the pan/tilt is determined according to the second offset The implementation of the offset of the joint angle of the roll axis is not limited to the two methods listed above, and other methods may also be used.

In some embodiments, the first offset is set to the offset of the pitch axis joint angle of the pan/tilt, and the second offset is set to the offset of the roll axis joint angle of the pan/tilt. .

S203: Determine the pitch axis zero joint angle and/or roll axis zero joint angle of the pan/tilt according to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt.

Optionally, determine the pitch axis zero joint angle of the gimbal according to the offset of the pitch axis joint angle of the gimbal; optionally, determine the pitch axis joint angle of the gimbal according to the offset of the roll axis joint angle of the gimbal. Roll axis zero joint angle; optionally, determine the pitch axis zero joint angle of the gimbal according to the offset of the pitch axis joint angle of the gimbal, and according to the offset of the roll axis joint angle of the gimbal To determine the zero joint angle of the roll axis of the gimbal.

When determining the pitch axis zero joint angle of the gimbal according to the offset of the pitch axis joint angle of the gimbal, optionally, in some embodiments, when the gimbal is re-powered on, the gimbal is obtained Pitch axis joint angle during power-up; determine the pitch axis zero joint angle of the gimbal according to the offset between the pitch axis joint angle when the gimbal is powered on again and the pitch axis joint angle of the gimbal. The method for determining the joint angle of the pitch axis when the gimbal is re-powered is the same as the method for determining the joint angle of the current pitch axis of the gimbal in S301, which will not be repeated here. Further optionally, the pitch axis zero joint angle of the gimbal is the difference between the pitch axis joint angle of the gimbal when the gimbal is powered on again and the pitch axis joint angle of the gimbal, that is, the pitch axis of the gimbal Zero joint angle = the pitch axis joint angle when the gimbal is powered on again-the difference between the offset of the pitch axis joint angle of the gimbal. It can be understood that the calculation method of the pitch axis zero joint angle of the gimbal is not limited to this, and other calculation methods can also be used, for example, the pitch axis zero joint angle of the gimbal = (the pitch axis joint when the gimbal is powered on again The difference between the angle and the offset of the pitch axis joint angle of the gimbal) * the first empirical coefficient.

When determining the gimbal's roll axis zero joint angle according to the offset of the gimbal's roll axis joint angle, optionally, when the gimbal is re-powered on, the roll when the gimbal is re-powered Axis joint angle: Determine the roll axis zero joint angle of the gimbal according to the offset between the roll axis joint angle of the gimbal when the gimbal is re-powered on and the roll axis joint angle of the gimbal. The method of determining the joint angle of the roll axis when the pan/tilt is re-powered is the same as the method of determining the joint angle of the current roll axis of the pan/tilt in S301, which will not be repeated here. Further optionally, the zero joint angle of the roll axis of the gimbal is the difference between the joint angle of the roll axis when the gimbal is re-powered and the offset of the joint angle of the roll axis of the gimbal, that is, the gimbal The zero joint angle of the roll axis = the joint angle of the roll axis when the gimbal is powered on again-the offset of the joint angle of the roll axis of the gimbal. It can be understood that the calculation method of the zero joint angle of the roll axis of the gimbal is not limited to this, and other calculation methods can also be used. For example, the zero joint angle of the roll axis of the gimbal = (the horizontal axis when the gimbal is re-powered). Roller joint angle-the offset of the roll shaft joint angle of the gimbal) * The second empirical coefficient.

In the method for calibrating the zero position of the gimbal in the embodiment of the present invention, the accelerometer 5 on the gimbal is used to determine the offset of the pitch axis joint angle and/or the roll axis joint angle of the gimbal, and then calibrate the corresponding axis according to the offset Zero joint angle, that is, estimate the offset of the pitch axis joint angle and/or roll axis joint angle of the gimbal using the direction of gravity detected by the accelerometer 5, and compensate for the deviation of the joint angle of the corresponding axis. This method is adopted The estimated offset has a high accuracy, which improves the accuracy of the joint angle zero calibration, prevents the tilt of the pan/tilt roll axis, and also solves the problem that the gimbal zero calibration depends excessively on the accuracy of the fixture structure.

Corresponding to the gimbal zero calibration method of the above-mentioned embodiment, in conjunction with FIG. 1 and FIG. 5, an embodiment of the present invention also provides a gimbal. The gimbal may include a pitch axis assembly 1, a roll axis assembly 2, an accelerometer 5 and processor 7. Among them, the pitch axis assembly 1 is used to carry a load and can rotate around the pitch axis; the roll axis assembly 2 can rotate around the roll axis to drive the pitch axis assembly 1 and the load to rotate around the roll axis; accelerometer 5 Used to detect the posture of the load; the processor 7 is electrically connected to the pitch axis assembly 1, the roll axis assembly 2 and the accelerometer 5, respectively. The processor 7 of this embodiment is electrically connected to the pitch axis motor 12, The roll axis motor 22 is electrically connected.

Specifically, the processor 7 is configured to perform the following operations: when the pan/tilt is in a specific state, obtain the current attitude of the pan/tilt based on the accelerometer 5; determine the cloud/tilt based on the current attitude of the pan/tilt The offset of the pitch axis joint angle and/or the roll axis joint angle of the platform; determine the pitch axis of the platform according to the offset of the pitch axis joint angle and/or the roll axis joint angle of the platform Zero joint angle and/or roll axis zero joint angle.

The processor 7 of the embodiment of the present invention can implement the zero calibration method of the pan/tilt head as shown in the embodiments shown in Figs. Repeat it again.

The processor 7 in this embodiment may include one or more, and one or more processors 7 are individually or collectively configured to implement the zero calibration of the pan/tilt head as shown in the embodiments shown in FIGS. 1 and 4 of the present invention. method.

It should be understood that in the embodiment of the present invention, the processor 7 may be a central processing unit (CPU). The processor 7 may also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application-specific integrated circuit (ASIC), field-programmable gate array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor 7 may also be any conventional processor or the like.

Furthermore, the pan/tilt head further includes a yaw axis assembly 3 which is electrically connected to the processor 7, and the yaw axis motor of this embodiment is electrically connected to the processor 7.

In addition, an embodiment of the present invention also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the pan/tilt zero calibration method described in the embodiment corresponding to FIG. 1 of the present invention is implemented. This will not be repeated here.

The computer-readable storage medium may be the internal storage unit of the pan/tilt head described in any of the foregoing embodiments, such as a hard disk or a memory. The computer-readable storage medium may also be an external storage device of the pan-tilt, such as a plug-in hard disk, a smart media card (SMC), an SD card, a flash card (Flash Card), etc. equipped on the device . Further, the computer-readable storage medium may also include both an internal storage unit of the pan-tilt and an external storage device. The computer-readable storage medium is used to store the computer program and other programs and data required by the pan/tilt, and can also be used to temporarily store data that has been output or will be output.

A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing relevant hardware through a computer program. The program can be stored in a computer readable storage medium. During execution, it may include the procedures of the above-mentioned method embodiments. Wherein, the storage medium may be a magnetic disk, an optical disc, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM), etc.

The above-disclosed are only some embodiments of the present invention, which of course cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims

A method for calibrating the zero position of a gimbal, the gimbal includes an accelerometer for detecting the posture of a load carried on the gimbal; the method is characterized in that the method includes:

When the pan/tilt is in a specific state, acquiring the current posture of the pan/tilt based on the accelerometer;

Determining the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt according to the current posture of the gimbal;

According to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt, the pitch axis zero joint angle and/or the roll axis zero joint angle of the pan/tilt head are determined.
The method according to claim 1, wherein the determining the pitch axis joint angle and/or the offset of the roll axis joint angle of the pan/tilt based on the current posture of the pan/tilt includes:

Determine the current pitch axis joint angle and/or current roll axis joint angle of the pan/tilt according to the current posture of the gimbal;

Determining a first offset between the current pitch axis joint angle and a first preset threshold and/or a second offset between the current roll axis joint angle and a second preset threshold;

If the first offset satisfies the preset zero deviation condition, determine the offset of the pitch axis joint angle of the pan/tilt according to the first offset, and/or if the first offset If the second offset satisfies the preset zero deviation condition, the offset of the joint angle of the roll axis of the pan/tilt head is determined according to the second offset.
The method according to claim 2, wherein if the pan-tilt is the first zero calibration, the first preset threshold and the second preset threshold are both zero.
The method according to claim 2, wherein if the pan/tilt is not the first zero calibration, the first preset threshold is the pan/tilt determined by the most recent zero calibration of the pan/tilt The second preset threshold is the zero joint angle of the roll axis of the pan/tilt which is determined by the last zero calibration of the pan/tilt.
The method according to claim 2, wherein the first offset satisfies a preset zero deviation condition, comprising: the absolute value of the first offset is greater than a preset first offset threshold .
The method according to claim 2, wherein the second offset satisfies a preset zero deviation condition, comprising: the absolute value of the second offset is greater than a preset second offset threshold .
The method according to claim 2, wherein the determining the offset of the pitch axis joint angle of the pan/tilt according to the first offset comprises:

Setting the first offset as the offset of the pitch axis joint angle of the pan/tilt; and/or

The determining the offset of the roll axis joint angle of the pan/tilt according to the second offset includes:

The second offset is set as the offset of the joint angle of the roll axis of the pan/tilt.
The method according to claim 2, wherein the pitch axis zero joint angle of the pan/tilt head is determined according to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt head And/or roll axis zero joint angle, including:

When the pan/tilt head is powered on again, acquiring the pitch axis joint angle and/or roll axis joint angle when the pan/tilt head is powered on again;

Determine the pitch axis zero joint angle of the gimbal according to the offset between the pitch axis joint angle of the gimbal when the gimbal is powered on again and the pitch axis joint angle of the gimbal; and/or

The zero joint angle of the roll axis of the pan/tilt head is determined according to the offset between the joint angle of the roll axis of the pan/tilt head when the pan/tilt is re-powered on and the joint angle of the roll axis of the pan/tilt head.
The method according to claim 8, wherein the pitch axis zero joint angle of the gimbal is the deviation of the pitch axis joint angle of the gimbal when the gimbal is re-powered on and the pitch axis joint angle of the gimbal. The difference in the amount of movement.
The method of claim 8, wherein the zero joint angle of the roll axis of the pan/tilt is the joint angle of the roll axis when the pan/tilt is re-powered on and the joint angle of the roll axis of the pan/tilt. The difference of the angular offset.
The method according to claim 1, wherein the specific state comprises:

The pan-tilt is placed on a horizontal surface, and the pan-tilt is in a posture centering mode.
The method according to claim 11, wherein the specific state further comprises:

The pan-tilt is in a static state.
The method according to claim 1, wherein after the pan/tilt is in a specific state, before acquiring the current posture of the pan/tilt based on the accelerometer, the method further comprises:

The zero calibration trigger signal is detected.
The method according to claim 13, wherein the zero calibration trigger signal is sent by an external device, or the zero calibration trigger signal is generated by triggering a button of the pan/tilt head.
The method according to claim 1, wherein the current posture is a real-time posture of the load, and the acquiring the current posture of the pan/tilt based on the accelerometer comprises:

Based on the accelerometer, obtaining real-time gravitational acceleration components of the gimbal on the pitch axis and the roll axis;

According to the gravitational acceleration component, the current attitude angle of the corresponding axis is determined.
A pan-tilt, characterized in that the pan-tilt includes:

The pitch axis assembly is used to carry loads and can rotate around the pitch axis;

The roll axis assembly is capable of rotating around the roll axis to drive the pitch axis assembly and the load to rotate around the roll axis;

An accelerometer for detecting the posture of the load; and

The processor is electrically connected to the pitch axis assembly, the roll axis assembly, and the accelerometer, respectively, wherein the processor is configured to perform the following operations:

When the pan/tilt is in a specific state, acquiring the current posture of the pan/tilt based on the accelerometer;

Determining the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt according to the current posture of the gimbal;

According to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt head, the pitch axis zero joint angle and/or the roll axis zero joint angle of the pan/tilt head are determined.
The pan/tilt head according to claim 16, wherein the processor determines the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt head according to the current attitude of the pan/tilt head When, specifically used for:

Determine the current pitch axis joint angle and/or current roll axis joint angle of the pan/tilt according to the current posture of the gimbal;

Determining a first offset between the current pitch axis joint angle and a first preset threshold and/or a second offset between the current roll axis joint angle and a second preset threshold;

If the first offset satisfies the preset zero deviation condition, determine the offset of the pitch axis joint angle of the pan/tilt according to the first offset, and/or if the first offset If the second offset satisfies the preset zero deviation condition, the offset of the joint angle of the roll axis of the pan/tilt head is determined according to the second offset.
The pan/tilt head according to claim 17, wherein if the pan/tilt head is the first zero calibration, the first preset threshold and the second preset threshold are both zero.
The pan/tilt head according to claim 17, wherein if the pan/tilt head is not zero-calibrated for the first time, the first preset threshold is the cloud determined by the most recent zero-calibration of the pan/tilt. The zero joint angle of the pitch axis of the platform, and the second preset threshold is the zero joint angle of the roll axis of the platform determined by the latest zero calibration of the platform.
The pan/tilt head according to claim 17, wherein the first offset satisfies a preset zero deviation condition, comprising: the absolute value of the first offset is greater than the preset first offset Threshold.
The pan/tilt head according to claim 17, wherein the second offset satisfies a preset zero deviation condition, comprising: the absolute value of the second offset is greater than the preset second offset Threshold.
The pan/tilt head according to claim 17, wherein the processor is specifically configured to: when determining the offset amount of the joint angle of the pitch axis of the pan/tilt head according to the first offset amount:

Setting the first offset as the offset of the pitch axis joint angle of the pan/tilt; and/or

When the processor determines the offset of the joint angle of the roll axis of the pan/tilt according to the second offset, it is specifically configured to:

The second offset is set as the offset of the joint angle of the roll axis of the pan/tilt.
The pan/tilt head according to claim 17, wherein the processor determines the pitch axis of the pan/tilt head according to the offset of the pitch axis joint angle and/or the roll axis joint angle of the pan/tilt head. When the zero joint angle and/or roll axis zero joint angle, it is specifically used for:

When the pan/tilt head is powered on again, acquiring the pitch axis joint angle and/or roll axis joint angle when the pan/tilt head is powered on again;

Determine the pitch axis zero joint angle of the gimbal according to the offset between the pitch axis joint angle of the gimbal when the gimbal is powered on again and the pitch axis joint angle of the gimbal; and/or

The zero joint angle of the roll axis of the pan/tilt head is determined according to the offset between the joint angle of the roll axis of the pan/tilt head when the pan/tilt is re-powered on and the joint angle of the roll axis of the pan/tilt head.
The gimbal according to claim 23, wherein the pitch axis zero joint angle of the gimbal is the joint angle of the pitch axis when the gimbal is re-powered on and the joint angle of the pitch axis of the gimbal. The difference of the offset.
The pan/tilt head according to claim 23, wherein the zero joint angle of the roll axis of the pan/tilt head is the joint angle of the roll axis when the pan/tilt is re-powered and the roll axis of the pan/tilt head. The difference of the offset of the joint angle.
The pan/tilt head according to claim 16, wherein the specific status comprises:

The pan-tilt is placed on a horizontal surface, and the pan-tilt is in a posture centering mode.
The pan/tilt head of claim 26, wherein the specific status further comprises:

The pan-tilt is in a static state.
The pan/tilt head of claim 16, wherein the processor is further configured to: after the pan/tilt head is in a specific state, before acquiring the current attitude of the pan/tilt head based on the accelerometer:

The zero calibration trigger signal is detected.
The pan/tilt head according to claim 28, wherein the zero calibration trigger signal is sent by an external device, or the zero calibration trigger signal is generated by triggering a key of the pan/tilt head.
The pan/tilt head according to claim 16, wherein the current attitude is a real-time attitude of the load, and the processor is specifically configured to: when acquiring the current attitude of the pan/tilt head based on the accelerometer:

Based on the accelerometer, obtain the real-time gravitational acceleration components of the gimbal on the pitch axis and the roll axis;

According to the gravitational acceleration component, the current attitude angle of the corresponding axis is determined.
A computer-readable storage medium having a computer program stored thereon, wherein the program is executed by a processor to implement the steps of the pan/tilt zero calibration method according to any one of claims 1 to 15.