CN203686509U - Three-degree-of-freedom self-stabilizing platform - Google Patents

Abstract

The utility model discloses a three-degree-of-freedom self-stabilizing platform, which includes a bracket assembly, a motor assembly, a photographing device and a motor control device: the motor control device includes an embedded drive controller, an attitude detection device, and a position detection device. The motor component is an ultrasonic motor, which directly drives the frame component to rotate the shooting device so that the shooting angle can maintain balance when the outside is disturbed. The ultrasonic motor relies on piezoelectric components to operate, and it will not generate electromagnetic interference to the detector installed on the platform. The working principle of the ultrasonic motor is to rely on the friction between the stator and rotor to drive the rotation, and there is a certain pre-tightening force between the stator and rotor. Therefore, the platform can also be locked without power on, thereby playing a self-stabilizing role. The ultrasonic motor itself has the characteristics of low speed and high torque. It does not need a reduction mechanism and can directly drive the platform. Stator-rotor double gyro detection working method organically combines the particularity of the working principle of the ultrasonic motor with the specific requirements of the stable platform, and stabilizes the shooting equipment in real time and dynamically.

Description

Three degrees of freedom self-stabilizing platform

technical field

The utility model relates to a novel three-degree-of-freedom self-stabilizing platform driven by an ultrasonic motor, in particular to a gyro-type self-stabilizing platform with three rotation axes precisely positioned. the

Background technique

In the field of photography, photography or monitoring, during the operation of the carrier aircraft equipped with cameras, such as aircraft, automobiles, ships, robots, etc., due to the high-frequency vibration and low-frequency vibration of the carrier itself or the disturbance of external airflow and uneven ground, it cannot The avoidance will adversely affect the imaging quality of the shooting equipment, and even cause serious distortion of the imaging system, so it is necessary to configure a self-stabilizing platform to carry the camera. In the prior art, most of them use the mechanical topology and circuit drive control system based on the electromagnetic motor, while the servo motor needs gears as the reduction mechanism. Although the DC torque motor can be used in low-speed and high-torque occasions, the motor itself has no self-control. The lock function requires an additional positioning self-locking device, and the torque/mass ratio is small (3~5 times smaller than the equivalent ultrasonic motor), and the electromagnetic motor has the defect of electromagnetic interference. When it is relatively high, it obviously restricts the application range of the self-stabilizing platform, and there are relatively few reports on the self-stabilizing platform based on the driving source of the ultrasonic motor. In order to make up for the above shortcomings, the utility model proposes a three-freedom self-stabilizing platform driven by an ultrasonic motor, and specifically proposes a control strategy integrating the mechanical structure of the platform with the circuit drive system. the

Utility model content

The technical problem to be solved by the utility model is to provide a small volume, simple structure, large torque/mass ratio, good self-locking performance, no electromagnetic interference, and three ultrasonic motors simultaneously control the platform along the X, Y, Z axes. Rotation, the device that maintains the stability of the imaging device. the

In order to solve the above-mentioned technical problems, the three-degree-of-freedom self-stabilizing platform used in the utility model: a three-degree-of-freedom self-stabilizing platform, including a first support, a second support, a third support and a fourth support, the first ultrasonic motor, the second Two ultrasonic motors, a third ultrasonic motor, a first connecting shaft, a first rolling bearing, a second rolling bearing and a second connecting shaft, wherein, the first connecting shaft is connected to the fourth bracket through a connecting plate at one end thereof, and the other end The support and positioning of the first rolling bearing is connected with the second support, the output shaft at one end of the first ultrasonic motor is connected with the fourth support, and the output shaft at one end of the second ultrasonic motor is connected with the first support. One end of the two connecting shafts is connected, the output shaft at one end of the third ultrasonic motor is connected to the second support, and the other end of the second connecting shaft is connected to the fourth support through the support positioning of the second rolling bearing;

The third ultrasonic motor drives the second support and the components connected to the second support to rotate around the Z axis through the output shaft at one end, and the first ultrasonic motor drives the fourth support and the components connected to the fourth support to rotate around the X axis through the output shaft at one end. The shaft rotates, and the second ultrasonic motor drives the second connecting shaft and the components connected to the second connecting shaft to rotate around the Y axis through an output shaft at one end; a shooting device is installed on the first bracket;

The position detection devices are respectively a first position detection device, a second position detection device and a third position detection device, wherein the first position detection device is installed on the cover of the first rolling bearing and connected to one end of the first connecting shaft , the second position detection device is installed on the shell of the second ultrasonic motor and connected to the output shaft at one end of the second ultrasonic motor, the third position detection device is installed on the third bracket and connected to the third ultrasonic motor One end of the motor is connected to the output shaft;

The posture detection devices are respectively a first posture detection device and a second posture detection device, wherein the first posture detection device is bonded to the first bracket, and the second posture detection device is bonded to the fourth bracket superior;

It also includes a motor control device, the motor control device is an embedded controller; the first posture detection device is responsible for providing external interference signals, including the rotation changes along the X axis, Y axis, and Z axis respectively, and then through The microcomputer communication interface transmits the signal to the embedded controller; the second attitude detection device is responsible for providing the speed difference driving the stable platform, including the rotation variation along the X axis, Y axis, and Z axis respectively, and then through the circuit interface The module transmits the signal to the embedded controller; the motor control system with the embedded controller as the core judges the external disturbance state and the working state of the stable platform according to the output information of the first attitude detection device and the second attitude detection device. The drive interface and the power module respectively control the start and stop, forward and reverse, and rotation speed of the first ultrasonic motor, the second ultrasonic motor, and the third ultrasonic motor, so as to compensate for the external disturbance and deflection displacement of the shooting equipment. The first position detection device, the second The second position detection device, the third position detection device transmits the measured speed and forward and reverse signals of each ultrasonic motor to the motor control system based on the embedded controller as the core through the peripheral interface circuit. The rotation displacement signal sends out the drive control signal again to correct each ultrasonic motor, so as to achieve the purpose of closed-loop feedback control.

Further, one end of the first bracket is connected with the tail end flange of the first connecting shaft; the first ultrasonic motor is installed on the mounting plate of the second bracket and fixed with bolts; the first The second ultrasonic motor is installed on the fourth bracket mounting plate and fixed with bolts, and the third ultrasonic motor is installed on the third bracket mounting plate and fixed with bolts. the

Further, the photographing device is an imaging sensor.

Further, the motor control device is a DSP microcontroller or other embedded microcontrollers. the

Further, the attitude detection device is a gyroscope or other attitude detection sensors. the

Further, the position detection device is a rotary encoder or other grating measurement sensors. the

Beneficial effects : In the present invention, the motor control device adopts a single-chip embedded microprocessor (such as DSP, ARM single-chip microcomputer) as the core motor drive control system, there is no synchronization problem, the control accuracy is higher, and it is more conducive to the integration of the drive circuit , miniaturization, combined with program control algorithm and hardware circuit, convenient real-time linkage control of the entire self-stabilizing platform.

The platform adopts the working mode of double attitude detection device detection, that is, the attitude detection device is installed at the first bracket and the fourth bracket, and the attitude detection device at the first bracket is responsible for providing the direction signal of external interference, and the attitude at the fourth bracket is responsible for providing the direction signal of external interference. The detection device is responsible for providing the speed difference driving the stable platform. At this time, it is convenient to judge the state of external interference and the working state of the stable platform according to the output information of the attitude detection devices at the first bracket and the fourth bracket, thereby adjusting the control mode. the

The self-stabilizing platform is directly driven by an ultrasonic motor. The basic principle is: the platform runs at a given angular velocity in the inertial space. When the platform is disturbed by the outside world, the angular velocity of the platform changes. The driving frequency changes the output of the ultrasonic motor until the platform output speed error is zero. the

Description of drawings

Figure 1 is a perspective view of a three-degree-of-freedom self-stabilizing platform. the

Figure 2 is a top view of the three-degree-of-freedom self-stabilizing platform. the

Figure 3 is the ultrasonic motor driven stable platform of the dual attitude detection device. the

Figure 4 is the working principle of the ultrasonic motor-driven stable platform of the dual attitude detection device. the

The reference signs are as follows: 1, the first ultrasonic motor; 2, the shooting equipment; 3, the first support; 4, the first attitude detection device; 5, the second rolling bearing; 6, the second attitude detection device; 7, the first connection Shaft; 8. The first rolling bearing cover; 9. The first rolling bearing; 10. The first position detection device; 11. The second position detection device; 12. The second ultrasonic motor; 13. The second support; 14. The third ultrasonic motor ; 15, the third support; 16, the third position detection device; 17, the fourth support; 18, the second connecting shaft;

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment, the utility model is described in further detail. the

In the three-degree-of-freedom self-stabilizing platform shown in Figures 1 and 2, the shooting device 2 is installed on the first support 3, and the first support 3 is connected with the connecting shaft 18; , the second ultrasonic motor 12 is installed on the fourth bracket 17, the third ultrasonic motor 14 is installed on the third bracket 15; the first position detection device 10 is installed on the rolling bearing cover 8 and connected with one end of the connecting shaft 7, the second The position detection device 11 is installed on the shell of the second ultrasonic motor 12 and is connected with an output shaft of one end of the second ultrasonic motor 12, and the third position detection device 16 is installed on the third bracket 15 and connected with one end of the third ultrasonic motor 14. The output shafts are connected; the first attitude detection device 4 is installed on the first support 3, and the second attitude detection device 6 is installed on the fourth support 17; the first connecting shaft 7 is connected to the fourth support 17 by its one end connecting plate Together, the other end is connected with the second support 13 through the supporting positioning of the rolling bearing 9, the output shaft of one end of the first ultrasonic motor 1 is connected with the fourth support 17, and the output shaft of one end of the second ultrasonic motor 12 is connected with the connecting shaft 18. One end is connected, the output shaft of one end of the third ultrasonic motor 14 is connected with the second support 13 , and the other end of the connecting shaft 18 is connected with the fourth support 17 through the supporting positioning of the rolling bearing 5 . The third ultrasonic motor 14 drives the second support 13 and the components connected with the second support 13 to rotate around the Z axis through the output shaft at one end, and the first ultrasonic motor 1 drives the fourth support 17 and the fourth support 17 through the output shaft at one end. The connected components rotate around the X axis, and the second ultrasonic motor 12 drives the connecting shaft 18 and the components connected to the second connecting shaft 18 to rotate around the Y axis through an output shaft at one end. the

As shown in Figures 1, 2, and 3: combined with the characteristics of ultrasonic motor drive, this self-stabilizing platform adopts the working mode of double attitude detection device detection, that is, the attitude detection device is installed at the first support 3 and the fourth support 17, wherein The attitude detection device 4 at the first support 3 is responsible for providing the direction signal of external disturbance, and the attitude detection device 6 at the fourth support 17 is responsible for providing the speed difference for driving the stable platform. At this time, it is convenient to judge the state of external interference and the working state of the stable platform according to the output information of the attitude detection devices at the first support 3 and the fourth support 17, so as to adjust the control mode. the

As shown in Figure 4, the self-stabilizing platform is directly driven by an ultrasonic motor. The basic principle is: the platform runs at a given angular velocity in the inertial space. When the platform is disturbed by the outside world, the angular velocity of the platform changes. Speed difference, by adjusting the drive frequency to change the output of the ultrasonic motor until the platform output speed error is zero. the

As shown in Figures 1, 2, 3, and 4: the working mode of the three-degree-of-freedom self-stabilizing platform: the first attitude detection device 4 is responsible for providing external interference signals, including three directions along the X-axis, Y-axis, and Z-axis The amount of rotation change, and then transmit the signal to the embedded controller through the microcomputer communication interface; the second attitude detection device 6 is responsible for providing the speed difference driving the stable platform, including the rotation along the X axis, Y axis, and Z axis respectively Change amount, and then transmit the signal to the embedded controller through the circuit interface module; the motor control system with the embedded controller as the core judges the external disturbance at this time according to the output information of the first posture detection device 4 and the second posture detection device 6 state and the working state of the stable platform, through the drive interface and the power module to control the start and stop, forward and reverse, and rotation speed of the first ultrasonic motor 1, the second ultrasonic motor 12, and the third ultrasonic motor 14, so as to compensate for the external influence on the shooting equipment. Disturbance deflection displacement, the first position detection device 10, the second position detection device 11, and the third position detection device 16 transmit the measured speeds of the ultrasonic motors and forward and reverse signals to the embedded controller based on the peripheral interface circuit. The core motor control system, the motor control system re-sends the driving control signal to each ultrasonic motor for correction according to the collected ultrasonic motor rotation displacement signal, so as to achieve the purpose of closed-loop feedback control, so that the whole platform can better realize the dynamic self-stabilization function. the

Claims (1)

1. A three-degree-of-freedom self-stabilizing platform, characterized in that: it comprises a first support (3), a second support (13), a third support (15) and a fourth support (17), the first ultrasonic motor (1 ), the second ultrasonic motor (12), the third ultrasonic motor (14), the first connecting shaft (7), the first rolling bearing (9), the second rolling bearing (5) and the second connecting shaft (18), wherein, The first connecting shaft (7) is connected to the fourth bracket (17) through a connecting plate at one end thereof, and the other end is connected to the second bracket (13) through the supporting positioning of the first rolling bearing (9), One end output shaft of the first ultrasonic motor (1) is connected to the fourth support (17), one end output shaft of the second ultrasonic motor (12) is connected to one end of the second connecting shaft (18) The output shaft at one end of the third ultrasonic motor (14) is connected with the second bracket (13), and the other end of the second connecting shaft (18) is positioned through the support of the second rolling bearing (5) Connected with the fourth bracket (17); The third ultrasonic motor (14) drives the second bracket (13) and the components connected to the second bracket (13) to rotate around the Z axis through an output shaft at one end, and the first ultrasonic motor (1) drives the fourth ultrasonic motor (1) through an output shaft at one end. The bracket (17) and the components connected to the fourth bracket (17) rotate around the X-axis, and the second ultrasonic motor (12) drives the second connecting shaft (18) through an output shaft at one end and connects with the second connecting shaft (18) The assembly rotates around the Y axis; the shooting device (2) is installed on the first bracket (3); The position detection devices are respectively a first position detection device (10), a second position detection device (11) and a third position detection device (16), wherein the first position detection device (10) is installed on the first rolling bearing (9) and connected to one end of the first connecting shaft (7), the second position detection device (11) is installed on the shell of the second ultrasonic motor (12) and connected to the second ultrasonic motor (12) One end of the output shaft is connected, and the third position detection device (16) is installed on the third bracket (15) and connected with one end of the third ultrasonic motor (14) output shaft; The posture detection devices are respectively a first posture detection device (4) and a second posture detection device (6), wherein the first posture detection device (4) is bonded to the first bracket (3), and the Two posture detection devices (6) are bonded to the fourth bracket (17); It also includes a motor control device, the motor control device is an embedded controller; the first posture detection device (4) is responsible for providing external interference signals, including the amount of rotation change along the X axis, Y axis, and Z axis respectively , and then transmit the signal to the embedded controller through the microcomputer communication interface; the second attitude detection device (6) is responsible for providing the speed difference driving the stable platform, including three directions along the X-axis, Y-axis and Z-axis respectively The amount of rotation change, and then transmit the signal to the embedded controller through the circuit interface module; the motor control system with the embedded controller as the core is based on the output information of the first attitude detection device (4) and the second attitude detection device (6). Judging the state of external interference and the working state of the stable platform at this time, respectively control the start and stop of the first ultrasonic motor (1), the second ultrasonic motor (12), and the third ultrasonic motor (14) through the drive interface and power module. Rotation and rotation speed, to compensate for the external disturbance and deflection displacement of the shooting equipment, the first position detection device (10), the second position detection device (11), and the third position detection device (16) take the measured rotation speed of each ultrasonic motor And the forward and reverse signals are transmitted to the motor control system based on the embedded controller through the peripheral interface circuit. The motor control system sends out the driving control signal to each ultrasonic motor for correction according to the collected ultrasonic motor rotation displacement signal to achieve closed-loop feedback. control purposes. 2. A three-degree-of-freedom self-stabilizing platform according to claim 1, characterized in that: one end of the first support (3) is connected to the tail end flange of the first connecting shaft (7); The first ultrasonic motor (1) is installed on the mounting plate of the second bracket (13) and fixed with bolts; the second ultrasonic motor (12) is installed on the mounting plate of the fourth bracket (17) , and fixed with bolts, the third ultrasonic motor (14) is installed on the mounting plate of the third bracket (15), and fixed with bolts. 3. The self-stabilizing platform according to claim 1, characterized in that: the photographing device (2) is an imaging sensor. 4. The self-stabilizing platform according to claim 1, characterized in that: the motor control device is a drive control system based on a DSP microcontroller or other embedded microcontrollers as the core. 5. The self-stabilizing platform according to claim 1, characterized in that: the attitude detection device is a gyroscope or other attitude detection sensors. 6. The self-stabilizing platform according to claim 1, characterized in that: the position detection device is a rotary encoder or other grating measurement sensors.

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