Servo rotary scanning system of three-dimensional holographic imaging

A servo rotary scanning system of three-dimensional holographic imaging may include a servomotor (20) having a first angle sensor (21), a second angle sensor (30), a control component (40), a servo driver (50) and a rotary frame (10), the servo rotary scanning system of three-dimensional holographic imaging is a full-closed loop servo control system, the second angle sensor (30) detects an actual rotating angle of the rotary frame (10) and feeds back a frame feedback signal to the control component (40), an instruction signal in the control component (40) is compared with the frame feedback signal to generate a following error, the first angle sensor (21) detects an output rotating angle of the servomotor (20) and feeds back a motor feedback signal to the servo driver (50), and the servo driver (50) controls the servomotor (20) to rotate according to the following error and the motor feedback signal.

TECHNICAL FIELD

The present disclosure generally relates to the technical field of mechanical transmission and servo control, and more particularly, relates to a servo rotary scanning system of three-dimensional (3D) holographic imaging.

BACKGROUND

Three-dimensional holographic imaging systems have found wide application in the field of security inspection, and have achieved the purpose of covering and inspecting carried foreign matters with no dead angle due to the capability of observing and imaging from multiple viewing angles as compared to the flat-plate imaging system. In order to achieve precise three-dimensional imaging, an object-under-test needs to be covered from multiple angles by adopting cylindrical scanning. Thus, higher requirements have been imposed on the servo rotary scanning system of three-dimensional holographic imaging. During the operation, a rotary frame for transceiving antenna modules needs to rotate within a certain range of angles and it needs to be ensured that the overall deformation or shaking of the rotary frame in the horizontal direction and the radial direction is below a certain threshold. Due to requirements for the imaging speed imposed by the market, the scanning speed of the three-dimensional holographic imaging system during the operation is relatively high, which results in a decreased stability at the start and stop of the scanning. Moreover, to cooperate with the accurate transmitting and receiving of the signal of the transceiving antenna module, it is also needed to ensure that the rotation of the motor and the transceiving of the transceiving antenna module are performed simultaneously at time sequence, and this imposes requirements for the real-time monitoring and the inspection of the servo control system. During the multiple reciprocating scanning processes of the servo control system, the start and end positions of each scanning have to be positioned accurately, a real-time output rotating angle of the motor and an actual rotating angle of the rotary frame should be fed back in time and the time delay of the feedback should satisfy certain requirements. Accordingly, an urgent need exists in the market to develop a servo rotary scanning system of three-dimensional holographic imaging that satisfies the aforesaid technical requirements.

SUMMARY

An objective of the present disclosure is to provide a servo rotary scanning system of three-dimensional holographic imaging, which is intended to solve the technical problem in the three-dimensional holographic imaging system currently available that a higher running speed of the transceiving antenna module causes a decreased stability at the start and stop of the scanning; and meanwhile, the system satisfies requirements for the real-time monitoring and inspection of the servo rotary scanning system, and the precise positioning of the start and end positions of each scanning during the multiple reciprocating scanning processes.

The present disclosure is achieved in the following way: a servo rotary scanning system of three-dimensional holographic imaging comprises:

a rotary frame, being configured to mount transceiving antenna modules;

a servomotor, being configured to drive the rotary frame to rotate, the servomotor having a first angle sensor for detecting an output rotating angle thereof;

a second angle sensor, being disposed on a rotating axis of the rotary frame and being configured to detect an actual rotating angle of the rotary frame;

a control component, being electrically connected with the second angle sensor; and

a servo driver, being configured to control the servomotor to rotate according to the actual rotating angle of the rotary frame and the output rotating angle of the servomotor, the first angle sensor and the control component all being electrically connected with the servo driver.

Further, the rotary frame comprises a first cross arm that is driven by the servomotor to rotate and two carrying arms respectively disposed at two ends of the first cross arm and configured to mount the transceiving antenna modules.

Further, both of the two carrying arms extend along a substantially vertical direction, and a transceiving antenna module is disposed at an inner side of each of the carrying arms.

Further, a rotating axis of the first cross arm is located at a center of the first cross arm.

Further, the servomotor drives the rotary frame to perform reciprocating scanning motion about a rotating axis.

Further, the rotary frame further comprises a second cross arm connected between the two carrying arms, and the first cross arm and the second cross arm are disposed opposite to each other.

Further, the first cross arm, the two carrying arms and the second cross arm are arranged in a rectangular form.

Further, an inner surface of the first cross arm is substantially parallel to an inner surface of the second cross arm.

Further, a line connecting centers of the first cross arm and the second cross arm is the rotating axis of the rotary frame.

Further, the first cross arm, the two carrying arms and the second cross arm are formed into an integral structure or an assembled structure.

Further, the servo rotary scanning system of three-dimensional holographic imaging further comprises a fixing support having an upper mounting arm and a lower mounting arm disposed opposite to each other, and the rotary frame is rotatably mounted between the upper mounting arm and the lower mounting arm.

Further, the servomotor is disposed on the upper mounting arm, the first cross arm is rotatably mounted on the upper mounting arm, the second cross arm is rotatably mounted on the lower mounting arm; or the servomotor is disposed on the lower mounting arm, the first cross arm is rotatably mounted on the lower mounting arm, and the second cross arm is rotatably mounted on the upper mounting arm.

Further, the servomotor and the rotating frame are connected via a reducer.

Further, the control component comprises an upper computer, a first controller configured to receive a scan instruction issued by the upper computer, and a second controller communicatively connected with the first controller and electrically connected with the servo driver.

Further, the servo rotary scanning system of three-dimensional holographic imaging further comprises a rotation direction sensor configured to detect positive and negative rotating orientations of the rotary frame and limit the rotating angle of the rotary frame, and the rotation direction sensor is electrically connected with the second controller.

As compared to the prior art, the present disclosure has the following technical effects: the servo rotary scanning system of three-dimensional holographic imaging may consist of a servomotor having a first angle sensor, a second angle sensor, a control component, a servo driver and a rotary frame. The servo rotary scanning system of three-dimensional holographic imaging is a full-closed loop servo control system, the second angle sensor detects the actual rotating angle of the rotary frame and feeds back a frame feedback signal to the control component, an instruction signal in the control component is compared with the frame feedback signal to generate a following error, the first angle sensor detects an output rotating angle of the servomotor and feeds back a motor feedback signal to the servo driver, and the servo driver controls the servomotor to rotate according to the following error and the motor feedback signal.

The servo rotary scanning system of three-dimensional holographic imaging has a simple structure, a lower cost and a high rotation precision and is easy to be assembled and controlled. The rotary frame can ensure stable start and stop of the scanning even at a higher running speed. To cooperate with the accurate transmitting and receiving of the signal of the transceiving antenna module, the rotation of the servomotor and the transceiving of the transceiving antenna module can be ensured to be performed simultaneously at time sequence, and the requirements for the real-time monitoring and the inspection of the servo control system are satisfied. During the multiple reciprocating scanning processes of the servo control system, the start and end positions of each scanning can be positioned accurately, the real-time output rotating angle of the servomotor and the actual rotating angle of the rotary frame can be fed back in time and the time delay of the feedback satisfies certain requirements.

DETAILED DESCRIPTION

To make objectives, technical solutions and advantages of the present disclosure clearer and easier to be understood, the present disclosure will be further described in detail hereinafter with reference to attached drawings and embodiments. It shall be appreciated that, specific embodiments described herein are only used for explaining the present disclosure and not intended to limit the present disclosure.

Referring toFIG. 1andFIG. 2, a servo rotary scanning system of three-dimensional holographic imaging provided according to a first embodiment of the present disclosure comprises: a rotary frame10that is configured to mount transceiving antenna modules90; a servomotor20that is configured to drive the rotary frame10to rotate, the servomotor20having a first angle sensor21for detecting an output rotating angle thereof; a second angle sensor30that is disposed on a rotating axis of the rotary frame10and configured to detect an actual rotating angle of the rotary frame10; a control component40that is electrically connected with the second angle sensor30; and a servo driver50that is configured to control the servomotor20to rotate according to the actual rotating angle of the rotary frame10and the output rotating angle of the servomotor20, the first angle sensor21and the control component40all being electrically connected with the servo driver50.

The servo rotary scanning system of three-dimensional holographic imaging may consist of the servomotor20having the first angle sensor21, the second angle sensor30, the control component40, the servo driver50and the rotary frame10, the servo rotary scanning system of three-dimensional holographic imaging may be a full-closed loop servo control system, the second angle sensor30may detect the actual rotating angle of the rotary frame10and feed back a frame feedback signal A to the control component40, an instruction signal I in the control component40may be compared with the frame feedback signal A to generate a following error E, the first angle sensor21may detect an output rotating angle of the servomotor20and feed back a motor feedback signal B to the servo driver50, and the servo driver50may control the servomotor20to rotate according to the following error E and the motor feedback signal B.

The servo rotary scanning system of three-dimensional holographic imaging may have a simple structure, a lower cost, a high rotation precision and may be easy to be assembled and controlled. The rotary frame10can ensure stable start and stop of the scanning even at a higher running speed. To cooperate with the accurate transmitting and receiving of the signal of the transceiving antenna module90, the rotation of the servomotor20and the transceiving of the transceiving antenna module90can be ensured to be performed simultaneously at time sequence, and the requirements for the real-time monitoring and the inspection of the servo control system can be satisfied. During the multiple reciprocating scanning processes of the servo control system, the start and end positions of each scanning can be positioned accurately, the real-time output rotating angle of the servomotor20and the actual rotating angle of the rotary frame10can be fed back in time and the time delay of the feedback satisfies certain requirements.

The transceiving antenna module90may comprise several transceiving antenna units arranged in columns. Each of the transceiving antenna units may comprise a transmitting antenna and a receiving antenna disposed adjacent to the transmitting antenna, the radiation transmitted sequentially by the transmitting antennas in all the transceiving antenna units may be irradiated to a to-be-imaged object, and millimeter-waves reflected back from the to-be-imaged object are received sequentially by the receiving antennas corresponding to the transmitting antennas, and thus a predetermined scan area can be scanned. Specifically, the transceiving antenna module90may be a millimeter-wave transceiving antenna module, and the millimeter-waves refer to electromagnetic waves having a frequency of 26 GHz to 300 GHz.

The first angle sensor21may be built in the servomotor20and is configured to detect the output rotating angle of the servomotor20. The second angle sensor30may be mounted at any part of the rotating axis of the rotary frame10, e.g., at the top or the bottom of the rotary frame10, to detect the actual rotating angle of the rotary frame10. Each of the first angle sensor21and the second angle sensor30may be a rotary transformer, an inductosyn, an optical grating, a magnetic grating, an encoder or other angle detecting elements, and it may be selected depending on actual needs.

In the aforesaid full-close loop servo control system, the control component40may be provided with the instruction signal I therein, and the instruction signal I of the control component40may be compared with the frame feedback signal A to generate a following error E. If the following error E exceeds a certain range, an alert signal may be generated, and the servo driver50controls the servomotor20to rotate according to the following error E and the motor feedback signal B. The frame feedback signal A fed by the second angle sensor30back to the control component40may be a position feedback signal, and the motor feedback signal B fed by the first angle sensor21back to the servo driver50may be a position and speed feedback signal. Relevant software algorithms involved in controlling the servomotor20to rotate by the servo driver50according to the following error E and the motor feedback signal B belong to the prior art.

Further, the rotary frame10may comprise a first cross arm11that can be driven by the servomotor20to rotate and two carrying arms12respectively disposed at two ends of the first cross arm11and configured to mount the transceiving antenna module90. The servomotor20may drive the first cross arm11to rotate, the two carrying arms12may be distributed opposite to each other, and an inner side of each of the carrying arms12may be provided with a transceiving antenna module90, two transceiving antenna modules90may form a predetermined scan area therebetween, and the two transceiving antenna modules90may rotate about a same plumb line to scan the predetermined scan area. The servomotor20may drive the rotary frame10to perform half-circular reciprocating scanning motion, thereby achieving cylindrical rotary scanning. When a person stands within the predetermined scan area, three-dimensional scanning of the human body can be accomplished simply by scanning for one time. Both of the two carrying arms12extend along the vertical direction, and the transceiving antenna modules19on the two carrying arms12can scan the predetermined scan area by rotating about the same plumb line.

Further, a rotating axis of the first cross arm11may be located at a center of the first cross arm11. This structure may enable the rotary frame10to rotate stably and symmetrically about the rotating axis, and during the operation, the rotary frame10can rotate within a certain range of angles and it can be ensured that the overall deformation or shaking of the rotary frame10in the horizontal direction and the radial direction is below a certain threshold.

Further, the servomotor20may drive the rotary frame10to perform reciprocating scanning motion about the rotating axis. A single time of scanning may cover any angle interval within −90° to 90°. Further, the rotating angle can be 120°, and the same angle can be scanned in the opposite direction during the next time of scanning. The range of angular speed θ for rotary scanning can be 10°/s<θ<80°/s; and the time range for a single time of scanning can be 2 seconds to 10 seconds. This may be selected depending on specific needs.

Alternatively, the number of the carrying arm12can be one, and an inner side of the carrying arm12may be provided with a transceiving antenna module90, the transceiving antenna module90may form a predetermined scan area toward one side of the rotating axis, and the transceiving antenna module90may rotate about a plumb line to scan the predetermined scan area. This solution may achieve partial rotary scanning or cylindrical rotary scanning. For example, the range of the rotating angle of the transceiving antenna module90can be 120°, and when the person stands within the predetermined scanning area, the front and the back sides of the person respectively face the transceiving antenna module90, and the three-dimensional scanning of the human body can be accomplished simply by scanning for two times. Alternatively, the range of the rotating angle of the transceiving antenna module90can be 300°, and when the person stands within the predetermined scanning area, the three-dimensional scanning of the human body can be accomplished simply by scanning for one time.

Further, the rotary frame10may further comprise a second cross arm13connected between the two carrying arms12, and the first cross arm11and the second cross arm13may be disposed opposite to each other. The servomotor20may drive the first cross arm11to rotate, and it may simultaneously drive the transceiving antenna modules90on the two carrying arms12to rotate about the same plumb line to scan the predetermined scan area, and the second cross arm13may enable the rotary frame10to have an overall stable structure and small shaking during the rotation.

Further, the first cross arm11, the two carrying arms12and the second cross arm13may be arranged in a rectangular form. This structure is stable, and during the rotation, the rotary frame10can rotate within a certain range of angles and it can be ensured that the overall deformation or shaking of the rotary frame10in the horizontal direction and the radial direction may be below a certain threshold.

Further, the two carrying arms12may be symmetrically and vertically mounted at two ends of the first cross arm11and the second cross arm13, and the perpendicularity error may be ensured to be within a range of 0.01°. An inner surface of the first cross arm11may be substantially parallel to an inner surface of the second cross arm13, and the actual nonparallelism between the inner surfaces (surfaces toward the center of the cylinder) of the two carrying arms12may be ensured to be within a range of ±0.5 mm/2000 mm. A distance between the inner surfaces of the two carrying arms12can be 1200.00 mm. A line connecting centers of the first cross arm11and the second cross arm13may be the rotating axis of the rotary frame10. During the process of the rotary scanning motion, by adopting the rotary structure in the form of a frame, the relative positional relationship between the transceiving antenna module90and the carrying arm12may be fixed, the relative positional relationship between the transceiving antenna module90and the servomotor20of the rotary structure may be fixed, and the relative positional relationship between the carrying arm12and the servomotor20of the rotary structure may be fixed. The amplitude of the radial and tangential vibration is small. The range of deviation of the relative positional relationship between the transceiving antenna module90and the carrying arm12should be limited so that the amplitude of the radial vibration may be less than ±0.5 mm, and the amplitude of the tangential vibration may be less than ±0.5 mm. The range of deviation of the relative positional relationship between the transceiving antenna module90and the servomotor20of the rotary structure should be limited so that the amplitude of the radial vibration may be less than ±0.5 mm, and the amplitude of the tangential vibration may be less than ±0.5 mm. The range of deviation of the relative positional relationship between the carrying arm12and the servomotor20of the rotary structure should be limited so that the amplitude of the radial vibration may be less than ±0.5 mm, and the amplitude of the tangential vibration may be less than ±0.5 mm. The structure may be detachable and may have a high precision for repeating the assembling, and the precision for repeating the assembling after the parts are detached may be ensured to be within the range of ±0.5 mm/2000 mm.

Further, the first cross arm11, the two carrying arms12and the second cross arm13may be formed into an integral structure or an assembled structure. For example, the first cross arm11, the two carrying arms12and the second cross arm13may be cast integrally, and this solution may be easy for manufacturing and the structure obtained thereby is stable.

Further, the system further comprises a fixing support60having an upper mounting arm61and a lower mounting arm62disposed opposite to each other, and the rotary frame10may be rotatably mounted between the upper mounting arm61and the lower mounting arm62. The fixing support60may facilitate the mounting of the rotary frame10, and the rotary frame10may rotate on the fixing support60stably. The fixing support60may adopt the form of four supporting columns, and the upper mounting arm61and the lower mounting arm62may adopt an I beam, so it may be easy to be manufactured and the structure obtained thereby is stable. As shall be appreciated, it may be also feasible to drive the rotary frame10to rotate by the servomotor20without providing the fixing support60.

Further, the servomotor20may be mounted on the upper mounting arm61, the first cross arm11may be rotatably mounted on the upper mounting arm61, and the second cross arm13may be rotatably mounted on the lower mounting arm62. The overall structure is stable, the shaking during the rotation of the rotary frame10may be small, and the second cross arm13may be arranged at a lower position. The second cross arm13may be provided with a rotating shaft thereon, the lower mounting arm62may have a mounting hole thereon, an end of the rotating shaft may be inserted into the mounting hole, and the rotating shaft may rotate about an axis of the mounting hole to achieve the purpose of rotatably mounting the second cross arm13on the lower mounting arm62.

Further, the servomotor20and the rotating frame10may be connected via a reducer70. The reducer70may improve the output torque by decreasing the output rotation speed so as to drive the rotary frame10to rotate. For this solution, the structure is simple, the mounting is convenient and the positioning precision can be ensured.

Further, the control component40may comprise an upper computer41, a first controller42that may be configured to receive a scan instruction issued by the upper computer41, and a second controller43that may be communicatively connected with the first controller42and electrically connected with the servo driver50. A user may input an instruction via the upper computer41, and the upper computer41may send a control instruction to the second control43via the first controller42and receive returned status information. The first control42may communicate with the second controller43, and the first controller42may send a control command to the second controller43and receive returned status information. The second controller43may send enable control and scan direction instructions and a scan speed instruction to the servo driver50according to the received control command, and may control the servomotor20to rotate indirectly via the servo driver50. The rotation speed of the servomotor20may be preset in the servo driver50, and the servo driver50may drive the servomotor20to run at different speed modes according to different speed instructions. The servo driver50may preset various running modes to satisfy requirements of precise rotation and positioning. Meanwhile, the servomotor20may have the first angle sensor21built therein, the first angle sensor21may generate and feed back a pulse sequence to the second controller43to analyze the running status of the servomotor20during the operation of the servomotor20, and may return the status information to a program of the upper computer41. The second angle sensor30may generate a pulse signal and feed the pulse signal back to the second controller43in real time, and the servo driver50may drive the servomotor20to rotate. The second angle sensor30may input the pulse signal to the first controller42, and the first controller42may process the received pulse signal to determine whether to trigger the operation of the transceiving antenna module90and other modules.

Specifically, the first controller42may be a PLC programmable logic device. The second controller43may be an FPGA control panel. The PLC programmable logic device may cooperate with the FPGA control panel so that the overall system is more stable, the later maintenance may be convenient and the probability of failure of the overall system can be reduced. The FPGA control panel communicates with the PLC programmable logic device, the communication interface may adopt RS422/RS232 or network ports to achieve communication, and a communication protocol with the PLC programmable logic device may comprise a frame header, an instruction word, a status word, a frame count and parity bit information. The communication protocol between the PLC programmable logic device and the servo driver50may satisfy design requirements of the driver. The FPGA control panel may generate various kinds of triggering signals and time sequence signals to trigger the operation of the transceiving antenna module90and other apparatuses. The number of triggering interfaces of the FPGA control panel may be greater than 2, and the apparatuses triggered by the FPGA control panel may include but not limited to the transceiving antenna module90. Moreover, the signals may be output via multiple channels, and the time sequence signals may be output through the combination of multiple channels to trigger or control other apparatuses, e.g., output by the combination of four channels to generate independent time signals of 16 bits. It shall be appreciated that, other types of controllers may also be selected as the first controller42and the second controller43.

Further, the second angle sensor30may be an encoder, and the encoder may detect an actual rotating angle signal of the rotary frame10in real time and input the signal to the first controller42. During the process of scanning motion, the servo rotary scanning system may calculate the number of square signals to determine the rotated angle, and the resolution of the angle position may be superior to 0.005°. One position triggering signal may be sent every Δθ (Δθ is an angle interval, Δθ is an angle determined between 0.20° and 0.40°), and during the rotary scanning motion having an effective travel of θ, a total of N (N=θ/Δθ, taking the integer part of N) angle position triggering signals may be outputted. The angle interval of the scanning motion may be set by the communication interface with a program in the second controller43. During the process of reciprocating scanning, the repeated positioning precision of the upper mounting arm61and the lower mounting arm62may be ±0.01° (repeated for 100 times); the absolute positioning precision of the upper mounting arm61and the lower mounting arm62may be ±0.01°; and the angle position error corresponding to the position triggering pulse should be superior to ±0.01°.

Further, the system further may comprise a rotation direction sensor80that is configured to detect positive and negative rotating orientations of the rotary frame10and limit the rotating angle of the rotary frame10, and the rotation direction sensor80may be electrically connected with the second controller43. The rotation direction sensor80may monitor the current positive and negative orientation of the rotary frame10in real time and obtain an absolute zero position, and the rotation direction sensor80may further monitor whether the frame selected for use exceeds a limiting position and feeds status information back to the second controller43. Specifically, the rotation direction sensor80may be an optoelectronic switch, a combination of two rotary encoders or other rotation direction sensors. The rotation direction sensor80mounted on the rotating axis and fixed on the fixing support60may adopt the optoelectronic switch, and takes 0° as a center zero position, wherein the negative angle is the negative direction, and the positive angle is the positive direction. The optoelectronic switch may distinguish the position and negative directions by outputting a high or low level, and the jumping point between the high level and the low level may be the center zero position. Alternatively, the rotation direction sensor80may adopt two rotary encoders, and the two rotary encoders may output two sets of pulses of which the phase difference is 90 degrees, and the rotation speed can be measured and the direction of the rotation can be determined according to the two sets of pulses. Furthermore, it may be set inside the rotation direction sensor80that the positive level and the negative level are only output within a certain range of angles, e.g., which may be limited to ±60°, and when the limited angle is exceeded, different signals may be output to indicate that the scanning angle exceeds the specified upper limit of the range and the signals may be sent to the second controller43so that security measures can be adopted. The measures that can be selected include but not limited to turning off the power, enabling the motor to suspend, and idling of the motor without load or the like. The rotation direction sensor80may transmit the orientation signal, the limiting signal or the like to the second controller43in real time so as to control the servomotor20to rotate in a correct and safe manner.

Further, the system further may comprise a power source for providing electrical energy for devices such as the servo motor20, the control component40and the servo driver50or the like.

Referring toFIG. 2andFIG. 3, a servo rotary scanning system of three-dimensional holographic imaging provided according to a second embodiment of the present disclosure is generally the same as the servo rotary scanning system of three-dimensional holographic imaging provided according to the first embodiment, and the second embodiment differs from the first embodiment in that, the servomotor20may be disposed on the lower mounting arm62, the first cross arm11may be rotatably mounted on the lower mounting arm62, and the second cross arm13may be rotatably mounted on the upper mounting arm61. The overall structure is stable, the shaking of the rotary frame10may be small during the rotation, the servomotor20may be convenient to be mounted, and the overall system is safe in use. The second cross arm13may be provided with a rotating shaft thereon, the upper mounting arm61may have a mounting hole thereon, an end of the rotating shaft may be inserted into the mounting hole, and the rotating shaft may rotate about an axis of the mounting hole to achieve the purpose of rotatably mounting the second cross arm13on the upper mounting arm61.

The servo rotary scanning system of three-dimensional holographic imaging may include the servomotor20having the first angle sensor21, the second angle sensor30, the control component40, the servo driver50and the rotary frame10, the servo rotary scanning system of three-dimensional holographic imaging may be a full-closed loop servo control system, the second angle sensor30may detect the actual rotating angle of the rotary frame10and feed back a frame feedback signal A to the control component40, an instruction signal I in the control component40may be compared with the frame feedback signal A to generate a following error E, the first angle sensor21may detect an output rotating angle of the servomotor20and feed back a motor feedback signal B to the servo driver50, and the servo driver50may control the servomotor20to rotate according to the following error E and the motor feedback signal B. The servo rotary scanning system of three-dimensional holographic imaging may have a simple structure, a lower cost and a high rotation precision and may be easy to be assembled and controlled. The rotary frame10can ensure stable start and stop of the scanning even at a higher running speed. To cooperate with the accurate transmitting and receiving of the signal of the transceiving antenna module90, the rotation of the servomotor20and the transceiving of the transceiving antenna module90can be ensured to be performed simultaneously at time sequence, and the requirements for the real-time monitoring and the inspection of the servo control system can be satisfied. During the multiple reciprocating scanning processes of the servo control system, the start and end positions of each scanning can be positioned accurately, the real-time output rotating angle of the servomotor20and the actual rotating angle of the rotary frame10can be fed back in time and the time delay of the feedback satisfies certain requirements.

What described above are only the embodiments of the present disclosure, but are not intended to limit the scope of the present disclosure. Any equivalent structures or equivalent process flow modifications that are made according to the specification and the attached drawings of the present disclosure, or any direct or indirect applications of the present disclosure in other related technical fields shall all be covered within the scope of the present disclosure.