Active and passive integrated vibration isolation, suppression and stabilization parallel robot system

Abstract

The utility model relates to the technical field of vibration isolation and parallel robots, and discloses an active and passive integrated vibration isolation, suppression and stabilization parallel robot system, which comprises a movable platform for mounting photoelectric equipment; the static platform is mounted on the vehicle body as a base; the inertial measurement unit is used for measuring low-frequency disturbance of the vehicle body or the static platform; the motion branch chain group can actively change the length to keep the stability of the movable platform; and the constraint branch chain is used for limiting other motions except pitching and rolling in the vertical direction of the movable platform and in reference to the static platform. Compared with other vibration isolation platforms on the market, the advantages of active vibration suppression and passive vibration isolation are combined, and the good vibration isolation and suppression effect can be achieved within the wide frequency range; a parallel robot structure is adopted, the structure is compact, the rigidity is high, the accumulated error is small, the movement precision and the response speed are high, and the imaging quality and the tracking and pointing precision of precise photoelectric equipment can be improved.

Description

An integrated active and passive vibration isolation and stabilization parallel robot system Technical Field

[0001] This utility model relates to the field of vibration isolation and parallel robot technology, specifically, it is an active-passive integrated vibration isolation and stabilization parallel robot system. Background Technology

[0002] In the automotive field, vibration isolation platforms are often used to mount precision optoelectronic equipment for imaging, tracking, or aiming functions. As they move with the vehicle, they face various complex vibration and shock excitations and motion disturbances, thus requiring high vibration isolation and stabilization performance from the vibration damping system between them and the vehicle body. Insufficient vibration isolation and stabilization performance can lead to blurred imaging, poor tracking accuracy, or even equipment damage, and may even cause equipment collisions and interference.

[0003] Existing vibration isolation platforms are mainly passive vibration isolation platforms. They utilize the elasticity and damping characteristics of vibration isolation elements (such as springs and rubber) to reduce the vibration amplitude transmitted to the equipment. They can effectively isolate mid-to-high frequency vibrations (20-500Hz) caused by factors such as vehicle structure, vehicle engine, idling vibration, and constant speed driving. However, they are not very effective for low-frequency and ultra-low-frequency vibrations (0-20Hz) and multi-dimensional vibrations. Furthermore, they have poor stability performance and do not have active vibration suppression capabilities.

[0004] The integrated active-passive vibration isolation and suppression system comprises a damper and an actuator. The damper, as a passive vibration isolation device, effectively isolates mid-to-high frequency vibrations; the actuator, as an active vibration suppression device, enables rapid attitude adjustment and stabilization, exhibiting high vibration suppression effectiveness for low-frequency and ultra-low-frequency vibrations. Overall, the integrated active-passive vibration isolation and suppression system can achieve broadband vibration isolation and suppression. It combines the advantages of active vibration suppression for low frequencies with the effectiveness of passive vibration isolation for mid-to-high frequency vibrations, representing the current major development trend. Summary of the Invention

[0005] This invention addresses the high-performance vibration isolation and stability requirements of vibration isolation platforms in the automotive field. Under strict constraints such as size, space, and weight, it proposes an active-passive integrated vibration isolation and stabilization parallel robot system. This system solves the problem that existing equipment cannot meet the performance requirements of wideband vibration isolation and rapid stabilization between precision optoelectronic equipment and the vehicle body when facing low-frequency and ultra-low-frequency large-amplitude vibrations and multi-dimensional vibration scenarios.

[0006] This utility model is achieved through the following technical solution: a parallel robot system with integrated active and passive vibration isolation and stabilization, comprising: a moving platform for mounting photoelectric equipment; a stationary platform, which serves as a base mounted on a vehicle body; an inertial measurement unit for measuring low-frequency disturbances of the vehicle body or the stationary platform; a motion branch assembly, mounted on the stationary platform with its other end connected to the moving platform, the motion branch assembly being able to actively change its length to maintain the stability of the moving platform, the motion branch assembly including a motion branch and a damper, wherein the damper is connected to the stationary platform, the motion branch is connected to the moving platform, and the motion branch is connected to the damper; and a constraint branch assembly, mounted on the stationary platform with its other end connected to the moving platform, for restricting movements other than the vertical direction of the moving platform and pitch and roll relative to the stationary platform, the constraint branch assembly including a constraint branch.

[0007] To better realize this utility model, the motion chain further includes a first inclined platform, a ball joint, a push rod, a drive unit, and a first universal joint. The push rod is connected to the drive unit in a transmission manner. The first inclined platform is mounted on the moving platform. The first inclined platform is connected to the push rod through the ball joint. The drive unit is connected to the damper through the first universal joint. The static platform includes a base and a second inclined platform. The second inclined platform is mounted on the base. The damper is connected to the second inclined platform.

[0008] To better realize this utility model, the drive unit further includes a structural component, a servo motor, a transmission component, and a ball screw module. The servo motor, transmission component, and ball screw module are all mounted on the structural component. The transmission component is used to transmit the power of the servo motor to the ball screw module. The start and stop of the servo motor are controlled by the inertial measurement unit. A dust cover is installed on the structural component to protect the transmission component.

[0009] To better realize this utility model, the transmission component further includes a second boss gear, a first boss gear, a transmission gear, and an elastic retaining ring. The second boss gear is installed at the output end of the servo motor. The first boss gear is rotatably connected to the structural component and is transmitted to the ball screw module. The transmission gear is rotatably connected to the structural component. An elastic retaining ring is installed on the structural component to limit the transmission gear. The transmission gear meshes with the first boss gear and the second boss gear respectively.

[0010] To better realize this utility model, the ball screw module further includes a ball screw, a nut, and a fixing seat. The fixing seat is installed on the structural component, the ball screw is rotatably connected to the fixing seat, the nut is threadedly connected to the ball screw, and the nut is connected to the push rod.

[0011] To better realize this utility model, the constraint branch further includes a second universal joint, a movable rod, a linear bearing, and a limiting rod. The movable rod is slidably connected to the limiting rod through the linear bearing, and the movable rod is connected to the moving platform through the second universal joint. The limiting rod is installed on the stationary platform.

[0012] To better realize this utility model, the constraint branch further includes a limiting pin, and the limiting rod has a strip-shaped hole. The limiting pin is installed at the end of the movable rod and slides in cooperation with the strip-shaped hole.

[0013] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0014] (1) This utility model combines the advantages of active vibration suppression and passive vibration isolation, and can achieve good vibration isolation and stabilization effect in a wide frequency range; the spring damper used can naturally absorb and dissipate the energy of mid-to-high frequency vibration, so the passive vibration isolation part can effectively attenuate mid-to-high frequency vibration; at the same time, the active vibration suppression part uses sensors and controllers such as inertial sensors to accurately compensate for low-frequency vibration, and cancels low-frequency vibration by generating a force opposite to the direction of the interference vibration, so as to achieve full-band vibration isolation and suppression.

[0015] (2) This utility model adopts a parallel structure, which is compact and has high rigidity, and has high motion accuracy and response speed. The moving platform is driven by multiple branches at the same time, making the motion of the moving platform more accurate and stable, and also making the motion of the precision optoelectronic and imaging equipment mounted on it more accurate and stable, meeting its rapid posture stabilization requirements. Compared with serial robots, its cumulative error is smaller, and it has inherent advantages in spatial positioning and posture adjustment.

[0016] (3) The present invention arranges the drive unit on the motion chain and uses the ball screw as part of the chain, which achieves smaller size, lower weight and higher transmission efficiency, and can meet some usage requirements in some narrow spaces and under medium and low load conditions.

[0017] (4) In actual working scenarios, the frequency and intensity of vibration may change at any time. This utility model can automatically adjust the vibration isolation and suppression strategy according to the real-time changes of vibration.

[0018] (5) This utility model can not only meet the high performance isolation, vibration suppression and stabilization requirements of precision optoelectronic equipment in the vehicle field, but also be used with other equipment in other situations where there are size, space and weight restrictions; in addition, encoders, Beidou satellite system and force sensors can be added to the equipment, and the equipment can also be connected to terminals such as cloud brain for real-time monitoring of the mounted equipment. Attached Figure Description

[0019] Figure 1 is a schematic diagram of the installation and use of this utility model.

[0020] Figure 2 is a schematic diagram of the overall structure of this utility model.

[0021] Figure 3 is a schematic diagram of the kinematic branch group structure.

[0022] Figure 4 is a schematic diagram of the decomposition of the kinematic branch structure.

[0023] Figure 5 is a schematic diagram of the damper structure.

[0024] Figure 6 is a schematic diagram of the static platform structure.

[0025] Figure 7 is a schematic diagram of the constrained branch structure.

[0026] Wherein: 100-Vehicle body; 200-Robot system; 300-Optoelectronic equipment; 210-Moving platform; 220-Kinematic chain; 221-First inclined plane; 222-Spherical hinge; 223-Push rod; 224-Drive unit; 2240-Elastic retaining ring; 2241-Ball screw; 2242-Nut; 2243-Fixed seat; 2244-First boss gear; 2245-Transmission gear; 2246 - Structural component; 2247 Servo motor; 2248 Second boss gear; 2249 Dust cover; 225 First universal joint; 230 Damper; 240 Static platform; 241 Base; 242 Second inclined platform; 250 Inertial measurement unit; 260 Constraint chain; 261 Second universal joint; 262 Movable rod; 263 Linear bearing; 264 Limit pin; 265 Limit rod. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] Example 1:

[0030] To effectively isolate and suppress various complex vibration shocks and motion disturbances encountered by vehicles during movement, especially low-frequency and ultra-low-frequency large-amplitude vibrations (0-20Hz) and multi-dimensional vibrations, and to meet the performance requirements of broadband vibration isolation, suppression, and rapid stabilization between precision optoelectronic equipment and the vehicle body, this invention addresses the vibration isolation platform in the vehicle field. Under strict constraints of size, space, and weight, it combines the advantages of active and passive vibration suppression to invent an integrated active-passive vibration isolation and stabilization parallel robot system, as shown in Figures 1-2. The system includes a robot system 200, comprising: a moving platform 210 for mounting optoelectronic equipment 300; a stationary platform 240, serving as a base mounted on the vehicle body 100; an inertial measurement unit 250 for measuring low-frequency disturbances in the vehicle body 100 or the stationary platform 240; and a motion chain assembly mounted on the stationary platform 240, with one end connected to the moving platform 210. The motion chain assembly is connected to the stationary platform 240. The motion chain assembly can actively change its length to maintain the stability of the moving platform 210. The motion chain assembly includes a motion chain 220 and a damper 230, wherein the damper 230 is connected to the stationary platform 240, the motion chain 220 is connected to the moving platform 210, and the motion chain 220 is connected to the damper 230. A constraint chain assembly is installed on the stationary platform 240, with one end connected to the moving platform 210. It is used to restrict movements other than the vertical direction of the moving platform 210 and pitch and roll movements relative to the stationary platform 240. The constraint chain assembly includes a constraint chain 260.

[0031] Overall dimensions less than 300×300×300mm; self-weight less than 10kg; load capacity: 10kg; active vibration damping and attitude adjustment range: pitch and roll ±30°, vertical displacement 40mm.

[0032] The active vibration suppression principle is as follows: When the inertial measurement unit 250 detects a low-frequency large-amplitude disturbance in the vehicle body 100 or the static platform 240, within the active attitude adjustment range, it can control the motion chain 220 to change its length and transmit the motion to the moving platform 210, causing the moving platform 210 to tilt to a certain angle, thereby offsetting the disturbance brought to the photoelectric device 300 by the vehicle body 100, and thus achieving the purpose of suppressing low-frequency vibration.

[0033] The passive vibration isolation principle is as follows: The damper 230 mainly consists of a cylinder, a piston, a piston rod, and damping fluid. When high-frequency vibrations are transmitted from the vehicle body 100 to the damper 230 via the static platform 240, the piston inside the damper 230 moves back and forth within the cylinder. The damping fluid flows back and forth through small holes or gaps on the piston, generating friction with the cylinder and piston rod, thus converting the vibration energy into heat energy and dissipating it.

[0034] The vibration transfer function of the active-passive integrated vibration isolation and stabilization parallel robot system is:

[0035] After converting the signal to its amplitude-frequency characteristics using Fourier transform, the transmissibility formula for this vibration-damping and stability-enhancing parallel robot system can be obtained:

[0036] In the formula: k is the total stiffness of the vibration-damping and stabilizing parallel robot, c is the damping coefficient of the vibration-damping and stabilizing parallel robot, and m is 15kg (the sum of the load-bearing mass of the vibration-damping and stabilizing parallel robot system and the mass of some of its own parts). Let f be the transmissivity at frequency f.

[0037] Calculations show that when the damping of a single damper 230 used in this embodiment is 53.24 N·s / m, the active-passive integrated vibration isolation and stabilization parallel robot system can meet the passive vibration isolation performance indicators. Specifically, it meets the following requirements: vibration transmissibility ≤ 10dB in the 2-25Hz frequency range (i.e., resonance amplification factor ≤ 3.16); vibration transmissibility ≤ -20dB in the 25-500Hz frequency range (i.e., vibration isolation rate ≥ 90%, vibration transmissibility ≤ 0.1).

[0038] Example 2:

[0039] This embodiment further expands the motion chain 220 based on the above embodiment, as shown in Figures 3-6. The motion chain 220 includes a first ramp 221, a ball joint 222, a push rod 223, a drive unit 224, and a first universal joint 225. The push rod 223 is connected to the drive unit 224. The first ramp 221 is mounted on the moving platform 210 and is connected to the push rod 223 through the ball joint 222. The drive unit 224 is connected to the damper 230 through the first universal joint 225. The stationary platform 240 includes a base 241 and a second ramp 242. The second ramp 242 is mounted on the base 241, and the damper 230 is connected to the second ramp 242.

[0040] Furthermore, the drive unit 224 includes a structural component 2246, a servo motor 2247, a transmission component, and a ball screw module. The servo motor 2247, the transmission component, and the ball screw module are all mounted on the structural component 2246. The transmission component is used to transmit the power of the servo motor 2247 to the ball screw module. The start and stop of the servo motor 2247 are controlled by the inertial measurement unit 250. A dust cover 2249 is installed on the structural component 2246 to protect the transmission component.

[0041] Furthermore, the transmission component includes a second boss gear 2248, a first boss gear 2244, a transmission gear 2245, and an elastic retaining ring 2240. The second boss gear 2248 is mounted on the output end of the servo motor 2247. The first boss gear 2244 is rotatably connected to the structural component 2246 and is connected to the ball screw module for transmission. The transmission gear 2245 is rotatably connected to the structural component 2246. An elastic retaining ring 2240 is installed on the structural component 2246 to limit the transmission gear 2245. The transmission gear 2245 meshes with the first boss gear 2244 and the second boss gear 2248 respectively.

[0042] Furthermore, the ball screw module includes a ball screw 2241, a nut 2242, and a fixing seat 2243. The fixing seat 2243 is mounted on the structural component 2246. The ball screw 2241 is rotatably connected to the fixing seat 2243. The nut 2242 is threadedly connected to the ball screw 2241 and is connected to the push rod 223.

[0043] Furthermore, the constraint branch 260 includes a second universal joint 261, a movable rod 262, a linear bearing 263, and a limiting rod 265. The movable rod 262 is slidably connected to the limiting rod 265 through the linear bearing 263. The movable rod 262 is connected to the moving platform 210 through the second universal joint 261. The limiting rod 265 is mounted on the stationary platform 240.

[0044] Furthermore, the constraint branch 260 also includes a limiting pin 264, and the limiting rod 265 has a strip-shaped hole. The limiting pin 264 is installed at the end of the movable rod 262 and slides in cooperation with the strip-shaped hole.

[0045] During active vibration damping, the pitch and roll movements are controlled by the inertial measurement unit 250, which independently starts three servo motors 2247. This causes the second boss gear 2248 to rotate, which drives the transmission gear 2245, which in turn drives the first boss gear 2244. The first boss gear 2244 then drives the ball screw 2241 to rotate. At this time, the ball screw 2241 drives the fixed seat 2243 and the push rod 223 to move synchronously and linearly. This movement is then transmitted to the moving platform 210 through the ball joint 222 and the first inclined platform 221, thereby realizing the overall length change of the motion chain 220. By adjusting the three sets of motion chain groups together and combining the inverse kinematics of the parallel mechanism, the distance that each nut 2242 moves along the ball screw 2241 in any pose can be calculated. Then, by rotating the servo motors 2247, the moving platform 210 can reach the required angle. Vertical movement requires three servo motors 2247 to rotate forward or reverse at the same speed, so that the three nuts 2242 move along the three ball screws 2241 at the same speed and direction. The cooperation between the limit pin 264 and the limit rod 265 in the movable rod 262 enables the constraint chain 260 to move vertically. Combined with inverse kinematics, the moving platform 210 can be controlled to achieve vertical movement.

[0046] The other parts of this embodiment are the same as those in the above embodiments, and will not be described again.

[0047] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A parallel robot system integrating active and passive vibration isolation and stabilization, characterized in that... The system includes: a moving platform (210) for mounting optoelectronic equipment (300); a stationary platform (240) mounted on the vehicle body (100) as a base; an inertial measurement unit (250) for measuring low-frequency disturbances of the vehicle body (100) or the stationary platform (240); and a motion chain assembly mounted on the stationary platform (240), with one end connected to the moving platform (210). The motion chain assembly can actively change its length to maintain the stability of the moving platform (210). The motion chain assembly includes a motion chain (220) and a damper (…). 230), wherein the damper (230) is connected to the stationary platform (240), the motion chain (220) is connected to the moving platform (210), and the motion chain (220) is connected to the damper (230); a constraint chain group, installed on the stationary platform (240) and connected at one end to the moving platform (210), is used to restrict other movements other than the vertical direction of the moving platform (210) and the pitch and roll movements relative to the stationary platform (240), and the constraint chain group includes a constraint chain (260).

2. The active-passive integrated vibration isolation and stabilization parallel robot system according to claim 1, characterized in that: The motion chain (220) includes a first ramp (221), a ball joint (222), a push rod (223), a drive unit (224), and a first universal joint (225). The push rod (223) is connected to the drive unit (224) in a transmission manner. The first ramp (221) is mounted on the moving platform (210). The first ramp (221) is connected to the push rod (223) through the ball joint (222). The drive unit (224) is connected to the damper (230) through the first universal joint (225). The stationary platform (240) includes a base (241) and a second ramp (242). The second ramp (242) is mounted on the base (241). The damper (230) is connected to the second ramp (242).

3. The active-passive integrated vibration isolation and stabilization parallel robot system according to claim 2, characterized in that: The drive unit (224) includes a structural component (2246), a servo motor (2247), a transmission component, and a ball screw module. The servo motor (2247), the transmission component, and the ball screw module are all mounted on the structural component (2246). The transmission component is used to transmit the power of the servo motor (2247) to the ball screw module. The start and stop of the servo motor (2247) are controlled by the inertial measurement unit (250). A dust cover (2249) is installed on the structural component (2246) to protect the transmission component.

4. The active-passive integrated vibration isolation and stabilization parallel robot system according to claim 3, characterized in that: The transmission component includes a second boss gear (2248), a first boss gear (2244), a transmission gear (2245), and an elastic retaining ring (2240). The second boss gear (2248) is installed at the output end of the servo motor (2247). The first boss gear (2244) is rotatably connected to the structural component (2246) and is connected to the ball screw module. The transmission gear (2245) is rotatably connected to the structural component (2246). An elastic retaining ring (2240) is installed on the structural component (2246) to limit the transmission gear (2245). The transmission gear (2245) meshes with the first boss gear (2244) and the second boss gear (2248) respectively.

5. The active-passive integrated vibration isolation and stabilization parallel robot system according to claim 3, characterized in that: The ball screw module includes a ball screw (2241), a nut (2242), and a fixing seat (2243). The fixing seat (2243) is mounted on the structural component (2246). The ball screw (2241) is rotatably connected to the fixing seat (2243). The nut (2242) is threadedly connected to the ball screw (2241). The nut (2242) is connected to the push rod (223).

6. A parallel robot system with integrated active and passive vibration isolation and stabilization according to any one of claims 1-5, characterized in that: The constraint branch (260) includes a second universal joint (261), a movable rod (262), a linear bearing (263), and a limiting rod (265). The movable rod (262) is slidably connected to the limiting rod (265) through the linear bearing (263). The movable rod (262) is connected to the moving platform (210) through the second universal joint (261). The limiting rod (265) is installed on the stationary platform (240).

7. The active-passive integrated vibration isolation and stabilization parallel robot system according to claim 6, characterized in that: The constraint branch (260) also includes a limiting pin (264). The limiting rod (265) has a strip hole. The limiting pin (264) is installed at the end of the movable rod (262) and slides in cooperation with the strip hole.

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