CN113928605A - Micro-low gravity environment simulation device and method for variable mass load - Google Patents
Micro-low gravity environment simulation device and method for variable mass load Download PDFInfo
- Publication number
- CN113928605A CN113928605A CN202111350488.7A CN202111350488A CN113928605A CN 113928605 A CN113928605 A CN 113928605A CN 202111350488 A CN202111350488 A CN 202111350488A CN 113928605 A CN113928605 A CN 113928605A
- Authority
- CN
- China
- Prior art keywords
- load equipment
- load
- mass
- top plate
- linear actuator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005484 gravity Effects 0.000 title claims abstract description 93
- 238000004088 simulation Methods 0.000 title claims abstract description 51
- 238000000034 method Methods 0.000 title claims abstract description 33
- 230000033001 locomotion Effects 0.000 claims abstract description 76
- 238000012544 monitoring process Methods 0.000 claims abstract description 31
- 230000007246 mechanism Effects 0.000 claims description 90
- 230000008859 change Effects 0.000 claims description 48
- 238000006073 displacement reaction Methods 0.000 claims description 43
- 230000001133 acceleration Effects 0.000 claims description 22
- 238000002347 injection Methods 0.000 claims description 7
- 239000007924 injection Substances 0.000 claims description 7
- 230000005486 microgravity Effects 0.000 claims description 7
- 238000009434 installation Methods 0.000 claims description 6
- 230000005540 biological transmission Effects 0.000 claims description 4
- 230000006835 compression Effects 0.000 claims description 4
- 238000007906 compression Methods 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 230000000694 effects Effects 0.000 claims description 3
- 230000005284 excitation Effects 0.000 claims description 3
- 238000004458 analytical method Methods 0.000 claims description 2
- 230000001360 synchronised effect Effects 0.000 claims description 2
- 238000012360 testing method Methods 0.000 abstract description 8
- 230000004044 response Effects 0.000 abstract description 4
- 230000008569 process Effects 0.000 description 6
- 230000003068 static effect Effects 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 238000006124 Pilkington process Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64G—COSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR
- B64G7/00—Simulating cosmonautic conditions, e.g. for conditioning crews
Abstract
The invention discloses a micro low gravity environment simulation device and a method for variable mass load, belonging to the field of micro low gravity simulation test, wherein the device comprises a near zero stiffness supporting component, a motion following component and a load equipment quality monitoring component, wherein the near zero stiffness supporting component and the motion following component are connected up and down to form a series structure, the load equipment quality monitoring component is connected with the variable mass load, the variable mass load is fixed or hinged on the near zero stiffness supporting component, the load equipment quality monitoring component comprises a load equipment controller and a load quality sensing unit, the load equipment controller is connected with the load quality sensing unit, and the load equipment sensing unit is used for monitoring the mass consumption of the load equipment in real time and transmitting signals of the mass consumption to the load equipment controller, thereby controlling and performing corresponding compensation. The device and the method have the advantages of high response precision, high speed and larger device stroke, and are used for realizing high-fidelity and variable-mass vertical gravity environment simulation in a large stroke.
Description
Technical Field
The invention belongs to the field of aerospace engineering micro-low gravity simulation tests, and particularly relates to a micro-low gravity environment simulation device and method for variable mass loads.
Background
The design, development and development cost of the spacecraft and the risk of executing tasks in orbit are high, and in order to ensure the operation reliability and safety of the spacecraft, the performance verification of the spacecraft must be carried out on the ground before launching and lifting, so that a high-fidelity low-gravity environment needs to be simulated.
The general simulation method of the low gravity environment found by consulting the literature is divided into the following steps according to the principle: the method comprises the steps of simulating microgravity by a motion method and simulating microgravity by a force balance method, wherein the motion method comprises a tower falling method, a parabolic flight method, a sounding rocket method and the like, and the force balance method comprises an air float method, a water float method, a suspension method, a static balance mechanism method, an electromagnetic balance method and the like.
The device of the static balance method has the advantages of exquisite structure, easy realization, realization of multi-degree-of-freedom microgravity simulation, small additional inertia effect and easy influence of factors such as spring stiffness on the precision of the microgravity simulation.
In addition, the existing static balance method micro-low gravity environment simulation device mainly adopts a constant force air cylinder to unload gravity, so that micro-low gravity environment simulation is achieved, but due to the problems of nonlinear control and time lag caused by strong compressibility of gas, the precision and response speed of micro-low gravity environment simulation are seriously influenced, and the requirement of micro-low gravity environment simulation of a spacecraft cannot be met. Secondly, in the simulation process of the micro-low gravity environment, the load equipment may cause real-time load quality change due to active operations such as air injection orbital transfer or attitude adjustment, and the change of the support height caused by the real-time quality change needs to be compensated to ensure the precision of the simulation test.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a simulation device and a simulation method for a micro-low gravity environment with variable mass load, and aims to solve the problem of low gravity unloading precision of the simulation device for the micro-low gravity environment.
To solve the above problems, according to one aspect of the present invention, there is provided a low gravity environment simulation apparatus for variable mass loads, comprising a near-zero stiffness support module, a motion follower module and a load device mass monitoring module, wherein the near-zero stiffness support module and the motion follower module are independent of each other, and the near-zero stiffness support module and the motion follower module are connected up and down to form a series structure, the load device mass monitoring module is connected with the variable mass load, the variable mass load is fixed or hinged on the near-zero stiffness support module,
the near-zero stiffness supporting assembly comprises a top plate, a bottom plate, a passive supporting unit and a linear actuator, wherein the passive supporting unit and the linear actuator are arranged between the top plate and the bottom plate, the top plate is parallel to the bottom plate, the top plate is used for bearing load equipment to be simulated, the bearing capacity of the passive supporting unit is greater than the gravity borne by the load equipment to be simulated, the motion following assembly is connected with the bottom plate and used for providing excitation for the bottom plate so as to enable the bottom plate to follow the top plate to generate preset speed and motion,
the load equipment quality monitoring assembly comprises a load equipment controller and a load quality sensing unit, wherein the load equipment controller is connected with the load quality sensing unit, the load equipment sensing unit is used for monitoring the mass consumption of the load equipment in real time and transmitting a signal of the mass consumption to the load equipment controller, the load equipment controller is also connected with a linear actuator in a signal mode,
during work, when the mass of the load equipment changes, the mass consumption of the load equipment is monitored in real time through the load mass sensing unit, signals of the mass consumption are transmitted to the load equipment controller, the load equipment controller generates a mass change compensation feed-forward force signal, the linear actuator compensates the load equipment in real time through the top plate according to the feed-forward force signal, the passive support unit, the linear actuator and the motion following assembly cooperate together to provide a celestial sphere surface or space stress environment with the gravity acceleration g 'for the load equipment to be simulated, wherein the gravity acceleration g is greater than or equal to 0 and smaller than g' < g, and g is the gravity acceleration of the earth surface.
Further, the load mass sensing unit comprises a gas pressure sensor and a mass flow meter, the gas pressure sensor is arranged in the load equipment gas storage tank and is provided with at least one gas pressure sensor used for monitoring the pressure change in the load equipment gas storage tank so as to calculate the gas mass consumption, and the mass flow meter is arranged in the load equipment gas injection pipeline and is provided with at least one gas flow meter used for directly monitoring the gas mass consumption sprayed out of each gas nozzle of the load equipment.
Further, a plurality of gas pressure sensors are arranged at different positions in the whole load equipment, and a plurality of mass flow meters are arranged at different positions in the gas injection pipeline of the whole load equipment.
Further, a gas pressure sensor monitors the pressure change in a gas storage tank of the load equipment or in a pneumatic system in real time, the gas quality consumption is calculated, a mass flow meter monitors the gas quality consumption sprayed out of each gas nozzle in real time, monitoring signals are transmitted to a load equipment controller, the load equipment controller fuses the gas quality consumption fed back by the gas pressure sensor and the mass flow meter, automatic analysis is executed according to set criteria, accurate load equipment quality change quantity is obtained, the load equipment controller generates a feed-forward force signal for compensating the quality change according to the obtained quality consumption, and an instruction is output to control the output of the linear actuator.
The near-zero stiffness supporting assembly further comprises a guide mechanism, the motion following assembly comprises a displacement sensor, a linear motion mechanism, a drive control module and a base, wherein the passive supporting unit comprises a positive stiffness element and a negative stiffness element which are connected in parallel, the positive stiffness element and the negative stiffness element are arranged between the top plate and the bottom plate, the passive supporting unit is used for passively supporting the gravity of load equipment, the guide mechanism is also arranged between the top plate and the bottom plate and is simultaneously connected with the top plate and the bottom plate, and the guide mechanism is used for frictionless guiding in the motion direction and limiting the relative torsion between the top plate and the bottom plate so as to avoid the mutual interference of parts; the displacement sensor is arranged between the top plate and the bottom plate, the upper end of the displacement sensor is connected with the top plate, and the lower end of the displacement sensor is connected with the bottom plate and used for monitoring the height change of the passive support unit; the linear motion mechanism is connected below the bottom plate, so that the passive support unit can perform preset movement in the gravity direction of the load equipment; the driving control module is respectively electrically connected with the displacement sensor, the linear motion mechanism, the linear actuator and the load equipment controller, and is used for driving and controlling the linear motion mechanism according to the received signal information of the displacement sensor and controlling the linear actuator to move according to the signal of the load equipment controller; the top surface of the base is connected with the fixed end of the linear motion mechanism, and the bottom surface of the base is fixedly connected to an external foundation;
when the device works, the drive control module receives feedback signals of the displacement sensor and the load equipment controller, controls the linear actuator and the linear motion mechanism to move, ensures that the relative displacement between the top plate and the bottom plate is constant, enables the rigidity of the passive supporting unit to be close to zero and the deformation to be close to zero, generates mass change compensation for the mass consumption of variable mass load equipment, and enables the supporting force fluctuation of the top plate to the load equipment to be close to zero.
Further, the linear actuator comprises a stator and a rotor, the stator is connected with the bottom plate, the rotor is connected with the top plate, the linear actuator and the passive support unit are connected in parallel, the relative height of the linear actuator and the relative height of the passive support unit can be adjusted, and the difference of the middle point of the effective working stroke of the linear actuator and the passive support unit in height is not more than 1mm or not more than 1/10 of the minimum working stroke of the linear actuator and the passive support unit.
Further, the positive stiffness element is connected with a height adjusting mechanism in a matching mode, the height adjusting mechanism is used for adjusting the relative installation height of the passive support unit and the linear actuator, the height adjusting mechanism comprises a nut and a stud, the nut penetrates through the stud and is connected with the positive stiffness element in a matching mode, the stud is fixedly connected with the bottom plate, and the nut can be rotated to adjust the relative installation height of the passive support unit formed by the positive stiffness element and the negative stiffness element which are connected in parallel and the linear actuator.
Further, the positive stiffness element is a metal coil spring, rubber or an air spring; the negative stiffness element is a magnetic negative stiffness mechanism, a pre-compression spring negative stiffness mechanism, a compression bar negative stiffness or cam-roller-spring negative stiffness mechanism, the guide mechanism is an air-floating guide rail, and the displacement sensor is a grating ruler displacement sensor, a laser displacement sensor, an eddy current sensor, a Hall sensor or an LVDT displacement sensor.
Further, the linear motion mechanism is a lead screw linear motion mechanism, a pneumatic linear motion mechanism, a hydraulic linear motion mechanism, a gear-rack linear motion mechanism, a winch lifting mechanism, a chain transmission mechanism, a synchronous belt transmission mechanism or a linear motor, and the linear actuator is a voice coil motor, a lorentz motor, a linear motor or a reluctance motor.
According to a second aspect of the present invention, there is also provided a method for implementing variable mass load micro-low gravity environment simulation by the apparatus as described above, comprising the steps of:
s1: placing the load equipment to be simulated above the top plate in a ground surface gravity environment, and adjusting the force application magnitude of the linear actuator to be the gravity of the load equipment in a target low gravity environment, so that the passive support unit bears the residual gravity of the load equipment;
s2: the height of the passive supporting unit is changed to be the stroke midpoint of the passive supporting unit through the height adjusting mechanism until the rigidity of the passive supporting unit is zero;
s3: starting a linear motion mechanism, moving the passive support unit in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, and simultaneously converging the height change of the passive support unit to keep the load equipment to have the acceleration under the target micro-gravity environment;
s4: starting a linear actuator, exciting the top plate in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, counteracting wave power caused by deformation of the passive support unit, and accurately keeping the load equipment to have acceleration in a zero gravity environment;
s5: according to the mass change information of the load equipment monitored by the load mass sensing unit, the mass change information is fed back to the driving control module through the load equipment controller, the excitation of the linear actuator to the top plate in the gravity direction is changed through the driving control module, the fluctuating force caused by the mass change of the load equipment is counteracted, and the load equipment is kept to have the acceleration in the zero gravity environment.
In general, the above technical solutions conceived by the present invention are used to achieve the following beneficial effects compared to the prior art:
(1) the load quality sensing unit monitors real-time change of load quality of the load equipment caused by active operation or passive change in real time, and enables the linear actuator to offset fluctuating force caused by the real-time change of the load equipment quality according to the change, so that the precision of a simulation test is improved. The passive supporting unit is used for supporting the load equipment, the formed passive system is high in response speed and almost free of time delay while zero gravity environment simulation is achieved, the passive supporting unit supports the load equipment through the positive stiffness element, the negative stiffness element offsets the stiffness of the positive stiffness element at a balance position, the passive supporting unit can have large load, the stiffness is in a quasi-zero state, and the precision of a simulation test is further improved.
(2) Compared with the air cylinder mechanism in the existing gravity simulation device, the linear motion mechanism has a larger displacement range and a stroke reaching the meter level, so that the supporting device can realize high-fidelity vertical low-gravity environment simulation in a large stroke. The passive support unit, the linear actuator and the guide mechanism are all friction loss-free components, so that the device has higher sensitivity and resolution for the dynamic behavior simulation of the load equipment.
(3) In the simulation test, the driving control module drives the linear actuator and the linear motion mechanism according to the received signal information of the displacement sensor and the load quality sensing unit, so that the fluctuating force existing in the test process is counteracted, and the corresponding speed and precision of the simulation test are improved.
Drawings
FIG. 1 is a schematic diagram of the internal structure of a low gravity environment simulator for variable mass loading according to an embodiment of the present invention;
fig. 2 is a flow chart of a method for realizing the simulation of the micro-low gravity environment with variable mass load by adopting the device of the embodiment of the invention.
In the drawings are labeled: the device comprises a top plate 1, a bottom plate 2, a positive stiffness element 3, a negative stiffness element 4, a linear actuator 5, a guide mechanism 6, a height adjusting mechanism 7, a displacement sensor 8, a linear motion mechanism 9, a driving control module 10, a base 11, a load mass sensing unit 12, a gas pressure sensor 12a and a mass flowmeter 12 b.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Fig. 1 is a schematic diagram of an internal structure of a micro low-gravity environment simulation device for variable mass loads according to an embodiment of the present invention, and the internal structure of the micro low-gravity environment simulation device includes a near-zero stiffness supporting component, a motion following component and a load device mass monitoring component 3, the near-zero stiffness supporting component and the motion following component are independent from each other, the near-zero stiffness supporting component and the motion following component are connected up and down to form a series structure, the load device mass monitoring component 3 is connected with the variable mass load, and the variable mass load is fixed or hinged on the near-zero stiffness supporting component.
Specifically, the near-zero stiffness supporting assembly comprises a top plate 1, a bottom plate 2, a positive stiffness element 3, a negative stiffness element 4, a guide mechanism 6, a linear actuator 5 and a height adjusting mechanism 7, and the motion following assembly comprises a displacement sensor 8, a linear motion mechanism 9, a drive control module 10 and a base 11. The load device quality monitoring assembly 3 includes a load device controller and a load quality sensing unit 12.
Roof 1 and bottom plate 2 level setting and parallel to each other, roof 1 and bottom plate 2 are square metal bearing plate, roof 1 is used for fixed variable mass load (also called load equipment) of waiting to simulate. The positive stiffness element 3 and the negative stiffness element 4 are connected in parallel to form a passive supporting unit, two ends of the passive supporting unit are respectively and fixedly connected with the top plate 1 and the top plate 2, the passive supporting unit plays a role of supporting load equipment to be simulated and rapidly makes displacement response when the load equipment is subjected to external force, the bearing capacity of the passive supporting unit is larger than the gravity borne by the load equipment to be simulated, and the rigidity of the passive supporting unit is as small as possible. The positive stiffness element 3 is a metal spiral spring and is characterized by having large bearing capacity and reasonable low stiffness characteristic, and the negative stiffness element 4 is a non-contact friction-free magnetic negative stiffness mechanism and is used for offsetting the stiffness of the positive stiffness element 3 at a balance position so that the stiffness of the passive support unit is in a quasi-zero state.
The positive stiffness element 3 has a stiffness value kp(kp> 0), the negative stiffness element 4 has a stiffness value kn(kn< 0), the combined stiffness value of the two must be made positive and as small as possible within the effective working stroke range, i.e. ks＝kp+knGreater than 0, wherein the combined stiffness value satisfies 0.001kp＜ks＝kp+kn＜0.1kp. In one embodiment of the invention, the number of positive stiffness elements 3 and of negative stiffness elements 4 is four, and these positive stiffness elements 3 and negative stiffness elements 4 are arranged in a square.
The linear actuator 5 is connected with the passive supporting unit in parallel, is arranged between the top plate 1 and the bottom plate 2 and is a non-contact voice coil motor, the linear actuator 5 comprises a linear actuator rotor and a linear actuator stator, the linear actuator 5 is fixedly connected with the top plate 1 and the bottom plate 2 respectively, the linear actuator stator connected with a cable is connected with the bottom plate 2, and disturbance influence of the cable on the top plate 1 in the system movement process is reduced as much as possible.
The guide mechanism 6 is arranged between the top plate 1 and the bottom plate 2, plays a role in guiding in the moving direction, and preferably takes a non-contact and frictionless guide mechanism as a preferable mode, the guide mechanism 6 adopts an air-float guide rail, and has the function of frictionless guiding in the moving direction, and the relative torsion between the top plate 1 and the bottom plate 2 is limited, so that the mutual interference of parts is avoided. The air-floatation guide rail stator of the guide mechanism 6 connected with the air supply pipeline is fixedly arranged on the bottom plate 2, and the air-floatation guide rail rotor is fixedly arranged on the top plate 1, so that the disturbance influence of the pipeline on the top plate 1 in the system movement process is avoided.
One end of the height adjusting mechanism 7 is fixed on the bottom plate 2, and the other end of the height adjusting mechanism is matched with the positive rigidity element 3 and is used for adjusting the installation height of the positive rigidity element 3 in the supporting assembly. For example, the number of the height adjusting mechanisms 7 is four, and the height adjusting mechanisms are symmetrically distributed around the bottom plate 2. The height adjusting mechanism 7 comprises a height adjusting nut and a stud, the height adjusting nut and the stud are in the same specification, the height adjusting nut penetrates through the stud and is in contact with the bottom of the positive stiffness element 3, the stud is fixedly connected with the bottom plate 2 and is not in contact with the positive stiffness element 3, the height adjusting nut 7a is rotated to adjust the installation height of the correspondingly connected positive stiffness element 3, namely the relative height of the linear actuator 5 and the passive support unit is adjusted, so that the difference of the middle point of the effective working strokes of the two is as small as possible, and 1/10 which is not more than 1mm or the minimum working stroke of the two is preferably used. In one embodiment of the invention, the height adjustment mechanisms 7 are four in number, are connected in a fitting manner with the positive stiffness element 3 and are arranged in a square manner. The guide mechanism 6 comprises an air floatation guide rail rotor and an air floatation guide rail stator, is square and is arranged in the center of the bottom plate 2.
The driving module 10 receives a feedback signal of the displacement sensor 8, controls the linear actuator 5 and the linear motion mechanism 9 to move, ensures that the relative displacement between the top plate 1 and the bottom plate 2 is constant, enables the rigidity of the passive supporting unit to be close to zero and the deformation to be close to zero, and enables the supporting force of the top plate 1 to the load equipment to fluctuate to be close to zero so as to realize the simulation of the vertical zero gravity of the load equipment. One end of the base 11 is fixedly connected with the linear motion mechanism 9, and the other end is arranged on a foundation or a similar external foundation.
The load equipment quality monitoring assembly 3 comprises a load equipment controller and a load quality sensing unit 12, wherein the load equipment controller is connected with the load quality sensing unit, the load equipment sensing unit is used for monitoring the mass consumption of the load equipment in real time and transmitting a signal of the mass consumption to the load equipment controller, the load equipment controller is also connected with a driving control module, in operation, when the mass of the load equipment changes, the mass consumption of the load equipment is monitored in real time through the load quality sensing unit and is transmitted to the load equipment controller, the load equipment controller generates a feed-forward force signal for mass change compensation, a linear actuator compensates the load equipment in real time through a top plate according to the feed-forward force signal, and the passive support unit, the linear actuator and the motion following assembly cooperate together.
Specifically, the load mass sensing unit 12 is mounted on the load device and is used for monitoring the mass change of the load device. The load mass sensing unit 12 comprises a gas pressure sensor 12a and a mass flow meter 12b, wherein the gas pressure sensor 12a is installed inside the whole load equipment pneumatic system, the number of the gas pressure sensors is at least one, and the gas pressure sensors are used for monitoring the change of the pressure in the load equipment pneumatic system to calculate the gas mass consumption, and the mass flow meter 12b is installed in the whole load equipment gas injection pipeline, the number of the mass flow meters is at least one, and the mass flow meters are used for directly monitoring the gas mass consumption sprayed out of each gas nozzle of the load equipment. The load mass sensing unit 12 is a lighter flexible cable to avoid disturbing effects on the zero-gravity (or low-gravity) environmental simulation of the load device.
Fig. 2 is a schematic flow chart of a method for implementing variable-mass-load micro-low-gravity environment simulation by using the apparatus according to the embodiment of the present invention, and as can be seen, the method mainly includes the following steps:
s1: placing the load equipment to be simulated above the top plate in a ground surface gravity environment, and adjusting the force application magnitude of the linear actuator to be the gravity of the load equipment in a target low gravity environment, so that the passive support unit bears the residual gravity of the load equipment;
s2: the height of the passive supporting unit is changed to be the stroke midpoint of the passive supporting unit through the height adjusting mechanism until the rigidity of the passive supporting unit is zero;
s3: starting a linear motion mechanism, moving the passive support unit in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, and simultaneously converging the height change of the passive support unit to ensure that the load equipment has the acceleration under the target micro-gravity environment;
s4: starting a linear actuator, applying an acting force to the top plate in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, offsetting wave power caused by the deformation of the passive support unit, and accurately keeping the load equipment to have acceleration in a zero gravity environment;
s5: according to the mass change information of the load equipment monitored by the load mass sensing unit, the mass change information is fed back to the driving control module through the load equipment controller, the acting force of the linear actuator on the top plate in the gravity direction is changed through the driving control module, the fluctuating force caused by the mass change of the load equipment is counteracted, and the load equipment has the acceleration in the zero gravity environment.
In practical engineering application, the method and the process for simulating by using the zero-gravity environment simulation device are as follows:
the total mass of the structures such as the top plate 1 fixedly connected with the load measuring equipment and the zero gravity environment simulation device is m, and the gravity acceleration of the earth surface is g. It is assumed that a zero gravity environment has to be simulated on the earth surface, and that the simulated initial condition is that the initial velocity of the load equipment is upsilon0。
The method comprises the following steps: locking the linear motion mechanism 9, and turning off the linear actuator 5 or controlling the output force to be zero so that the magnitude of the action force exerted on the top plate 1 by the linear actuator 5 is FE0Mg' so that the force exerted by the passive bearing unit on the top plate 1 is of magnitude FK-m (g-g'), whereby the load device to be simulated is statically balanced under a gravitational field g; the height of the top plate 1 relative to the bottom plate 2 in a static balance state is enabled to be as close to the stroke middle point (design zero point) of the passive bearing unit as possible through matching adjustment of the height adjusting mechanism 7 and the linear actuator 5, and the height h of the top plate 1 relative to the bottom plate 2 in the static balance state is counted0；
Step two: the output force of the linear actuator 5 is changed, so that the load equipment moves in an accelerated manner to the initial velocity upsilon simulated in the zero gravity environment0(ii) a In the acceleration process, the linear motion mechanism 9 is started simultaneously, so that the motion trail and the motion speed of the bottom plate 2 and the top plate 1 are kept as consistent as possible; when the moving speeds of the bottom plate 2 and the top plate 1 are equal to the set initial speed v0When the error is less than the allowable value, the height of the top plate 1 relative to the bottom plate 2 is reset to h0. When initial velocity upsilon is required0When 0, step two may be omitted.
Step three: the force output state of the linear actuator 5 and the motion state of the linear motion mechanism are changed so that the resultant force exerted on the top plate 1 by the linear actuator 5 and the passive support unit at any time t in the simulation period satisfies F as much as possibleE(t)+FK(t) ═ m (g-g '), so that the resultant force of gravity borne by the simulation equipment (including rigid fixed structures such as the top plate 1) and the supporting force of the simulation device is as close to F (t) ═ mg ', namely, the dynamic behavior and the gravity acceleration of the load equipment on the earth surface are accurate in the gravity environment with g ' of the dynamic behavior and the gravity acceleration under the action of the earth gravity and the supporting force of the zero gravity environment simulation deviceAnd (5) the consistency is achieved.
In order to achieve the state described in the third step, one alternative is to close the linear actuator or control the output of the linear actuator to be zero, detect the height change of the top plate relative to the bottom plate in real time by using the displacement sensor, transmit the detection signal to the linear motion mechanism driving control module in the motion following assembly, generate the motion command of the linear motion mechanism by the linear motion mechanism driving control module, and control the motion platform to follow the equipment frame to move synchronously according to a proper control strategy, that is, to make the relative height change amount Δ h (t) of the equipment frame relative to the supporting base as much as possible (h (t) -h0When the force approaches zero, the supporting force of the low gravity environment simulation device (the supporting force of the passive supporting unit) fluctuates by Δ f (t) ks·Δh(t)＝(kp+kn)·[h(t)-h0]。
In order to achieve the state described in the third step, a preferable scheme is that the displacement sensor is used for detecting the height change between the top plate and the bottom plate in real time, on one hand, the detection signal is transmitted to the linear actuator driving control module, and the linear actuator is controlled to output power according to the following rules: fE(t)＝-ΔF(t)＝-ks·Δh(t)＝-(kp+kn)·[h(t)-h0]That is, the linear actuator generates the supporting force fluctuation value with equal magnitude and opposite direction with the passive supporting unit, so that the dynamic behavior of the load equipment on the earth surface is precisely consistent with that of the load equipment in the environment with the gravity acceleration g' under the action of the earth gravity and the supporting force of the low gravity environment simulation device.
In order to achieve the state described in the third step, a preferable scheme is that, on one hand, a variation curve of the supporting force of the passive supporting unit in the near-zero stiffness supporting assembly along with the relative height of the top plate and the bottom plate (called passive supporting unit supporting force nonlinear characteristic for short) is accurately measured in advance, and on the other hand, a variation curve of the thrust constant of the linear actuator in the near-zero stiffness supporting assembly along with the relative height of the top plate and the bottom plate (called active force application unit thrust nonlinear characteristic for short) is accurately measured in advance; then, in step three, based on the real-time detection, the relative height variation quantity delta h (t) ═ h (t) — h0According to the quiltAccurate determination of real-time supporting force of passive supporting unit relative to ideal supporting force F based on nonlinear characteristic of supporting force of movable supporting unitKAccording to the deviation of-m (g-g'), a compensation force control command of the linear actuator is determined according to the thrust nonlinearity of the linear actuator, the linear actuator is used for generating a precise compensation force, and the linear actuator is connected with the passive support unit in parallel, so that the resultant force of the support forces meets F preciselyE(t)+FKAnd (t) — m (g-g '), so that a micro low gravity environment with the gravity acceleration of g' is accurately simulated.
Step four: estimating the mass consumption Deltam of the load equipment according to the active operation instruction of the load equipment1(t) the mass consumption can be gas mass consumption caused by the gas injection of the load equipment or other active operation which can cause mass change. Generation of mass-change compensated feed-forward force F by load device controller1(t)＝-Δm1(t) g signal, feeding back the signal to the drive module 10, and controlling the output of the linear actuator 5, i.e. F, by the drive module 10E(t)＝-ΔF(t)+F1(t)＝-ks·Δh(t)-Δm1(t)·g。
The load quality change is directly or indirectly monitored in real time according to the load quality sensing unit 12, and more accurate load equipment mass change delta m is obtained2(t), transmitting the monitoring signal to the load equipment controller, fusing the monitoring signal of the load quality sensing unit by the load equipment controller, automatically analyzing and integrating the monitoring signal through a certain criterion, and generating a feedforward force F (t) - Δ m for compensating the quality change2(t) g signal to correct the linear actuator 5 output, i.e. FE(t)＝-ΔF(t)+F2(t)＝-ks·Δh(t)-Δm2(t) · g, so as to more accurately simulate the micro-low gravity environment with the gravity acceleration g'.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A micro-low gravity environment simulation device for variable mass load is characterized by comprising a near-zero stiffness supporting component, a motion following component and a load equipment mass monitoring component (3), wherein the near-zero stiffness supporting component and the motion following component are mutually independent, the near-zero stiffness supporting component and the motion following component are connected up and down to form a series structure, the load equipment mass monitoring component (3) is connected with the variable mass load, the variable mass load is fixed or hinged on the near-zero stiffness supporting component,
the near-zero stiffness supporting assembly comprises a top plate (1), a bottom plate (2), a passive supporting unit and a linear actuator (5), wherein the passive supporting unit and the linear actuator are arranged between the top plate and the bottom plate, the top plate (1) and the bottom plate (2) are parallel to each other, the top plate is used for bearing load equipment to be simulated, the bearing capacity of the passive supporting unit is greater than the gravity borne by the load equipment to be simulated, the motion following assembly is connected with the bottom plate (2) and used for providing excitation for the bottom plate so as to enable the bottom plate to follow the top plate to generate preset speed and motion,
the load equipment quality monitoring assembly (3) comprises a load equipment controller and a load quality sensing unit, wherein the load equipment controller is connected with the load quality sensing unit, the load equipment sensing unit is used for monitoring the mass consumption of the load equipment in real time and transmitting a signal of the mass consumption to the load equipment controller, the load equipment controller is also connected with a linear actuator by a signal,
during work, when the mass of the load equipment changes, the mass consumption of the load equipment is monitored in real time through the load mass sensing unit, signals of the mass consumption are transmitted to the load equipment controller, the load equipment controller generates a mass change compensation feed-forward force signal, the linear actuator compensates the load equipment in real time through the top plate according to the feed-forward force signal, the passive support unit, the linear actuator and the motion following assembly cooperate together to provide a celestial sphere surface or space stress environment with the gravity acceleration g 'for the load equipment to be simulated, wherein the gravity acceleration g is greater than or equal to 0 and smaller than g' < g, and g is the gravity acceleration of the earth surface.
2. The low gravity environment simulation apparatus for variable mass load according to claim 1, wherein the load mass sensing unit (12) comprises a gas pressure sensor (12a) and a mass flow meter (12b), the gas pressure sensor (12a) is installed inside the load equipment gas tank and has at least one for monitoring the change of the pressure inside the load equipment gas tank so as to calculate the gas mass consumption, and the mass flow meter (12b) is installed in the load equipment gas injection pipeline and has at least one for directly monitoring the gas mass consumption jetted from each gas nozzle of the load equipment.
3. A low gravity environment simulation apparatus for variable mass loads according to claim 2, wherein the gas pressure sensor (12a) and the mass flow meter (12b) are connected to the load device by a flexible cable to avoid disturbing effects on zero gravity or low gravity environment simulation of the load device.
4. The simulation apparatus of claim 3, wherein the gas pressure sensor monitors the pressure change in the gas tank of the load device or in the pneumatic system in real time, and calculates the gas consumption, the mass flow meter monitors the gas consumption sprayed from each gas nozzle in real time, and transmits the monitoring signal to the load device controller, the load device controller fuses the gas consumption fed back by the gas pressure sensor and the mass flow meter, and performs automatic analysis according to a set criterion to obtain a precise load device mass change, and the load device controller generates a feed-forward force signal for compensating the mass change according to the obtained mass consumption, and outputs a command to control the output of the linear actuator.
5. A low gravity environment simulator for varying mass loads according to claim 4, wherein a plurality of gas pressure sensors (12a) are arranged at different positions throughout the load device, and a plurality of mass flow meters (12b) are also arranged at different positions throughout the gas injection line of the load device.
6. A low gravity environment simulation device for variable mass loads according to claim 5, wherein the near zero stiffness bearing assembly further comprises a guiding mechanism (6), the motion following assembly comprises a displacement sensor (8), a linear motion mechanism (9), a driving control module (10) and a base (11), wherein the passive bearing unit comprises a positive stiffness element (3) and a negative stiffness element (4), the positive stiffness element (3) and the negative stiffness element (4) are connected in parallel with each other, the positive stiffness element (3) and the negative stiffness element (4) are arranged between the top plate and the bottom plate, the passive bearing unit is used for passively supporting the gravity of the load equipment, the guiding mechanism (6) is also arranged between the top plate and the bottom plate and simultaneously connects the top plate and the bottom plate, the guiding mechanism (6) is used for frictionless guiding in the motion direction and limiting the relative torsion between the top plate 1 and the bottom plate (2), the mutual interference of parts is avoided;
the displacement sensor (8) is arranged between the top plate (1) and the bottom plate (2), the upper end of the displacement sensor is connected with the top plate (1), and the lower end of the displacement sensor is connected with the bottom plate (2) and used for monitoring the height change of the passive supporting unit; the linear motion mechanism (9) is connected below the bottom plate (2) so that the passive support unit can perform preset movement in the gravity direction of the load equipment; the driving control module (10) is respectively electrically connected with the displacement sensor (8), the linear motion mechanism (9), the linear actuator and the load equipment controller, and is used for driving and controlling the linear motion mechanism (9) according to the received signal information of the displacement sensor (8) and also used for controlling the linear actuator to move according to the signal of the load equipment controller; the top surface of the base (11) is connected with the fixed end of the linear motion mechanism (9), and the bottom surface of the base is fixedly connected to an external foundation;
when the device works, the drive control module (10) receives feedback signals of the displacement sensor (8) and the load equipment controller, controls the linear actuator (5) and the linear motion mechanism (9) to move, ensures that the relative displacement between the top plate (1) and the bottom plate (2) is constant, enables the rigidity of the passive supporting unit to be close to zero and the deformation to be close to zero, generates mass change compensation for the mass consumption of variable-mass load equipment, and enables the supporting force fluctuation of the top plate (1) to the load equipment to be close to zero.
7. A low gravity environment simulating assembly for variable mass loads according to claim 5 wherein the linear actuator (5) comprises a stator and a mover, the stator is connected to the base plate (2), the mover is connected to the top plate (1), the linear actuator (5) and the passive bearing unit are connected in parallel, and the relative height of the linear actuator (5) and the relative height of the passive bearing unit are adjustable such that the difference in height between the mid-points of the effective working strokes is no more than 1mm or no more than 1/10 of the minimum working stroke.
8. The micro-low gravity environment simulation device for variable mass loads according to claim 6, wherein a height adjusting mechanism (7) is connected to the positive stiffness element (3) in a matching manner, the height adjusting mechanism (7) is used for adjusting the relative installation height of the passive support unit and the linear actuator (5), the height adjusting mechanism (7) comprises a nut and a stud, the nut penetrates through the stud and is connected with the positive stiffness element (3) in a matching manner, the stud is fixedly connected with the base plate (2), and the relative installation height of the passive support unit and the linear actuator (5) formed by connecting the positive stiffness element (3) and the negative stiffness element (4) in parallel can be adjusted by rotating the nut.
9. A micro low gravity environment simulating assembly for varying mass loads according to claim 7 characterised in that the positive stiffness element (3) is a metal coil spring, rubber or air spring; the negative stiffness element (4) is a magnetic negative stiffness mechanism, a pre-compression spring negative stiffness mechanism, a compression bar negative stiffness or a cam-roller-spring negative stiffness mechanism, the guide mechanism (6) is an air floatation guide rail, the displacement sensor (8) is a grating ruler displacement sensor, a laser displacement sensor, an eddy current sensor, a Hall sensor or an LVDT displacement sensor,
the linear motion mechanism (9) is a lead screw linear motion mechanism, a pneumatic linear motion mechanism, a hydraulic linear motion mechanism, a gear-rack linear motion mechanism, a winch lifting mechanism, a chain transmission mechanism, a synchronous belt transmission mechanism or a linear motor, and the linear actuator (5) is a voice coil motor, a Lorentz motor, a linear motor or a reluctance motor.
10. Method for realising variable mass loaded micro low gravity environment simulation using the device according to any of the claims 1-9, characterised in that it comprises the following steps:
s1: placing the load equipment to be simulated above the top plate in a ground surface gravity environment, and adjusting the force application magnitude of the linear actuator to be the gravity of the load equipment in a target low gravity environment, so that the passive support unit bears the residual gravity of the load equipment;
s2: the height of the passive supporting unit is changed to be the stroke midpoint of the passive supporting unit through the height adjusting mechanism until the rigidity of the passive supporting unit is zero;
s3: starting a linear motion mechanism, moving the passive support unit in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, and simultaneously converging the height change of the passive support unit to ensure that the load equipment has the acceleration under the target micro-gravity environment;
s4: starting a linear actuator, applying an acting force to the top plate in the gravity direction according to the height change information of the passive support unit monitored by the displacement sensor, offsetting wave power caused by the deformation of the passive support unit, and accurately keeping the load equipment to have acceleration in a zero gravity environment;
s5: according to the mass change information of the load equipment monitored by the load mass sensing unit, the mass change information is fed back to the driving control module through the load equipment controller, the acting force of the linear actuator on the top plate in the gravity direction is changed through the driving control module, the fluctuating force caused by the mass change of the load equipment is counteracted, and the load equipment has the acceleration in the zero gravity environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111350488.7A CN113928605B (en) | 2021-11-15 | 2021-11-15 | Micro-low gravity environment simulation device and method for variable mass load |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111350488.7A CN113928605B (en) | 2021-11-15 | 2021-11-15 | Micro-low gravity environment simulation device and method for variable mass load |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113928605A true CN113928605A (en) | 2022-01-14 |
| CN113928605B CN113928605B (en) | 2023-10-24 |
Family
ID=79286666
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111350488.7A Active CN113928605B (en) | 2021-11-15 | 2021-11-15 | Micro-low gravity environment simulation device and method for variable mass load |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113928605B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114162360A (en) * | 2022-02-11 | 2022-03-11 | 清华大学 | Adjusting assembly and simulating device of somatosensory micro-low gravity simulating device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5310157A (en) * | 1989-08-16 | 1994-05-10 | Minus K Technology, Inc. | Vibration isolation system |
| US20050230557A1 (en) * | 2003-12-30 | 2005-10-20 | Canadian Space Agency | Zero-G emulating testbed for spacecraft control system |
| KR20070061147A (en) * | 2005-12-08 | 2007-06-13 | 한국전자통신연구원 | Weight-adaptive gravity compensating device |
| CN103279595A (en) * | 2013-04-27 | 2013-09-04 | 上海卫星工程研究所 | Method for designing quasi-zero stiffness nonlinear suspension system |
| CN104158431A (en) * | 2014-08-05 | 2014-11-19 | 中国空间技术研究院 | Electrostatic suspension type space-based super quiescent platform system |
| CN113525733A (en) * | 2021-08-16 | 2021-10-22 | 哈尔滨工业大学 | Six-degree-of-freedom microgravity test system with double-layer structure |
-
2021
- 2021-11-15 CN CN202111350488.7A patent/CN113928605B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5310157A (en) * | 1989-08-16 | 1994-05-10 | Minus K Technology, Inc. | Vibration isolation system |
| US20050230557A1 (en) * | 2003-12-30 | 2005-10-20 | Canadian Space Agency | Zero-G emulating testbed for spacecraft control system |
| KR20070061147A (en) * | 2005-12-08 | 2007-06-13 | 한국전자통신연구원 | Weight-adaptive gravity compensating device |
| CN103279595A (en) * | 2013-04-27 | 2013-09-04 | 上海卫星工程研究所 | Method for designing quasi-zero stiffness nonlinear suspension system |
| CN104158431A (en) * | 2014-08-05 | 2014-11-19 | 中国空间技术研究院 | Electrostatic suspension type space-based super quiescent platform system |
| CN113525733A (en) * | 2021-08-16 | 2021-10-22 | 哈尔滨工业大学 | Six-degree-of-freedom microgravity test system with double-layer structure |
Non-Patent Citations (2)
| Title |
|---|
| 唐锐;黄海;黄舟;: "基于准零刚度技术的微重力模拟悬吊装置设计与试验研究", 航天器环境工程, no. 02, pages 222 - 228 * |
| 路波;陶国良;刘昊;: "零重力模拟气动悬挂系统的开发及关键技术", 浙江大学学报(工学版), no. 05, pages 890 - 896 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114162360A (en) * | 2022-02-11 | 2022-03-11 | 清华大学 | Adjusting assembly and simulating device of somatosensory micro-low gravity simulating device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113928605B (en) | 2023-10-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7281431B2 (en) | Velocity feedback compensation for force control systems | |
| US7469885B2 (en) | Compliant coupling force control system | |
| CN103413489B (en) | Torque servo control loading load simulator | |
| CN113928603B (en) | Six-degree-of-freedom space microgravity simulation device and control method | |
| CN110413015A (en) | Micro- ox magnitude microthrust dynamic testboard and test method based on closed-loop control | |
| RU2478924C1 (en) | Measuring device of impulse reactive thrust of low thrust liquid propellant engine | |
| CN104803015B (en) | Large lift air supporting high-precision gravity relief arrangement | |
| CN113525733B (en) | Six-degree-of-freedom microgravity test system with double-layer structure | |
| CN107458630B (en) | Suspension point cross-scale tracking method for suspension type active gravity compensation system | |
| CN113928605A (en) | Micro-low gravity environment simulation device and method for variable mass load | |
| CN105109713B (en) | The vertical subsystem control method of gravity compensation based on sliding-mode surface | |
| CN112340071A (en) | Large-scale heavy-load air floatation suspension expansion test device and test method | |
| CN113942667B (en) | Micro-low gravity environment simulation method and device | |
| CN110501114B (en) | Three-dimensional force sensor dynamic characteristic calibration device and method | |
| CN113942666B (en) | Near-zero stiffness supporting device for zero gravity environment simulation | |
| US3052120A (en) | Planar motion mechanism and system | |
| CN102072796B (en) | Solar battery array dynamic-measurement system | |
| CN116620576A (en) | Zero gravity environment simulation device and method capable of compensating additional mass inertia force | |
| CN109709822B (en) | Whole-satellite ground semi-physical test device for large-scale flexible spacecraft | |
| Neumann et al. | The 250mN Thrust Balance for the DLR Goettingen EP Test Facility | |
| CN115096496B (en) | Method for performing spatial six-dimensional force decoupling measurement by adopting cable drive mechanism | |
| CN112362231B (en) | In-situ loading calibration system and method for three-component force measuring device | |
| KIENHOLZ et al. | Very low frequency suspension systems for dynamic testing | |
| RU2692591C1 (en) | Traction measuring device for testing liquid thrust low-thrust engines in stationary mode of operation | |
| CN111638721A (en) | Spacecraft three-super-control full-link disturbance transmission verification system and verification method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |