WO2006001691A1 - Long stroke position actuator with high load capacity and manometer resolution - Google Patents

Long stroke position actuator with high load capacity and manometer resolution Download PDF

Info

Publication number
WO2006001691A1
WO2006001691A1 PCT/NL2005/000437 NL2005000437W WO2006001691A1 WO 2006001691 A1 WO2006001691 A1 WO 2006001691A1 NL 2005000437 W NL2005000437 W NL 2005000437W WO 2006001691 A1 WO2006001691 A1 WO 2006001691A1
Authority
WO
WIPO (PCT)
Prior art keywords
actuator
pneumatic
former
load
positioning
Prior art date
Application number
PCT/NL2005/000437
Other languages
French (fr)
Inventor
Hubertus Leonardus Mathias Marie Janssen
Maurice Anton Jaques Teuwen
V. Bartholomeus Catharina Thomas Bree
Rudolf Geurink
Original Assignee
Janssen Precision Engineering B.V.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Janssen Precision Engineering B.V. filed Critical Janssen Precision Engineering B.V.
Publication of WO2006001691A1 publication Critical patent/WO2006001691A1/en

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/18—Mountings, adjusting means, or light-tight connections, for optical elements for prisms; for mirrors
    • G02B7/182—Mountings, adjusting means, or light-tight connections, for optical elements for prisms; for mirrors for mirrors
    • G02B7/183—Mountings, adjusting means, or light-tight connections, for optical elements for prisms; for mirrors for mirrors specially adapted for very large mirrors, e.g. for astronomy, or solar concentrators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08—Characterised by the construction of the motor unit
    • F15B15/088—Characterised by the construction of the motor unit the motor using combined actuation, e.g. electric and fluid actuation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20538—Type of pump constant capacity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40515—Flow control characterised by the type of flow control means or valve with variable throttles or orifices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41527—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/42—Flow control characterised by the type of actuation
    • F15B2211/426—Flow control characterised by the type of actuation electrically or electronically
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/455—Control of flow in the feed line, i.e. meter-in control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/46—Control of flow in the return line, i.e. meter-out control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/625—Accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/63—Electronic controllers
    • F15B2211/6303—Electronic controllers using input signals
    • F15B2211/6336—Electronic controllers using input signals representing a state of the output member, e.g. position, speed or acceleration
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/665—Methods of control using electronic components
    • F15B2211/6654—Flow rate control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7052—Single-acting output members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/765—Control of position or angle of the output member

Definitions

  • the invention of a long stroke position actuator with high load capacity and nanometer resolution is based on a combined electromagnetic and pneumatic actuator where the pneumatic actuator takes care of the high force and low frequency part and the electromagnetic actuator takes care of the low force but high frequency part of the disturbance forces. Both actuators are combined in such a way that the resulting stiffness in force direction is equivalent to the sum of the stiffnesses of both actuators.
  • the invention concerns a position actuator able to avoid contamination and internal friction leading to high reliability and to optimize the overall positioning performance by applying adequate control strategies. Especially the use of this position actuator in a positioning and guiding system for large segmented mirror telescopes will be shown. Also a possibility to avoid the complex and heavy whiff 1 etre e s , mostly used in telescopes to support the mirrors, will be presented.
  • the above stated objectives can be fulfilled by operation of the pneumatic actuator with low stiffness for low frequency high load positioning demands and the magnetic actuator with high stiffness for high frequency positioning demands in a parallel way.
  • the pneumatic actuator with low stiffness for low frequency high load positioning demands and the magnetic actuator with high stiffness for high frequency positioning demands in a parallel way.
  • only elements without friction are used.
  • the application of a completely closed gas supply and exhaust system is used in order to obtain high reliability by avoiding internal contamination.
  • Fig.l is a schematic drawing of the system according to the invention
  • Fig.2 is a schematic drawing of the system according to the invention specially adapted for positioning large optical mirrors
  • Fig.3 is a schematic drawing of a system with a three actuator support of a large optical mirror, where the position actuator and guiding are integrated
  • Fig.4 is a schematic top view of figure 3
  • Fig.5 is a schematic drawing of an application in a multi segment mirror telescope with gas supply layout.
  • Fig.6 is a block diagram of a positioning system according to the present invention.
  • the pneumatic actuator chamber 15 comprises a bellows defined by the elastic element 2, a side/bottom wall 1 and moveable lid 3 which is airtight connected to the actuator rod 4.
  • One gas supply line with a pressure higher than required in the inner chamber is connected via the input 13 to a buffer chamber 12 and by means of a valve 14 to the chamber 15, while an other gas supply with a pressure lower than required in the inner chamber is connected via the output 9 to a buffer chamber 10 and by means of a valve 8 to the chamber 15. Controlling the flow through each valve makes it possible to control the amount of gas in the chamber 15 and therefore also the position and or applicable force of output rod 4.
  • the magnetic actuator comprising the magnet 5 and coil 7 is positioned in such a way that the resulting stiffness of the position actuator is the sum of the pneumatic and the magnetic actuator.
  • the magnetic actuator is used in order to make position corrections with relative low force but high bandwidth superimposed on the position of the pneumatic actuator, which requires a magnetic actuator with a stroke larger than the stroke of the pneumatic actuator.
  • To obtain maximal stiffness in the accurate positioning loop the magnetic actuator is directly connecting the frame 11 with the positioning rod 4.
  • an elastic guiding 6 is foreseen.
  • the pneumatic actuator chamber 16 comprises a bellows defined by the elastic element 4, a side/bottom wall 5 and moveable support 3 which supports the optical mirror 1.
  • One gas supply line with a pressure higher than required in the inner chamber is connected via the input 14 to a buffer chamber 13 and by means of a valve 15 to the chamber 16, while an other gas supply with a pressure lower than required in the inner chamber is connected via the output 10 to a buffer chamber 11 and by means of a valve 9 to the chamber 16.
  • Controlling the flow through each valve makes it possible to control the amount of gas in the chamber 16 and therefore also the position and or applicable force on the optical mirror 1.
  • the magnetic actuator comprising magnet 6 and coil 8 is positioned in such a way that the resulting stiffness of the position actuator is the sum of the pneumatic and the magnetic actuator.
  • the magnetic actuator is used to make position corrections with relative low force but high bandwidth superimposed on the position of the pneumatic actuator, which requires a magnetic actuator with a stroke larger than the stroke of the pneumatic actuator.
  • the magnetic actuator is directly connecting the frame 12 with the optical mirror 1.
  • an elastic guiding 7 is foreseen.
  • FIG 3 and figure 4 a system with a three actuator support of a large optical mirror is schematically shown.
  • An optical mirror 1 is supported by three position actuators 2 as described in figure 2.
  • the optical mirror will be supported on a large surface by an elastic medium 3 which is self aligning with respect to the optical mirror.
  • an elastic element 4 like three folded leaf springs, attached with interface 9 to the optical mirror 1 is connected to a guiding frame 5.
  • Three springs 6 applying force in the plane of the elastic element 4 can be applied to create a negative spring stiffness in order to compensate stiffness of the position actuators 2 and the elastic element 4 itself.
  • the positioning rod 7 is directly connected to the optical mirror 1.
  • FIG 5 we see a schematic overview of a possible application of the position actuator according to the invention.
  • An arbitrary number of mirror segments 1 which together define a large mirror telescope, each with three position actuators 2 (only two depicted in this figure) per segment is shown.
  • the position difference between each segment, measured by edge sensors 3 as well as integrated accelerometers 7 attached to the mirror segment will be used as an input for the controller.
  • the gas supply consists out of a completely closed system where dry air or nitrogen is used in order to prevent possible freezing and corrosion problems by usage of the positioning system under freezing circumstances.
  • the low pressure supply lines are connected to the low pressure reservoir 4, from which the pump 5 pumps the gas to a higher pressure in reservoir 6 which is connected to the high pressure supply lines of the position actuators.
  • FIG 6 a block diagram of the control system is depicted.
  • the control system is based on two loops.
  • the inner loop is a fast acceleration loop, within the kHz or higher region, and the outer loop is a slow position loop.
  • the fast, inner loop consists of the acceleration sensor 2, delivering acceleration information of the load 1. This is used by the acceleration controller 12 to compute output for the voice coil electronics 9, driving the voice coil in the actuator 3. By means of this loop the acceleration of the load can be prescribed.
  • the outer loop controls the position of the load and uses the inner loop.
  • the outer loop consists of the position sensor 10 and the position controller 11.
  • the output of the position controller 11 is an input for the acceleration controller of the fast inner loop.
  • the output of the acceleration controller 12 is the input for the pneumatic controller 13 which attempts to minimize the voice coil actuation by driving the valve electronics 5 to increase or decrease the amount of gas in the actuator 3 by means of two valves 4.
  • the valves are connected to a high pressure buffer 6 on one side and a low pressure buffer 8 on the other side.
  • the circuit is closed by a pump

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Sustainable Development (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Astronomy & Astrophysics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Actuator (AREA)
  • Vibration Prevention Devices (AREA)
  • Magnetic Bearings And Hydrostatic Bearings (AREA)

Abstract

The invention concerns a long stroke position actuator with high load capacity and nanometer resolution, based on a combined electromagnetic and pneumatic actuator where the pneumatic actuator (1, 2, 3) handles the high force and low frequency part and the electromagnetic actuator (5, 7) handles the low force but high frequency part of the disturbance forces, in such a way that the pneumatic actuator output can be transferred to the load via a soft support, while the high frequent control can be done in the most direct and stiff way, by actuating directly on the load. Both actuators are combined in such a way that the resulting stiffness in force direction is equivalent to the sum of the stiffnesses of both actuators. Only frictionless guidings are implemented in order to obtain hysteresis free operation for highest accuracy and to prevent wear and maintenance.

Description

Long stroke position actuator with high load capacity and nanometer resolution
The invention of a long stroke position actuator with high load capacity and nanometer resolution is based on a combined electromagnetic and pneumatic actuator where the pneumatic actuator takes care of the high force and low frequency part and the electromagnetic actuator takes care of the low force but high frequency part of the disturbance forces. Both actuators are combined in such a way that the resulting stiffness in force direction is equivalent to the sum of the stiffnesses of both actuators.
Possible applications for this kind of actuators can be found in the world of astronomy where large mirror segments, which are exposed to gravity and environmental effects like temperature and wind fluctuation, have to be positioned with nanometer accuracy. An actuator in a closed loop control system opens possibilities for correction of position errors caused by disturbance forces.
Regarding the potentially large number of actuators required for large telescopes, a solution with high reliability and long lifetime expectations against reasonable costs will be required.
Nowadays there are several possible solutions which pretend to position large masses with high accuracy over long strokes. Conventional spindle driven actuators unfortunately don't have the required nanometer resolution as well as oil driven cylinders which are also contaminating the environment, friction wheel drives are missing the required force and linear motors or large voice coil actuators can not apply the force without high power dissipation. A combination of actuators like a combination of pneumatic and electromagnetic actuators, where the pneumatic actuator takes care of the high force and the electromagnetic actuator of the low force but high accuracy part, is also known. This combination can lead to high load performance but in order to maintain reliability and high accuracy, care should be taken in order to avoid contamination and internal friction in the actuator.
The invention concerns a position actuator able to avoid contamination and internal friction leading to high reliability and to optimize the overall positioning performance by applying adequate control strategies. Especially the use of this position actuator in a positioning and guiding system for large segmented mirror telescopes will be shown. Also a possibility to avoid the complex and heavy whiff 1 etre e s , mostly used in telescopes to support the mirrors, will be presented.
According to the inventor the above stated objectives can be fulfilled by operation of the pneumatic actuator with low stiffness for low frequency high load positioning demands and the magnetic actuator with high stiffness for high frequency positioning demands in a parallel way. In order to reach high positioning resolution, only elements without friction are used. The application of a completely closed gas supply and exhaust system is used in order to obtain high reliability by avoiding internal contamination. Fig.l is a schematic drawing of the system according to the invention, Fig.2 is a schematic drawing of the system according to the invention specially adapted for positioning large optical mirrors, Fig.3 is a schematic drawing of a system with a three actuator support of a large optical mirror, where the position actuator and guiding are integrated, Fig.4 is a schematic top view of figure 3, Fig.5 is a schematic drawing of an application in a multi segment mirror telescope with gas supply layout. Fig.6 is a block diagram of a positioning system according to the present invention.
In figure 1 the positioning system according to the invention is depicted. The pneumatic actuator chamber 15, comprises a bellows defined by the elastic element 2, a side/bottom wall 1 and moveable lid 3 which is airtight connected to the actuator rod 4. One gas supply line with a pressure higher than required in the inner chamber is connected via the input 13 to a buffer chamber 12 and by means of a valve 14 to the chamber 15, while an other gas supply with a pressure lower than required in the inner chamber is connected via the output 9 to a buffer chamber 10 and by means of a valve 8 to the chamber 15. Controlling the flow through each valve makes it possible to control the amount of gas in the chamber 15 and therefore also the position and or applicable force of output rod 4.
The magnetic actuator comprising the magnet 5 and coil 7 is positioned in such a way that the resulting stiffness of the position actuator is the sum of the pneumatic and the magnetic actuator. The magnetic actuator is used in order to make position corrections with relative low force but high bandwidth superimposed on the position of the pneumatic actuator, which requires a magnetic actuator with a stroke larger than the stroke of the pneumatic actuator. To obtain maximal stiffness in the accurate positioning loop the magnetic actuator is directly connecting the frame 11 with the positioning rod 4. In order to obtain friction less guiding of the coil 7 in the magnet 5, an elastic guiding 6 is foreseen.
Placing the magnetic actuator inside the pneumatic chamber will shield the magnetic actuator from environmental influences and will increase reliability and performance. The use of a completely sealed bellows will avoid internal friction and also makes the position actuator vacuum c omp atibl e .
In figure 2 special adaptations have been made to optimize the position actuator for positioning and supporting large optical mirrors. In order to optimize position control of an optical mirror it is worthwhile to make a distinction between low and high frequency position control. The low frequency position control will be controlled by the pneumatic system and can be combined with soft support of the optical mirror, while the high frequent control can be done in the most direct way by actuating directly on the optical mirror. For this reason the optical mirror 1 is supported by a passive or active deformable medium 2 which is connected to the support 3. This support 3 is air-tight sealed by means of a membrane 17 attached to the positioning rod 18. In this way the support 3 will be properly aligned with respect to the optical mirror 1. The pneumatic actuator chamber 16, comprises a bellows defined by the elastic element 4, a side/bottom wall 5 and moveable support 3 which supports the optical mirror 1. One gas supply line with a pressure higher than required in the inner chamber is connected via the input 14 to a buffer chamber 13 and by means of a valve 15 to the chamber 16, while an other gas supply with a pressure lower than required in the inner chamber is connected via the output 10 to a buffer chamber 11 and by means of a valve 9 to the chamber 16. Controlling the flow through each valve makes it possible to control the amount of gas in the chamber 16 and therefore also the position and or applicable force on the optical mirror 1. The magnetic actuator comprising magnet 6 and coil 8 is positioned in such a way that the resulting stiffness of the position actuator is the sum of the pneumatic and the magnetic actuator. The magnetic actuator is used to make position corrections with relative low force but high bandwidth superimposed on the position of the pneumatic actuator, which requires a magnetic actuator with a stroke larger than the stroke of the pneumatic actuator. To obtain maximal stiffness in the accurate positioning loop the magnetic actuator is directly connecting the frame 12 with the optical mirror 1. In order to obtain friction less guiding of the coil 8 in the magnet 6, an elastic guiding 7 is foreseen.
Placing the magnetic actuator inside the pneumatic chamber will shield the magnetic actuator from environmental influences and will increase reliability and performance. The use of a completely sealed bellows will avoid internal f r i c t i o n .
In figure 3, and figure 4 a system with a three actuator support of a large optical mirror is schematically shown. An optical mirror 1 is supported by three position actuators 2 as described in figure 2. In this way the optical mirror will be supported on a large surface by an elastic medium 3 which is self aligning with respect to the optical mirror. In order to guide the optical mirror in lateral directions, an elastic element 4, like three folded leaf springs, attached with interface 9 to the optical mirror 1 is connected to a guiding frame 5. In this way we have connected the optical mirror in six degrees of freedom with respect to the frame 5 from which the three required degrees of freedom can be positioned by the actuators. Three springs 6 applying force in the plane of the elastic element 4 can be applied to create a negative spring stiffness in order to compensate stiffness of the position actuators 2 and the elastic element 4 itself. In order to obtain maximal performance with respect to accuracy the positioning rod 7 is directly connected to the optical mirror 1.
In figure 5 we see a schematic overview of a possible application of the position actuator according to the invention. An arbitrary number of mirror segments 1 , which together define a large mirror telescope, each with three position actuators 2 (only two depicted in this figure) per segment is shown. The position difference between each segment, measured by edge sensors 3 as well as integrated accelerometers 7 attached to the mirror segment will be used as an input for the controller. The gas supply consists out of a completely closed system where dry air or nitrogen is used in order to prevent possible freezing and corrosion problems by usage of the positioning system under freezing circumstances. The low pressure supply lines are connected to the low pressure reservoir 4, from which the pump 5 pumps the gas to a higher pressure in reservoir 6 which is connected to the high pressure supply lines of the position actuators.
In figure 6 a block diagram of the control system is depicted. The control system is based on two loops. The inner loop is a fast acceleration loop, within the kHz or higher region, and the outer loop is a slow position loop. The fast, inner loop consists of the acceleration sensor 2, delivering acceleration information of the load 1. This is used by the acceleration controller 12 to compute output for the voice coil electronics 9, driving the voice coil in the actuator 3. By means of this loop the acceleration of the load can be prescribed. The outer loop controls the position of the load and uses the inner loop. The outer loop consists of the position sensor 10 and the position controller 11. The output of the position controller 11 is an input for the acceleration controller of the fast inner loop. The output of the acceleration controller 12 is the input for the pneumatic controller 13 which attempts to minimize the voice coil actuation by driving the valve electronics 5 to increase or decrease the amount of gas in the actuator 3 by means of two valves 4. The valves are connected to a high pressure buffer 6 on one side and a low pressure buffer 8 on the other side. The circuit is closed by a pump

Claims

1. An actuator system for positioning a large load over strokes of tens of millimeters with nanometer resolution comprising a pneumatic actuator and a magnetic actuator placed in such a way that the magnetic actuator is completely sealed from the environment and that the total stiffness in the positioning direction is determined by the sum of the stiffnesses of the pneumatic and magnetic actuator each.
2. The actuator system according to the former claim, wherein the pneumatic actuator handles the low frequency, high force positioning demands and the magnetic actuator handles the high frequency, low force but nanometer accurate positioning demands
3. The actuator system according to one or more of the former claims, wherein the system comprises: a magnetic actuator in line and directly connecting the frame with the actuator rod to the load and; an elastic guiding of the magnet with respect to the coil; a pneumatic force acting on the same actuator rod, completely gas tight and flexible sealed in the chamber with a bellows fixating only one degree of freedom and; an elastic pivot in the actuator rod allowing a load connection only determining the positioning direction; flow control valves between internal buffers and the pneumatic chamber.
4. The actuator system according to one or more of the former claims, wherein the pneumatic actuator output can be transferred to the load via a soft support, while the high frequency control can be done in the most direct and stiff way by actuating directly on the load comprising; a magnetic actuator in line and directly connecting the frame with the actuator rod to the load and; an elastic guiding of the magnet with respect to the coil; a pneumatic force acting on a separate plateau completely gas tight and flexible sealed in the chamber with a bellows fixating only one degree of freedom and therefore able to align itself with respect to the load; a passive or active deformable medium between the plateau and the load; an elastic pivot in the actuator rod allowing a load connection only determining the positioning direction; flow control valves between internal buffers and the pneumatic chamber.
5. The actuator system according to one or more of the former claims, wherein the air volume inside and or with a connected buffer can be tuned for optimal spring s tif f ne s s .
6. The actuator system according to one or more of the former claims, wherein a second pneumatic actuator according to one of the former claims is integrated in such a way that a force can be applied in the opposite direction of the first pneumatic actuator.
7. The actuator system according to one or more of the former claims with the characteristic that all of the parts which are in contact with the environment are vacuum compatible.
8. The actuator system according to one or more of the former claims with the characteristic that the pneumatic actuator, the high pressure gas supply and the low pressure gas supply are part of a completely closed pneumatic system.
9. The actuator system according to one or more of the former claims, where air, dry nitrogen or another gas is used as a medium to operate the pneumatic actuator.
10. The actuator system according to one or more of the former claims with the characteristic that the pneumatic valves are integrated in the actuator system and don't have to close completely so they can be designed in such a way that no mechanical contact and friction occurs during operation of these valves.
11. The actuator system according to one or more of the former claims where the low frequency positioning demands can be controlled by a low bandwidth positioning sensor and the pneumatic actuator and a high bandwidth acceleration signal from the, to be positioned, load will be used in combination with the magnetic actuator in order to obtain high end positioning accuracy demands, where; the control system is based on two loops, a fast acceleration loop, within the kHz or higher region, and a slow position loop where; the fast acceleration loop consists of an acceleration sensor, delivering acceleration information of the load, used by an acceleration controller to compute output for the voice coil electronics, driving the voice coil in the actuator and; the positioning loop consisting of a position sensor and a position controller, serving as an input for the acceleration controller of the fast acceleration loop, where; the output of the acceleration controller is the input for the pneumatic controller attempting to minimize the voice coil actuation by driving the valve electronics to increase or decrease the amount of gas in the pneumatic actuator by means of at least one valve.
12. A load positioning system for positioning an optical mirror comprising: three actuator systems according to one or more of the former claims and; an elastic element realizing lateral guiding of the optical mirror in such a way that all movements are guided without friction and; a negative spring stiffness is foreseen in order to compensate guiding stiffnesses
13. A system with the characteristic that minimal two loads have to be positioned, each supported by minimal one actuator according to one or more of the former claims.
14. A system according to claims 12 or 13 with the characteristic that the loads are mirror segments of a segmented mirror telescope.
PCT/NL2005/000437 2004-06-28 2005-06-15 Long stroke position actuator with high load capacity and manometer resolution WO2006001691A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1026509 2004-06-28
NL1026509A NL1026509C2 (en) 2004-06-28 2004-06-28 A long-stroke actuator with a high bearing capacity and nanometer resolution which can also be used as a vibration isolator.

Publications (1)

Publication Number Publication Date
WO2006001691A1 true WO2006001691A1 (en) 2006-01-05

Family

ID=34955629

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL2005/000437 WO2006001691A1 (en) 2004-06-28 2005-06-15 Long stroke position actuator with high load capacity and manometer resolution

Country Status (2)

Country Link
NL (1) NL1026509C2 (en)
WO (1) WO2006001691A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100495103C (en) * 2006-07-21 2009-06-03 中国科学院上海光学精密机械研究所 Locking mechanism of sampling reflector driving platform
CN104808309A (en) * 2015-04-15 2015-07-29 中国科学院国家天文台南京天文光学技术研究所 Electromechanical permanent magnet type force actuator for actively supporting astronomical telescope plane
EP3121639A4 (en) * 2014-03-19 2017-11-22 Boe Technology Group Co. Ltd. Three-dimensional display system
US9976045B2 (en) 2013-11-07 2018-05-22 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds
CN110133820A (en) * 2019-05-17 2019-08-16 中国科学院国家天文台南京天文光学技术研究所 The nanoscale precise displacement actuator of large-scale segmented mirror optical telescope
US10526503B2 (en) 2013-11-07 2020-01-07 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds and non-fluorinated polymer
JP7509604B2 (en) 2020-08-21 2024-07-02 株式会社アサヒエンタープライズ Actuator

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3427097A (en) * 1965-08-24 1969-02-11 Dryden Hugh L Pneumatic mirror support system
US4484798A (en) * 1981-05-01 1984-11-27 U.S. Philips Corporation Method of manufacturing a multiple mirror reflector for a land based telescope
US4950063A (en) * 1989-02-28 1990-08-21 The United States Of America As Represented By The Secretary Of The Air Force Automatic compensation of optical path for gimbaled phased array telescope
WO1993001577A1 (en) * 1991-07-12 1993-01-21 Denne Developments Limited Motion imparting apparatus
DE4326561A1 (en) * 1993-08-07 1995-02-09 Zeiss Carl Fa Method for supporting a mirror, and a mirror support
DE19727344A1 (en) * 1996-07-12 1998-02-05 Smc Corp Linear actuator
US6138458A (en) * 1998-12-02 2000-10-31 Griffin; William S. Electro-pneumatic actuator and servo-valve for use therewith
US6268667B1 (en) * 1998-02-20 2001-07-31 Advanced Motion Technologies, Llc Apparatus for producing linear motion
US20030155194A1 (en) * 2002-02-20 2003-08-21 Kienholz David A. Hybrid pneumatic-magnetic isolator-actuator
DE10244260A1 (en) * 2002-09-24 2004-04-01 Festo Ag & Co. Linear drive device

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3427097A (en) * 1965-08-24 1969-02-11 Dryden Hugh L Pneumatic mirror support system
US4484798A (en) * 1981-05-01 1984-11-27 U.S. Philips Corporation Method of manufacturing a multiple mirror reflector for a land based telescope
US4950063A (en) * 1989-02-28 1990-08-21 The United States Of America As Represented By The Secretary Of The Air Force Automatic compensation of optical path for gimbaled phased array telescope
WO1993001577A1 (en) * 1991-07-12 1993-01-21 Denne Developments Limited Motion imparting apparatus
DE4326561A1 (en) * 1993-08-07 1995-02-09 Zeiss Carl Fa Method for supporting a mirror, and a mirror support
DE19727344A1 (en) * 1996-07-12 1998-02-05 Smc Corp Linear actuator
US6268667B1 (en) * 1998-02-20 2001-07-31 Advanced Motion Technologies, Llc Apparatus for producing linear motion
US6138458A (en) * 1998-12-02 2000-10-31 Griffin; William S. Electro-pneumatic actuator and servo-valve for use therewith
US20030155194A1 (en) * 2002-02-20 2003-08-21 Kienholz David A. Hybrid pneumatic-magnetic isolator-actuator
DE10244260A1 (en) * 2002-09-24 2004-04-01 Festo Ag & Co. Linear drive device

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100495103C (en) * 2006-07-21 2009-06-03 中国科学院上海光学精密机械研究所 Locking mechanism of sampling reflector driving platform
US9976045B2 (en) 2013-11-07 2018-05-22 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds
US10208223B2 (en) 2013-11-07 2019-02-19 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds
US10526503B2 (en) 2013-11-07 2020-01-07 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds and non-fluorinated polymer
US11292934B2 (en) 2013-11-07 2022-04-05 3M Innovative Properties Company Fluoropolymer coatings comprising aziridine compounds and non-fluorinated polymer
EP3121639A4 (en) * 2014-03-19 2017-11-22 Boe Technology Group Co. Ltd. Three-dimensional display system
CN104808309A (en) * 2015-04-15 2015-07-29 中国科学院国家天文台南京天文光学技术研究所 Electromechanical permanent magnet type force actuator for actively supporting astronomical telescope plane
CN110133820A (en) * 2019-05-17 2019-08-16 中国科学院国家天文台南京天文光学技术研究所 The nanoscale precise displacement actuator of large-scale segmented mirror optical telescope
JP7509604B2 (en) 2020-08-21 2024-07-02 株式会社アサヒエンタープライズ Actuator

Also Published As

Publication number Publication date
NL1026509C2 (en) 2005-12-30

Similar Documents

Publication Publication Date Title
EP1744215B1 (en) Supporting device for supporting vibration sensitive components
EP0647788B1 (en) Tare supporting apparatus
WO2006001691A1 (en) Long stroke position actuator with high load capacity and manometer resolution
CN108962336B (en) Two-dimensional parallel flexible micro-motion platform based on piezoelectric drive
US9429208B2 (en) Vibration isolator with zero stiffness whose angle degree of freedom is decoupled with spherical air bearing
US5467720A (en) Support device
US9423000B2 (en) Magnetically suspended vibration isolator with zero stiffness whose angle degree of freedom is decoupled with a joint ball bearing
US6570298B2 (en) Vibration control device and driving method thereof
JPH06183561A (en) Moving stage device
KR100526855B1 (en) Grinder pressing device
WO2014094687A2 (en) Magnetically suspended and plane-drove vibration isolator with zero stiffness whose angle degree of freedom is decoupled with a spherical air bearing
US20230094685A1 (en) Stage apparatus, exposure apparatus, method of manufacturing flat panel display, and device manufacturing method
CN110941181A (en) Rigid-flexible coupling motion platform control method for piezoelectric ceramic connection
CN209919324U (en) Rigid-flexible coupling platform with cylinder type rigidity switching device and motion platform
US20050140961A1 (en) Anti-vibration system, method of controlling the same, exposure apparatus, and device manufacturing method
KR20180049671A (en) Piezoelectric direct drive valve system
JP3135404B2 (en) Stage device and system using it
JP2001241439A (en) Moving device provided with hydrostatic bearing
KR102214590B1 (en) Control system for controlling fluid actuators
CN113212801B (en) Positive stress electromagnetic two-dimensional deflection adjusting device and method with embedded strain sensing
CN103062317A (en) Vibration isolator with characteristics of two-dimensional flexible hinge angle decoupling and magnetic levitation plane drive positioning
JP3963805B2 (en) Fine movement device
JP4198853B2 (en) Hybrid actuator
KR100738952B1 (en) Motion-imparting apparatus
CN218846085U (en) Air pressure balance system for closed cavity of stage lamp and waterproof stage lamp with air pressure balance system

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Country of ref document: DE

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase