Active valve control is investigated for force tracking of fluidic flexible matrix composite (F2MC) variable stiffness structures through analytical and experimental studies. F2MC structures are based upon fluid-filled flexible matrix composite tubes, and previous investigations have shown that several orders of magnitude change in stiffness can theoretically be achieved by opening and closing the inlet valve to the tubes. In this article, a simple analytical model of the F2MC system is developed that captures the dynamics of the composite tube, the servovalve, and the flow of the fluid through the valve. A combined observer/ regulator control system is determined using linearized equations of motion and is applied to the non-linear system. Analysis and experimental results demonstrate that the F2MC system can track a desired force—displacement curve using active valve control.
Alleyne, A. and Hedrick, J.K.1995. ‘‘Nonlinear Adaptive Control of Active Suspensions ,’’ IEEE Transactions on Control Systems Technology , 3:94-101.
2.
Alleyne, A. and Liu, R.2000. ‘‘A Simplified Approach to Force Control for Electro-Hydraulic Systems,’’ Control Engineering Practice, 8:1347-1356.
3.
Alleyne, A., Neuhaus, P.D. and Hedrick, J.K.1993. ‘‘Application of Nonlinear Control Theory to Electronically Controlled Suspensions,’’ Vehicle System Dynamics, 22:309-320.
4.
Blackburn, J., Reethof, G. and Shearer, J.L.1960. Fluid Power Control, The Technology Press, John Wiley & Sons, New York, NY.
5.
Hwang, C.1996. ‘‘Sliding Mode Control Using Time-Varying Switching Gain and Boundary Layer for Electrohydraulic Position and Differential Pressure Control,’’ IEE Proceedings-Control Theory and Applications, 143:325-332.
6.
Hyer, M.W. and White, S.R.1998. Stress Analysis of Fiber-Reinforced Composite Materials , WCB McGraw-Hill, Boston, MA.
7.
Kim, D. and Tsao, T.2000. ‘‘A Linearized Electrohydraulic Servovalve Model for Valve Dynamics Sensitivity Analysis and Control System Design, ’’ Journal of Dynamic Systems, Measurement, and Control, 122:179-187.
8.
Lewis, F. and Syrmos, V.1995. Optimal Control, Wiley-Interscience , New York, NY.
9.
Lin, S. and Akers, A.1991. ‘‘Dynamic Analysis of a Flapper-Nozzle Valve,’’ Journal of Dynamic Systems, Measurement, and Control, 113:163-185.
10.
Lotfi-Gaskarimahalle, A. and Rahn, C.D.2009. ‘‘Switched Stiffness Vibration Controllers for Fluidic Flexible Matrix Composites’’, In: Proceedings of Design Engineering Technical Conference, San Diego, CA, DETC2009-87591.
11.
Martin, D. and Burrows, C. 1976. ‘‘The Dynamic Characteristics of an Electro-Hydraulic Servovalve , (American Society of Mechanical Engineers, 1976),’’ ASME, Transactions, Series G- Journal of Dynamic Systems, Measurement, and Control, 98:395-406.
12.
McCloy, D. and Martin, H.1973. The Control of Fluid Power, Halsted Press, New York, NY.
13.
Meirovitch, L.1997. Principles and Techniques of Vibrations, Prentice Hall, Upper Saddle River, New Jersey, NJ.
14.
Merritt, H.E.1967. Hydraulic Control Systems, John Wiley & Sons Inc, New York, NY.
15.
Nickel, V., Perry, J. and Garret, A.L.1963. ‘‘Development of Useful Function in the Severely Paralyzed Hand,’’ The Journal of Bone and Joint Surgery, 45:933-952.
16.
Philen, M., Phillips, D. and Baur, J.2009. ‘‘Variable Modulus Materials Based Upon F2MC Reinforced Shape Memory Polymers’’, In: 17th AIAA/ASME/AHS Adaptive Structures Conference, 4-7 May, AIAA, Palm Springs, CA.
17.
Philen, M., Shan, Y., Bakis, C.E., Wang, K.W. and Rahn, C.D.2006. ‘‘Variable Stiffness Adaptive structures Utilizing Hydraulically Pressurized Flexible Matrix Composites With Valve Control’’ , In: 47th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, 1-4 May, American Institute of Aeronautics and Astronautics Inc., Newport, RI, United States.
18.
Philen, M.K., Shan, Y., Prakash, P., Wang, K.W., Rahn, C.D., Zydney, A.L. and Bakis, C.E.2007a. ‘‘Fibrillar Network Adaptive Structure With Ion-Transport Actuation,’’ Journal of Intelligent Material Systems and Structures, 18:323-334.
19.
Philen, M., Shan, Y., Wang, K.W., Bakis, C.E. and Rahn, C.D.2007b. ‘‘Fluidic Flexible Matrix Composites for the Tailoring of Variable Stiffness Adaptive Structures’’, In: AIAA/ASME/ ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, 23-26 April, Honolulu, Hawaii, American Institute of Aeronautics and Astronautics Inc. , Reston, VA, United States.
20.
Plummer, A. and Vaughan, N.1996. ‘‘Robust Adaptive Control for Hydraulic Servosystems,’’ Journal of Dynamic Systems, Measurement, and Control, 118:237-244.
21.
Shan, Y., Lotfi, A., Philen, M., Li, S., Bakis, C.E., Rahn, C.D. and Wang, K.W.2007. ‘‘Fluidic Flexible Matrix Composites for Autonomous Structural Tailoring’’, In: Proceedings of SPIE - The International Society for Optical Engineering, Society of Photo-Optical Instrumentation Engineers, SPIE Conference on Smart Structures and Materials , San Diego, CA.
22.
Shan, Y., Philen, M.P., Bakis, C.E., Wang, K.W. and Rahn, C.D.2006. ‘‘Nonlinear-Elastic Finite Axisymmetric Deformation of Flexible Matrix Composite Membranes Under Internal Pressure and Axial Force ,’’ Composites Science and Technology, 66:3053-3063.
23.
Shan, Y., Philen, M., Li, S., Bakis, C.E., Rahn, C.D. and Wang, K.W.2008. ‘‘Variable Stiffness Structures Utilizing Fluidic Flexible Matrix Composites,’’ Journal of Intelligent Material Systems and Structures, 20:443-456.
