Publications : Conference Archives

1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1989 | 1988 | 1987 | 1986 | 1985 | 1984

1999

  1. Chopra, I., “Status of Application of Smart Structures Technology to Rotorcraft Systems,” International Conference on Adaptive Structures, Cambridge, MA, October 1998.
  2. Bernhard, A. P. and Chopra, I., “Analytical Model of a Rotor with Active Blade Tips,” SPIE’s 6th International Symposium on Smart Structures and Materials, Newport Beach, Calif., March 1999.
  3. Lee, T. and Chopra, I., “Development and Validation of a Refined Piezostack-Actuated Trailing-Edge Flap Actuator for Helicopter Rotor,” SPIE’s 6th International Symposium on Smart Structures and Materials, Newport Beach, Calif., March 1999.
  4. Shaner, M. C. and Chopra, I., “Design and Testing of a Leading-Edge Flap Actuator,” SPIE’s 6th International Symposium on Smart Structures and Materials, Newport Beach, Calif., March 1999.
  5. Sirohi, J. and Chopra, I., “Fundamental Understanding of Piezoelectric Strain Sensors,” SPIE’s 6th International Symposium on Smart Structures and Materials, Newport Beach, Calif., March 1999.
  6. Prahlad, H. and Chopra, I., “Experimental Characterization of Ni-Ti Shape Memory Alloy Wires under Complex Loading Conditions,” SPIE’s 6th International Symposium on Smart Structures and Materials, Newport Beach, Calif., March 1999.
  7. Yeo, H. and Chopra, I., “Coupled Rotor/Fuselage Vibration Analysis Using Detailed 3-D Airframe Model,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  8. Koratkar, N. and Chopra, I., “Development of a Mach Scaled Rotor Model with Piezoelectric Bender Actuated Trailing-Edge Flaps,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  9. Lee, T. and Chopra, I., “Design and Spin Testing of an Active Trailing Edge Flap Actuated with Piezostacks,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  10. Epps, J. and Chopra, I., “In-Flight Tracking of Helicopter Rotor Blades Using Shape Memory Alloy Actuators,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  11. Spencer, M., Sanner, R. and Chopra, I., “A Neural Network Controller for Rotor Blades with Trailing Edge Flaps,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  12. Jung, S. N., Nagaraj, V. T. and Chopra, I., “A Refined Structural Dynamics Model for Composite Rotor Blades,” 40th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, St. Louis, MO, April 1999.
  13. Koratkar, N. and Chopra, I., “Development of a Mach-Scaled Model with Piezoelectric Bender Actuated Trailing-Edge Flaps for Helicopter Individual Blade Control (IBC),” 55th Annual Forum of the American Helicopter Society, Montreal, Canada, May 1999.
  14. Bernhard, A. B. F. and Chopra, I., “Hover Testing of a Mach-Scale Rotor with Active Blade Twists,” 55th Annual Forum of the American Helicopter Society, Montreal, Canada, May 1999.
  15. Tishchenko, M. N., Nagaraj, V. T. and Chopra, I., “Unmanned Transport Helicopters,” 55th Annual Forum of the American Helicopter Society, Montreal, Canada, May 1999.
  16. Yeo, H. and Chopra, I., “Fundamental Issues Related to the Prediction of Coupled Rotor/Airframe Vibrtion,” Proceedings of the 25th European Rotorcraft Forum, Rome, Italy, Sept. 1999.

1998

  1. Koratkar, N. A. and Chopra, I., “Design, Fabrication and Hover Testing of A Mach-Scaled Rotor Model with Piezobimorph Actuated Trailing-Edge Flaps,” 1998 North American Conference on Smart Structures and Materials, San Diego, Calif., March 1998.
  2. Lee, T. and Chopra, I., “Design and Testing of an Active Trailing-Edge Flap for a Rotor Using Piezostacks,” 1998 North American Conference on Smart Structures and Materials, San Diego, Calif., March 1998.
  3. Epps, J. J. and Chopra, I., “In-Flight Tracking of Helicopter Rotor Blades Using Shape Memory Alloys,” 1998 North American Conference on Smart Structures and Materials, San Diego, Calif., March 1998.
  4. Sirohi, J. and Chopra, I., “Investigations on Piezoceramic Actuator Response,” 1998 North American Conference on Smart Structures and Materials, San Diego, Calif., March 1998.
  5. Yeo, H. and Chopra, I., “Effect of Modeling Refinements on Coupled Rotor/Fuselage Vibration Analysis,” 54rth Annual Forum of the American Helicopter Society, Washington DC, May 1998.
  6. Spencer, M., Sanner, R. and Chopra, I., “Development of Neural Network Controller for Smart Structure Activated Rotor Blades,” 39th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Long Beach, CA, April 1998.
  7. Bernhard, A. P. F. and Chopra, I., “Hover Testing of an Active Rotor Blade Tip and Structural Analysis of the Actuator Beam,” 39th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Long Beach, CA, April 1998.
  8. Jung, S. N., Nagaraj, V. T. and Chopra, I., “Assessment of Composite Rotor Blade Modeling Techniques,” AHS International Meeting on Advanced Rotorcraft Technology and Disaster Relief, Gifu, Japan, April 1998.
  9. Jung, S. N., Nagaraj, V. T. and Chopra, I., “A General Structural Model for Thin- and Thick-Walled Composite Blades with Elastic Couplings,” Proceedings of the 24th European Rotorcraft Forum, Marseilles, France, Sept. 1998

1997

  1. Ganguli, R., Chopra, I. and Weller, W., “Validation of Calculated Vibratory Rotor Hub Loads with Experimental Data,” 53rd Annual Forum of the American Helicopter Society, Virginia Beach, VA, April 1997.
  2. Chopra, I., “Status of Application of Smart Structures Technology to Rotorcraft Systems,” Proceedings of Innovation in Rotorcraft Technology, Royal Aeronautical Society, London, June 1997.
  3. Yeo, H. and Chopra, I., “Coupled Rotor/Fuselage Vibration Analysis for a Teetering Rotor and Comparison with Flight Test Data,” Proceedings of the 23rd European Rotorcraft Forum, Dresden, Germany, Sept. 1997.
  4. Milgram, J. and Chopra, I., “Dynamics of an Actively Controlled Plain Trailing Edge Flap System for a Modern Bearingless Rotor”, Proceedings of the 23rd European Rotorcraft Forum, Dresden, Germany, Sept. 1997.
  5. Chen, P. and Chopra, I., “Wind Tunnel Test of a Smart Rotor Model with Individual Blade Twist Control” 1997 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1997.
  6. Koratkar, N. A. and Chopra, I., “Testing and Validation of a Froude Scaled Helicopter Rotor Model with Piezo-Bimorph Actuated Trailing-Edge Flaps” 1997 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1997.
  7. Spencer, M., Sanner, R. and Chopra, I.,”Adaptive Nonlinear Neural Network Controller for Rotorcraft Vibration,” 1997 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1997.
  8. Yeo, H. and Chopra, I., “Modeling Issues Related to Vibration Prediction of a Coupled Rotor/Fuselage System,” 38th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Kissimmee, FL, April 1997.
  9. Epps, J. J. and Chopra, I., “Compartive Evaluation of Shape Memory Alloy Constitutive Models with Test Data” 38th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Kissimmee, FL, April 1997.
  10. Chandra, R. and Chopra, I., “Actuation of Trailing Edge Flap in a Wing Model Using Piezostack Device,” 38th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Kissimmee, FL, April 1997.
  11. Hong, C. H. and Chopra, I., “Modeling and Validation of Induced Strain Actuation of Composite Coupled Plate,” 38th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Kissimmee, FL, April 1997.
  12. Bernhard, A. P. F. and Chopra, I., “Development of a Smart Moving-Blade-Tip and an Active-Twist Rotor Blade Driven by A Piezo-Induced Bending-Torsion Coupled Beam,” 53rd Annual Forum of the American Helicopter Society, Virginia Beach, VA, April 1997.

1996

  1. Ganguli, R., Chopra, I. and Haas, D. J., “Helicopter Rotor System Health Monitoring Using Numerical Simulation and Neural Networks,” 53rd Annual Forum of the American Helicopter Society, Virginia Beach, VA, April 1996.
  2. Chopra, I., “Overview on Smart Structure and Integrated Systems,” 1996 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1996.
  3. Bernhard, A. P. and Chopra, I., “Development of a Smart Rotor with a Tip Activated by a Bending-Torsion Coupled Composite Beam,” 1996 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1996.
  4. Spencer, B. and Chopra, I., “Design and Testing of Helicopter Trailing-Edge Flap with Piezoelectric Stack Actuators,” 1996 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1996.
  5. Tracy, A. and Chopra, I., “Aeromechanical Stability Analysis and Testing of a Composite Bearingless Rotor,” 37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Salt Lake City, Uttah, April 1996.
  6. Srinivas, V. and Chopra, I., “An Assessment of Aeroelastic Analyses for Tiltrotor Aircraft,”37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Salt Lake City, Uttah, April 1996.
  7. Ganguli, R., Chopra, I. and Haas, D., “Simulation and Detection of Rotor-System Faults,” 37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Salt Lake City, Uttah, April 1996.
  8. Bernhard, A. and Chopra, I., “Hover Testing of a Smart Flap Activated by Bending-Torsion Coupled Beam,” 37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Salt Lake City, Uttah, April 1996.
  9. Chen, P. and Chopra, I. “Wind Tunnel Testing of Smart Rotor with Induced-Strain Actuation of Blade Twist,” 37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, Salt Lake City, Uttah, April 1996.
  10. Srinivas, V. and Chopra, I., “Validation of a Comprehensive Aeroelastic for a Tiltrotor Aircraft,” 52nd Annual Forum of the American Helicopter Society, Washington D.C., June 1996.
  11. Milgram, J. and Chopra, I., “A Comprehensive Rotorcraft Aeroelastic Analysis with Trailing-Edge Flaps: Validation with Experimental Data, 52nd Annual Forum of the American Helicopter Society, Washington D.C., June 1996.
  12. Ganguli, R., Chopra, I. and Haas, D. J., “A Physics Based Model for Rotor System Health Monitoring,” Proceedings of the 22nd European Rotorcraft Forum and 13th European Helicopter Association Symposium, Brighton, UK, September 1996.
  13. Chopra, I., ” State-of-the-Art of Smart Structures and Integrated Systems” SPIE Far East & Pacific Rim Symposium on Smart Materials, Structures & MEMS, Bangalore, India, December 11-14, 1996

1995

  1. Ben-Zeev, O. and Chopra, I. “Development of an Improved Helicopter Rotor Model with Smart Trailing Edge Flaps for Vibration Suppression,” 1995 North American Conference on Smart Structures and Materials, San Diego, Calif., Feb. 1995.
  2. Milgram, J. and Chopra, I., “Helicopter Vibration Reduction with Trailing Edge Flaps,” 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, New Orleans, LA, April 1995.
  3. Ganguli, R., Chopra, I. and Haas, D., “Formulation of a Rotor Head Damage Detection Methodology,” 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, New Orleans, LA, April 1995.
  4. Srinivas, V., Chopra, I. and Nixon, M., “Assessment of Aeroelastic Analyses of Advanced Tiltoror Aircraft,” 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, New Orleans, LA, April 1995.
  5. Chen, P. and Chopra, I., “Hover Testing of a Smart Rotor with Induced-Strain Actuation of Blade Twist,” 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, New Orleans, LA, April 1995.
  6. Hu, C., Kawiecki, G., Chandra, R. and Chopra, I., “Bending-Torsional Response of Piezo-Actuated Thin-Walled Composite Beams,” 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Forum, New Orleans, LA, April 1995.
  7. Gandhi, F. and Chopra, I. “Analysis of Bearingless Main Rotor Dynamics with the Inclusion of an Improved Time Domain Nonlinear Elastomeric Damper Model,” 51st Annual Forum of the American Helicopter Society, Fort Worth, Texas, May 1995.
  8. Ganguli, R. and Chopra, I., “Aeroelastic Optimization of an Advanced Geometry Composite Helicopter Rotor,” 51st Annual Forum of the American Helicopter Society, Fort Worth, Texas, May 1995.
  9. Chen, P. and Chopra, I., “Individual Blade Control of a Smart Rotor with Induced Strain Actuation of Blade Twist,” American Helicopter Society Nation Technical Specialists’ Meeting on Rotorcraft Structures, Williamsburg, VA, Oct. 1995.
  10. Bernhard, A. P. F. and Chopra, I., “Development and Hover Testing of a Smart Trailing Edge Flap with a Piezo-Induced Bending-Torsion Coupled Actuator,” American Helicopter Society National Technical Specialists’ Meeting on Rotorcraft Structures, Williamsburg, VA, Oct. 1995.
  11. Ganguli, R., Chopra, I. and Haas, D, “Helicopter Rotor-System Damage Detection,” American Helicopter Society 2nd International Aeromechanics Specialists’ Conference, Bridgeport, CT, Oct. 1995.
  12. Milgram, J. and Chopra, I. “Active Control of Helicopter Vibratory Loads Using Trailing Edge Flaps,” American Helicopter Society 2nd International Aeromechanics Specialists’ Conference, Bridgeport, CT, Oct. 1995.

1994

  1. Bir, G. and Chopra, I., “Status of University of Maryland Advanced Rotorcraft Code (UMARC),” American Helicopter Society Aeromechanics Specialists Conference, San Francisco, California January 1994.
    Tracy, A. L., and Chopra, I., “Aeroelastic Analysis of a Composite Bearingless Rotor in Forward Flight with Improved Warping Modeling,” American Helicopter Society Aeromechanics Specialists Conference, San Francisco, California January 1994.
  2. Gandhi, F. and Chopra, I., “An Analytical Model for a Nonlinear Elastomeric Lag Damper and its Effect on Aeromechanical Stability in Hover,” American Helicopter Society Aeromechanics Specialists Conference, San Francisco, California January 1994.
  3. Chen, P. C. and Chopra, I., “Induced Strain Actuation of Composite Beams and Rotor Blades with Embedded Piezoceramic Elements,” 1994 North American Conference on Smart Structures and Materials, Orlando, Florida, Feb. 1994.
  4. Samak, D. K. and Chopra, I., “Design of High Force, High Displacement Actuators for Helicopter Rotors” 1994 North American Conference on Smart Structures and Materials, Orlando, Florida, Feb. 1994.
  5. Gandhi, F. and Chopra, I., “A Nonlinear Viscoelastic Damper Model: Constitutive Equation and Solution Scheme” 1994 North American Conference on Smart Structures and Materials, Orlando, Florida, Feb. 1994.
  6. Ganguli, R.. and Chopra, I., “Aeroelastic Optimization of a Helicopter Rotor to Reduce Vibration and Dynamic Stresses,” 35th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Hilton Head, SC, April 1994.
  7. Gandhi, F. and Chopra, I., “Elastomeric Lag Damper Effects on Flap-Lag Stability in Forward Flight” 35th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Hilton Head, SC, April 1994.
  8. Walz, C.. and Chopra, I., “Design and Testing of a Helicopter Rotor Model with Smart Trailing Edge Flaps,” 35th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Conference, Hilton Head, SC, April 1994.
  9. Bothwell, C. M., Chandra, R. and Chopra, I., “Torsional Actuation with Extension-Torsional Composite Coupling and Magnetostrictive Actuators,” 35th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Conference, Hilton Head, SC, April 1994.
  10. Park, C.. and Chopra, I., “Modeling Piezoceramic Actuation of Beams in Torsion,” 35th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference and Adaptive Structures Conference, Hilton Head, SC, April 1994.
  11. Milgram, J. and Chopra, I., “Helicopter Vibration Reduction with Dynamically Tuned Blade Pitch Links,” 50th Annual Forum of the American Helicopter Society, Washington DC, May 1994.
  12. Ganguli, R. and Chopra, 20th European Rotorcraft ForumI. “Aeroelastic Optimization of a Helicopter Rotor with Two-Cell Composite Blades,” , Amsterdam, Netherlands, October, 1994.

1993

  1. Park, C., Walz, C and Chopra, I., ” Bending and Torsion Models of Beams with Induced-Strain Actuators,” 1993 North American Conference on Smart Structures and Materials, Albuquerque, New Mexico, Feb. 1993.
  2. Samak, D. and Chopra, I., ” Feasibility Study to Build a Smart Rotor: Trailing Edge Flap Actuation,” 1993 North American Conference on Smart Structures and Materials, Albuquerque, New Mexico, Feb. 1993.
  3. Chen, P. C. and Chopra, I., “Feasibility Study to Build a Smart Rotor: Induced Strain Actuation,” 1993 North American Conference on Smart Structures and Materials, Albuquerque, New Mexico, Feb. 1993.
  4. Tracy, A. L. and Chopra, I., “Aeromechanical Stability of a Bearingless Composite Rotor in Forward Flight,” 34th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, La Jolla, California, April 1993.
  5. Bir, G. S. and Chopra, I., “Aeromechanical Stability of Rotorcraft with Advanced Geometry Blades,” 34th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, La Jolla, California, April 1993.
  6. Vellaichamy, S. and Chopra, I., “Effect of Modeling Techniques in the Coupled Rotor-Body Vibration Analysis,” 34th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, La Jolla, California, April 1993.
  7. Ganguli, R. and Chopra, I., “Aeroelastic Optimization of a Helicopter Rotor with Composite Tailoring,” 48th Annual Forum of the American Helicopter Society, St. Louis, Missouri, May 1993.
  8. Chopra, I., “Development of Smart Rotor,” 19th European Rotorcraft Forum, Cernobbio (Como), Italy, September, 1993.
  9. Srinivas, V., Chopra, I., Haas, D. and McCool, K., “Prediction of Yaw Control Effectiveness and Tail Rotor Loads,” Proceedings of the 19th European Rotorcraft Forum, Cernobbio (Como), Italy, September, 1993.

1992

  1. Smith, E. C. and Chopra, I., “Aeromechanical Stability of Helicopters with Composite Rotors in Forward Flight,” 48th Annual Forum of the American Helicopter Society, Washington D. C., June 1992.
  2. Smith, E. C. and Chopra, I., “Aeroelastic Response and Blade Loads of a Composite Rotor in Forward Flight,” 33rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Dallas, Texas, April 1992.
  3. Vellaichamy, S. and Chopra, I., “Aeroelastic Response of Helicopters with Flexible Fuselage Modeling,” 33rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Dallas, Texas, April 1992.
  4. Ganguli, R. and Chopra, I., “Aeroelastic Optimization of an Advanced Geometry Helicopter Rotor,” 33rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Dallas, Texas, April 1992.
  5. Wang, J. and Chopra, I., “Dynamics of Helicopters in Ground Resonance with and without Blade Dissimilarities,” 33rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Dallas, Texas, April 1992.
  6. Chandra, R. and Chopra, I., “Structural Modeling of Composite Beams with Induced Strain Actuation,” Recent Advances in the Structural Dynamic Modeling of Composite Rotor Blades and Thick Composites, American Society of Mechanical Engineers, AD- Vol. 30, Oct. 1992.

1991

  1. Chandra, R. and Chopra, I., “Coupled Composite Rotor Blades Under Bending and Torsional Loads,” Proceedings of the AHS Specialists’ Meeting on Rotorcraft Structures, Williamsburg, Virginia, Oct. 1991.
  2. Chopra, I., “Design and Analyis Trends of Helicopter Rotor Systems,” Proceedings of the Third South African Aeronautical Engineering Conference, Pretoria, South Africa, August 1991.
  3. Chandra, R. and Chopra, I., “Experimental and Theoretical Analysis of Composite I-Beams with Elastic Couplings,” 32nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Baltimore, Md, April 1991.
  4. Tracy, A. and Chopra, I., “Formulation and Evaluation of an Analytical Model for Composite Box-Beams Including Thermal Effects,” 32nd AIAA/ASME/ASCE/ AHS/ASC Structures, Structural Dynamics and Materials Conference, Baltimore, Md, April 1991.
  5. Vorwald, J. and Chopra, I., “Stability Pylon Whirl Flutter on Tilt-Rotor Aircraft,” 32nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Baltimore, Md, April 1991.
  6. Chan, W.Y. and Chopra, I., “Mechanics of Aeromechanical Stability of Hingeless Rotors,” International Specialists’ Meeting on Rotorcraft Basic Research, Georgia Institute of Technology, March 1991.
  7. Bir, G. S. and Chopra, I., “Effects of Nonlinear Elastomeric Dampers on Aeromechanical Stability of Helicopters,” International Specialists’ Meeting on Rotorcraft Basic Research, Georgia Institute of Technology, March 1991.
  8. Chandra, R. and Chopra, I., “Aanlytical-Experimental Investigation of Free-Vibration Charactertics of Rotating Composite I-Beams” 47th Annual Forum of the American Helicopter Society, Phoenix, Arizona.
  9. Wang, J. and Chopra, I., “Dynamics of Helicopters With Dissimilar Blades,” 47th Annual Forum of the American Helicopter Society, Phoenix, Arizona, May 1991.
  10. Chopra, I., and Samak, D. K., “Development of an Intelligent Rotor,” Proceedings of Conference on Active Materials and Adapative Structures, Arlington, Virginia, Oct., 1991.
  11. Chandra, R. and Chopra, I., “Structural Behavior of Two-Cell Composite Rotor Blades with Elastic Couplings,” 17th European Rotorcraft Forum, Berlin, Germany, Sept. 1991.

1990

  1. Wang, J. and Chopra, I., “Dynamics of Helicopters with Dissimilar Blades in Forward Flight,” 17th European Rotorcraft Forum, Berlin, Germany, September, 1990.
  2. Wang, J. and Chopra, I., “Bearingless Rotor Aeromechanical Stability Measurements and Correlations Using Nonlinear Aerodynamics,” 16th European Rotorcraft Forum, Glasgow, Scotland, September, 1990.
  3. Bir, G. S., Chopra, I., and Nguyen, K. Q., “Development of UMARC (University of Maryland Advanced Rotorcraft Code),” 46th Annual Forum of the American Helicopter Society, Washington, D.C., May 21-23, 1990.
  4. Torok, M. S. and Chopra, I., “Hingeless Rotor Blade Stability Using a Coupled Aeroelastic Analysis with Refined Aerodynamic Modeling,” 46th Annual Forum of the American Helicopter Society, Washington, D.C., May 21-23, 1990.
  5. Tasker, F. A. and Chopra, I., “Multi-output Implementation of a Modified Sparse Time Domain Technique for Rotor Stability Testing,” 31st AIAA/ASME/ ASCE/ASC/AHS Structures, Structural Dynamics and Materials Conference, Long Beach, California, April 1990.
  6. Lim, J. W. and Chopra, I., “Aeroelastic Optimization of a Helicopter Rotor Using Efficient Sensitivity Analysis,” 31st AIAA/ASME/ASCE/ASC/AHS Structures, Structural Dynamics and Materials Conference, Long Beach, California, April 1990.
  7. Smith, E. C. and Chopra, I., “Formulation and Evaluation of an Analytical Model for Composite Box-Beams,” 31st AIAA/ASME/ASCE/ASC/AHS Structures, Structural Dynamics and Materials Conference, Long Beach, California, April 1990.
  8. Kim, K. C. and Chopra, I., “Aeroelastic Analysis of Rotor Blades with Advanced Tip Shapes,” 31st AIAA/ASME/ASCE/ASC/AHS Structures, Structural Dynamics and Materials Conference, Long Beach, California, April 1990.
  9. Nguyen, K. Q. and Chopra, I., “Effects of Higher Harmonic Control Rotor Performance and Control Loads,” 31st AIAA/ASME/ASCE/ ASC/AHS Structures, Structural Dynamics and Materials Conference, Long Beach, California, April 1990.

1989

  1. Fledel, S., Rand, O. and Chopra, I., “Coupled Rotor/Airframe Vibration Analysis,” Fifteenth European Rotorcraft Forum, Amsterdam, Netherlands, Sept. 1989.
  2. Benquet, P. and Chopra, I., “Calculated Dynamic Response and Loads for an Advanced Tip Rotor in Forward Flight,” Fifteenth European Rotorcraft Forum, Amsterdam, Netherlands, Sept. 1989.
  3. Chandra, R. and Chopra, I., “Experimental-Theoretical Investigation of the Vibration Charactertics of Rotating Composite Box Beams,” AHS/Southwest Region-Sponsored National Specialists’ Meeting on Rotor Dynamics, Arlington, Texas, Nov. 1989.
  4. Wang, J., Chopra, I., Samak, D. J. and Green, M., “Theoretical and Experimental Investigation of Aeroelastic Stability of an Advanced Bearingless Rotor in Hover and Forward Flight,” AHS/Southwest Region-Sponsored National Specialists’ Meeting on Rotor Dynamics, Arlington, Texas, Nov. 1989.
  5. Chopra, I., “Perspectives in Aeromechanical Stability of Helicopters,” AHS/Southwest Region-Sponsored National Specialists’ Meeting on Rotor Dynamics, Arlington, Texas, Nov. 1989.
  6. Haas, D. and Chopra, I., “Aeroelastic Stability of Aircraft With Circulation Control Wings,” 30th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials Conference, Mobile, Alabama, April 1989.
  7. Nguyen, K. and Chopra, I., “Application of Higher Harmonic Control (HHC) to hingeless Rotor Systems,” 30th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials Conference, Mobile, Alabama, April 1989.
  8. Kim, K.C. and Chopra, I., “Effects of Three-Dimensional Aerodynamics on Blade Response and Loads,” 30th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials Conference, Mobile, Alabama. 1989.
  9. Tasker, F.A. and Chopra, I., “Nonlinear Damping Estimation from Rotor Stability Data Using Time and Frequency Domain Techniques,” 30th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials Conference, Mobile, Alabama, Apr. 1989.
  10. Nguyen, K. and Chopra, I., “Application of Higher Harmonic Control to Rotors Operating at High Speed,” 45th Annual Forum of the American Helicopter Society, Boston, Massachusetts, May 1989.
  11. Torok, M.S. and Chopra, I., “Rotor Loads Prediction Utilizing a Coupled Aeroelastic Analysis with Refined Aerodynamic Modeling,” 45th Annual Forum of the American Helicopter Society, Boston, Massachusetts, May 1989.

1988

  1. Chandra, R., Stemple, A. and Chopra, I., “Dynamic Behavior of Thin-Walled Composite Beams,” Proceedings of the National Specialists’ Meeting on Advanced Rotorcraft Structures, Williamsburg, Virginia, Oct. 1988.
  2. Wang, J., Jang, J. and Chopra, I., “Air Resonance of Hingeless Rotors in Forward Flight,” Fourteenth European Rotorcraft Forum, Milan, Italy, Sept. 1988.
    Torok, M.S. and Chopra, I., “A Coupled Rotor Aeroelastic Analysis Utilizing Non-Linear Aerodynamics and Refined Wake Modeling,” Fourteenth European Rotorcraft Forum, Milan, Italy, Sept. 1988.
  3. Elliott, A. S., Leishman, J.G. and Chopra, I., “A Nonlinear Unsteady Aerodynamic Model for Rotor Aeroelastic Analysis,” 44th Annual Forum of the American Helicopter Society, Washington, D.C., June 1988.
  4. Lim, J.W. and Chopra, I., “Stability Sensitivity Analysis for Aeroelastic Optimization of a Helicopter Rotor,” 29th AIAA Structures, Structural Dynamics and Materials Conference, Williamsburg, Virginia, April 1988.
  5. Jang, J. and Chopra, I., “Air Resonance of Bearingless Rotors in Forward Flight,” 2nd International Conference on Rotorcraft Basic Research, College Park, Maryland, Feb. 1988.
  6. Nguyen, K. and Chopra, I., “Actuation Power Requirement for Higher Harmonic Control Systems,” 2nd International Conference on Rotorcraft Basic Research, College Park, Maryland, Feb. 1988.
  7. Haas, D.J. and Chopra, I., “Flutter of Circulation Control Wings,” 29th AIAA Structures, Structural Dynamics and Materials Conference, Williamsburg, Virginia, Apr. 1988.
  8. Tasker, F.A. and Chopra, I., “Assessment of Transient Testing Techniques for Rotor Stability Measurement,” 29th AIAA Structures, Structural Dynamics and Materials Conference, Williamsburg, Virginia, Apr. 1988.
  9. Lim, J.W. and Chopra, I., “Aeroelastic Optimization of a Helicopter Rotor,” 44th Annual Forum of the American Helicopter Society, Washington, D.C., June 1988.

1987

  1. Kim, K.C., Desopper, A., and Chopra, I., “Dynamic Blade Response Calculations Using Improved Aerodynamic Modeling,” National Specialists’ Meeting on Aerodynamics and Aeroacoustics, American Helicopter Society, Arlington, Texas, Feb. 1987.
  2. Elliott, A. S. and Chopra, I., “Hingeless Rotor Response to Random Gust in Forward Flight,” AIAA Dynamics Specialist’ Meeting, Monterey, California, April 1987.
  3. Haas, D. and Chopra, I., “Aeroelastic Characteristics of Swept Circulation Control Wings,” AIAA Dynamics Specialists’ Meeting, Monterey, California, April 1987.
  4. Lim, J. and Chopra, I., “Aeroelastic Optimization of a Helicopter Blade in Forward flight,” Vol. 33, No. 4, Oct. 1988, AIAA Dynamics Specialists’ Meeting, Monterey, California, April 1987.
  5. Jang, J. and Chopra, I., “Air and Ground Resonance of an Advances Bearingless Rotor, AIAA Dynamics Specialists’ Meeting, Monterey, California, April 1987.
  6. Dull, A.L. and Chopra, I., “Aeroelastic Stability of Bearingless Rotors in Forward Flight,” 43rd Annual Forum of the American Helicopter Society, St. Louis, Missouri, May 1987.
  7. Raghavan, V., Pai, S.I. and Chopra, I., “Circulation Control Airfoils in Unsteady Flow,” 43rd Annual Forum of the American Helicopter Society, St. Louis, Missouri, May 1987.

1986

  1. Hong, C.H. and Chopra, I., “Flap-Lag-Torsion Stability of a Circulation Control Rotor Blade in Forward Flight,” Proceedings of the Circulation and Control Workshop, NASA Ames, NASA CP-2432, Feb. 1986.
  2. Kim, K.C., Bir, G.S. and Chopra, I., “Helicopter Response to an Airplane’s Vortex Wake,” 12th European Rotorcraft Forum, Garmisch, Germany, Sept. 1986.
  3. Chopra, I., “Aeroelastic Stability of a Bearingless Circulation Control Rotor in Forward Flight,” 12th European Rotorcraft Forum, Garmisch, Germany, Sept. 1986.

1985

  1. Hong, C.H. and Chopra, I., “Aeroelastic Stability Analysis of a Bearingless Composite Blade in Hover,” First International Conference on Rotorcraft Basic Research at Research Triangle Park, North Carolina, February, 1985.
  2. Panda, B. and Chopra, I., “Dynamic Stability of Hingeless and Bearingless Rotors in Forward Flight,” First International Conference on Rotorcraft Basic Research at Research Triangle Park, North Carolina, Feb. 1985.
  3. Bir, G.S. and Chopra, I., “Gust Response of Hingeless Rotors,” 41st Annual Forum of the American Helicopter Society, Fort Worth, Texas, May, 1985.
  4. Bir, G.S. and Chopra, I., “Prediction of Blade Stresses Due to Gust Loading,” 11th European Rotorcraft Forum, London, England, Sept. 1985.

1984

  1. Hong, C.H. and Chopra, I., “Aeroelastic Stability Analysis of a Composite Blade,” 40th Annual Forum of the American Helicopter Society, Crystal City, May 1984.
  2. Chopra, I., “Dynamic Stability of a Bearingless Circulation Control Rotor Blade in Hover,” Second Decennial AHS Specialists’ Meeting on Rotorcraft Dynamics at Ames Research Center, Moffett Field, California, November, 1984.
  3. Panda, B. and Chopra, I., “Flap-Lag-Torsion Stability in Forward Flight,” Second Decennial AHS Specialists’ Meeting on Rotorcraft Dynamics at Ames Research Center, Moffett Field, California, November, 1984.

1971-1983

  1. Chopra, I., “Aeroelastic Analysis of an Elastic Circulation-Controlled Rotor Blade in Hover” AIAA 24th SDM Conference, Lake Tahoe, Nevada, May, 1983.
  2. Sivaneri, N.S. and Chopra, I., “Finite Element Analysis for Bearingless Rotor Blade Aeroelasticity,” 38th Annual Forum of the American Helicopter Society, Anaheim, California, May, 1982.
  3. Chopra, I., “Dynamic Analysis of Constant-Lift and Free-Tip Rotors,” 22nd AIAA Dynamics Specialists’ Conference, Atlanta, Georgia, April 6-10, 1981.
  4. Chopra, I. and McCloud, J.L., “A Numerical Simulation of Open-Loop, Closed Loop and Adaptive Multicyclic Control Systems,” American Helicopter Society Northeast Region Symposium on the Helicopter Vibration – Technology for the Jet Smooth Ride, Hartford, Connecticut, November 2-4, 1981.
  5. Sivaneri, N.S. and Chopra, I., “Dynamic Stability of a Rotor Blade Using Finite Element Analysis,” 22nd AIAA Dynamics Specialists’ Conference, Atlanta, Georgia, April 6-10, 1981.
  6. Chopra, I. and Ballard, J., “Measurement of Control Stability Characteristics of a Wind Tunnel Model Using a Transfer Function Method,” AIAA 11th Aerodynamic Testing Conference, Colorado Springs, Colorado, March 18-20, 1980.
  7. Chopra, I. and Johnson, W., “Flap-Lag-Torsion Aeroelastic Stability of Circulation Controlled Rotors,” 34th Annual National Forum of the American Helicopter Society, Washington, D.C., May 1978.
  8. Chopra, I. and Dave, D.J., “Flutter Testing of a Typical Rocket Fin in High Speed Tunnel,” Proceedings of the Aeronautical Society of India, Silver Jubilee Technical Conference, Bangalore, April 1974.
  9. Chopra, I., and Sundararajan, D., “Design, Fabrication and Testing of Flutter Models of a Typical High Speed Fighter Wing,” Proceedings of the Aeronautical Society of India Technical Conference, held at Indian Institute of Technology, Kanpur, India, April 1971.