Reviews

• Z. Jane Wang, Insect Flight: From Newton's Law to Neurons , Annual Review of Condensed Matter Physics, 2016 [PDF]

Why do animals move the way they do? Bacteria, insects, birds, and fish share with us the necessity to move so as to live. Although each organism follows its own evolutionary course, it also obeys a set of common laws. At the very least, the movement of animals, like that of planets, is governed by Newton's law: All things fall. On Earth, most things fall in air or water, and their motions are thus subject to the laws of hydrodynamics. Through trial and error, animals have found ways to interact with fluid so they can float, drift, swim, sail, glide, soar, and fly. This elementary struggle to escape the fate of falling shapes the development of motors, sensors, and mind. Perhaps we can deduce parts of their neural computations by understanding what animals must do so as not to fall. Here I discuss recent developments along this line of inquiry in the case of insect flight. Asking how often a fly must sense its orientation in order to balance in air has shed new light on the role of motor neurons and steering muscles responsible for flight stability.



• Z. Jane Wang, Insect Flight , Princeton Companion to Applied Mathematics, 2015
• Z. Jane Wang, Dragonfly Flight , Physics Today October, 2008 [PDF]
• Z. Jane Wang, Insect Flight , McGraw Hill Year Book of Science and Technology, 2006
• Z. Jane Wang, Dissecting Insect Flight, Annual Review of Fluid Mechanics, 2005 [PDF]

Journals

• Z. Jane Wang, James Melfi Jr., Anthony Leonardo, Recovery Mechanisms in Dragonfly Righting Reflex, Science (2022). [Link]

Insects have evolved sophisticated reflexes to right themselves in mid-air. Their recovery mechanisms involve complex interactions among the physical senses, muscles, body, and wings, and they must obey the laws of flight. We sought to understand the key mechanisms involved in dragonfly righting reflexes and to develop physics-based models for understanding the control strategies of flight maneuvers. Using kinematic analyses, physical modeling, and three-dimensional flight simulations, we found that a dragonfly uses left-right wing pitch asymmetry to roll its body 180 degrees to recover from falling upside down in ~200 milliseconds. Experiments of dragonflies with blocked vision further revealed that this rolling maneuver is initiated by their ocelli and compound eyes. These results suggest a pathway from the dragonfy's visual system to the muscles regulating wing pitch that underly the recovery. The methods developed here offer quantitative tools for inferring insects' internal actions from their acrobatics, and are applicable to a broad class of natural and robotic flying systems.



• Z. Jane Wang, Raymond Chang, Leif Ristroph, Dragonfly Righting Reflex, APS-DFD Gallery of Fluids (2021).
• Huilin Li, Tristan Goodwill, Z. Jane Wang, Leif Ristroph, Center of Mass Location, Flight Modes and Stability of Gliders , Journal of Fluid Mechanics (2022).
• Taylor S. Clawson, Silvia Ferrari, Elizabeth Helbling, Robert J. Wood, Bo Fu, Andy Ruina, and Z. Jane Wang, Full-envelope Modeling and Analysis of Minimally-Actuated Flapping-wing Flight Journal of Guidance, Control, and Dynamics (2020)
• Mark Lee et al., Development and Validation of a Face-mounted, Negative-pressure Antechamber for Endonasal surgery, Journal of Neurosurgery (2020)
• A. El-Yacoubi, S. Xu, Z. J. Wang, A New method for computing particle collisions in Navier-Stokes flows , Journal of Computational Physics (2019) [PDF]
• R.M. Noest, Z. J. Wang, Optimal wing hinge location for fast ascent in a model fly , Journal of Fluid Mechanics (2018) [PDF]
• R.M. Noest, Z. J. Wang, A tiger beetle's pursuit of prey depends on distance , Physical Biology 14, 2 (2017) [PDF]
• A. El Yacoubi, S. Xu, and Z. J. Wang, The effect of gravity and dimensionality on the impact of cylinders and spheres onto a wall in a viscous fluid , Physics of Fluid 29, 020717 (2017) [PDF]
• S. Chang, Z. J. Wang, Predicting fruit fly's sensing rate with insect flight simulations, Proceedings of the National Academy of Sciences 1314738111 (2014) [PDF]
• A. F. Haselsteiner, C. Gilbert, Z. J. Wang, Tiger beetles pursue prey using a proportional control law with a delay of one half-stride, Journal of the Royal Society Interface 11, 20140216 (2014) [PDF]
• Z. J. Wang, On the Instability and Critical Damping Conditions, kτ=1/e and kτ=π/2, of the Equation dϑ/dt=-kϑ(t-τ), arXiv:submit/0959899 [physics.ed-ph] 2014 [PDF]
• L. Ristroph, G. Ristroph, S. Morozova, A. Bergou, S. Chang, J. Guckenheimer, Z. J. Wang, and I. Cohen, Active and passive stabilization of body pitch in insect flight, Journal of the Royal Society Interface 10, 20130237 (2013) [PDF]
• K. Varshney, S. Chang, and Z. J. Wang, Unsteady aerodynamic forces and torques on falling parallelograms in coupled tumbling-helical motions, Physical Review E 87, 053021 (2013) [PDF]
• A. El Yacoubi, S. Xu, and Z. J. Wang, Computational Study of the Interaction of Freely Moving Particles at Intermediate Reynolds Numbers, Journal of Fluid Mechanics (2012) [PDF]
• Laura Miller, Daniel Goldman, Tyson Hedrick, Eric Tytell, Z. Jane Wang, and Jeannette Yen and Silas Alben, Using Computational and Mechanical Models to Study Animal Locomotion, Integrative and Comparative Biology 52, 5, 553-575 (2012) [PDF]
• L. Ristroph, A. Bergou, A. Ristroph, G. Berman, J. Guckenheimer, Z. J. Wang, and I. Cohen Dynamics, Control, and Stabilization of Turning Flight in Fruit Flies, IMA Volume on 'Natural Locomotion in Fluids and on Surfaces: Swimming, Flying, and Sliding' [in press]
• K. Varshney, S. Chang, and Z. J. Wang, The kinematics of falling maple seeds and the initial transition to a helical motion, Nonlinearity. 25, C1-C8 (2012) [PDF]
• L. Ristroph, A. J. Bergou, J. Guckenheimer, Z. J. Wang, and I. Cohen, Paddling Mode of Forward Flight in Insects, Physical Review Letters 106,178103 (2011) [PDF]
• A. J. Bergou, L. Ristroph, J. Guckenheimer, I. Cohen, Z. J. Wang, Fruit Flies Modulate Passive Wing Pitching to Generate In-Flight Turns, Physical Review Letters 104,148101 (2010) [PDF]
• L. Ristroph, A. Bergou, G. Ristroph, K. Coumes, G. Berman, J. Guckenheimer, Z. Jane Wang and I. Cohen, Discovering the Flight Autostabilizer of Fruitflies by Inducing Aerial Stumbles, PNAS 107, 11, 4820-4824 (2010) [PDF]
• L. Ristroph, G. Berman, A. Bergou, Z. Jane Wang and I. Cohen, Automated Hull Reconstruction Motion Tracking (HRMT) Applied to Sideways Maneuvers of Free-Flying Insects, Journal of Experimental Biology 212, 1324-1335 (2009) [PDF]
• U. Pesavento, Z. Jane Wang, Flapping Wing Flight Can Save Aerodynamic Power Compared to Steady Flight, Physical Review Letters 103,118102 (2009) [PDF]
• Z. Jane Wang, Aerodynamic efficiency of flapping flight: analysis of a two-stroke model, Journal of Experimental Biology 211, 234 (2008) [PDF]
• Z. Jane Wang, David Russell Effect of Forewing and Hindwing Interactions on Aerodynamic Forces and Power in Hovering Dragonfly Flight , Physical Review Letters , 99-148101 (2007) [PDF]
• Sheng Xu, Jane Wang, A 3D Immersed Interface Method For fluid Solid Interaction, Computational Methods in Applied Mechanics and Engineering 8355 (2007) [PDF]
• A. J. Bergou, S. Xu, and Z. J. Wang, Passive wing pitch reversal in insect flight, Journal of Fluid Mechanics 591, 321-337 (2007) [PDF]
• G. Berman, and Z. J. Wang, Energy-minimizing kinematics in hovering insect flight, Journal of Fluid Mechanics 582, 153-168 (2007) [PDF]
• Sheng Xu and Z. Jane Wang, An Immersed Interface Method for Simulating the Interaction of a Fluid with Moving Boundaries, Journal of Computational Physics 201, 454-493 (2006) [PDF]
• Sheng Xu and Z. Jane Wang, Systematic Derivation of Jump Conditions for the Immersed Interface Method in Three-dimensional Flow Simulation, SIAM Journal of Scientific Computing 27.6, 1948-1980 (2006) [PDF]
• A. Andersen, U. Pesavento, and Z. Jane Wang, Analysis of transitions between fluttering, tumbling and steady descent of falling cards, Journal of Fluid Mechanics 541, 91-104 (2005) [PDF]
• A. Andersen, U. Pesavento, and Z. Jane Wang, Unsteady aerodynamics of fluttering and tumbling plates Journal of Fluid Mechanics541, 65-90 (2005) [PDF]
• David B. Russell, Numerical and Experimental Investigations into the Aerodynamics of Dragonfly Flight (2004)
• Umberto Pesavento and Z. Jane Wang, Falling Paper: Navier-Stokes Solutions, Model of Fluid Forces, and Center of Mass Elevation, Physical Review Letters 93.14, 144501 (2004) [PDF]
• Z. Jane Wang, The role of drag in insect hovering, Journal of Experimental Biology 207,4147-4155 (2004) [PDF]
• Z. Jane Wang, James M. Birch, and Michael H. Dickinson, Unsteady forces and flows in low Reynolds number hovering flight: two-dimensional computations vs robotic wing experiments, Journal of Experimental Biology 207,449-460 (2004) [PDF]
• D.I. Pullin and Z. Jane Wang, Unsteady forces on an accelerating plate and application to hovering insect flight, Journal of Fluid Mechanics 509, 1-21 (2004) [PDF]
• R.B. Bhiladvala and Z.J. Wang, Effect of fluids on the Q factors and resonance frequency of oscillating micrometer and nanometer scale beams, Physical Review E 69, 036307 (2004) [PDF]
• David Russell and Z. Jane Wang, A cartesian grid method for modeling multiple moving objects in 2D incompressible viscous flow, Journal of Computational Physics 191, 177-205 (2003) [PDF]
• Z. Jane Wang, Unsteady Aerodynamics of Insect Flight, Computational Modeling in Biological Fluid Dynamics, IMA Volumes in Mathematics and its Applications, Springer 2001
• Z. Jane Wang, Computations of Insect Hovering, Mathematical Methods in the Applied Sciences, Wiley, vol. 209 (2001)
• John Chalker and Z. Jane Wang, Spectrum of the Fokker-Planck operator representing diffusion in a random velocity field, Physical Review E, 61, 196 (2000) [PDF]
• Z. Jane Wang, Two Dimensional Mechanism for Insect Hovering, Physical Review Letters 85.10, 2216-2219 (2000) [PDF]
• Z. Jane Wang, Vortex shedding and frequency selection in flapping flight, Journal of Fluid Mechanics 410, 323-341 (2000) [PDF]
• Z. Jane Wang, J.G. Liu, and S. Childress, Connection between corner vortices and shear layer instability in flow past an ellipse, Physics of Fluids 11.9, 2446-2448 (1999) [PDF]
• Z. Jane Wang, Efficient Implementation of the Exact Numerical Far field Boundary Condition for Poisson Equation on an Infinite Domain, Journal of Computational Physics 153, 666 (1999) [PDF]
• J. Eggers and Z. Jane Wang, Crossover behavior in turbulent velocity fluctuations, Physical Review E 57.4, 4281-4288 (1998) [PDF]
• S. Succi, Z. Jane Wang, and Y.H. Qian, Clustering Instability in Granular Gases, International Journal of Modern Physics C 8.4, 999 (1998)
• J.T. Chalker and Z. Jane Wang, Diffusion in a Random Velocity Field: Spectral Properties of a Non-Hermitian Fokker-Planck Operator, Physical Review Letters 79.10, 1797-1800 (1997) [PDF]
• Virginie Emsellem, Leo P. Kadanoff, Detlef Lohse, Patrick Tabeling, and Z. Jane Wang, Transitions and probes in turbulent helium, Physical Review E 55.3, 2672-2681 (1997) [PDF]
• Jonathan Miller and Jane Wang, Passive Scalars, Random Flux, and Chiral Phase Fluids, Physical Review Letters 76.9, 1461-1464 (1996) [PDF]
• A. Sanchez, D. Cai, N. Cronbech-Jensen, A.B. Bishop, and Z. Wang, Roughening transitions of driven surface growth, Physical Review B 14664 (1995)
• Leo Kadanoff, Detlef Lohse, Jane Wang, and Roberto Benzi, Scaling and dissipation in the GOY shell model, Physics of Fluids 7.3, 617-629 (1995) [PDF]
• S. Chen, Z. Wang, G. Doolen, and X. Shan, Three Dimensional Lattice Bontzmann Computational Fluid Dynamics, Journal of Statistical Physics 68, 379 (1992) [PDF]

Editorial

• Steve Childress, Anette Hosoi, William Schulz, Z. Jane Wang, Natural Locomotion in Fluids and Surfaces: Swimming, Flying, and Sliding, IMA Volumes in Mathematics and its Applications (2012) [To Appear]
• Andrew Gilbert, Isaac Klapper, Jean-Luc Thiffeault, Z. Jane Wang, Fluid Dynamics, From Theory to Experiment, Physica D special issue in honor of Steve Childress 240, 20, 1565-1684 (2010)