John Baillieul PhD, Applied Mathematics, Harvard University, 1975 

Department of Aerospace and Mechanical Engineering Department of Manufacturing Engineering 15 Saint Mary's Street Boston University Boston MA 02215 (617) 3539848 johnb@enga.bu.edu 
My research interest lie in the fields of robotics, control of mechanical systems, and mathematical system theory. The following lists some current projects.
The Mechanics of Mobility
This research is being done with my graduate student Geoff Howell. The aim of this research is to identify the essential and basic components of the mechanics of controlled (powered) walking. Combining both theoretical and experimental analysis, we have developed what appears to be the simplest example of a controlled walking biped. We introduce an extremely simple, twodimensional, pendulumdriven biped robot model and study its simplest locomotion strategy. The model is inspired by the slopedriven, passivedynamic biped models of McGeer and the simplifying massdistribution assumptions of Garcia, et al. The pendulumdriven biped is composed of two identical rigid legs connected at the hip by a frictionless, unactuated hinge. A pointmass pendulum, also attached at the hip, is held by an actuator at a constant angle in front of the biped. The actuator reacts against the stance leg, allowing the pendulum to be thought of as a torso. The equilibrium gait behavior of the pendulumdriven biped on level ground is compared, via homotopy continuation, to that of the wellstudied slopedriven biped. Numerical simulation shows that the pendulumdriven biped model exhibits the same richness of gait behaviors (including perioddoubling bifurcations) as slopedriven biped models, yet its gait behavior is easier to study. The homotopy continuation method is then used to find the location of previouslyunreported stable period3 gaits for the slopedriven biped.
The B.U. Smart Wing Project
This research is being done with my graduate student Matt Lee. The Boston University Smart Wing project provides an instrumented test bed to study the use of pulsedair injection for controlling boundary layer dynamics. The aim of the research is to understand the control of fluidflow over a wing using small amounts of air, injected in periodic bursts at carefully controlled locations along the upper surface of the wing. Wings of various geometries with Reynolds numbers in the range 150,000  200,000 are being used in experiments aimed at controlling flow separation and stall at high angles of attack.
The B.U. Ducted Air Flow Experiment
This reasearch is being done with my graduate student Huajun Liu. The aim of this research is to understand the characteristics and control of fluid instabilities in a lowspeed axial compressor rig.
Further information is available at the CBD ongoing research pages. A larger list of Dr. Baillieul's publications is also available.
"Simple Controllable Walking Mechanisms which Exhibit
Bifurcations," To appear in the Proceedings of the 37th IEEE
Conference on Decision and Control, Tampa, Florida, December
1618, 1998.