  The problem of designing and stabilizing impact-free, energy-conserving gaits
is considered for underactuated, point-foot planar bipeds. Virtual holonomic
constraints are used to design energy-conserving gaits. A desired gait
corresponds to a periodic hybrid orbit and is stabilized using the Impulse
Controlled Poincar\'e Map approach. Numerical simulations for the case of a
five-link biped demonstrate convergence to a desired gait from arbitrary
initial conditions.
