  Despite many accomplishments by legged robot designers, state-of-the-art
bipedal robots are prone to falling over, cannot negotiate extremely rough
terrains and cannot directly regulate unilateral contact forces. Our objective
is to integrate merits of legged and aerial robots in a single platform. We
will show that the thrusters in a bipedal legged robot called Harpy can be
leveraged to stabilize the robot's frontal dynamics and permit jumping over
large obstacles which is an unusual capability not reported before. In
addition, we will capitalize on the thrusters action in Harpy and will show
that one can avoid using costly optimization-based schemes by directly
regulating contact forces using an Reference Governor (RGs). We will resolve
gait parameters and re-plan them during gait cycles by only assuming well-tuned
supervisory controllers. Then, we will focus on RG-based fine-tuning of the
joints desired trajectories to satisfy unilateral contact force constraints.

Robotics;Systems and Control;Systems and Control