This paper presents an overview of ongoing research on surface exploration at the GRASP Lab. We are investigating the necessary components and modules that must be embedded into a robot for it to have the exploratory capabilities required to recover mechanical properties from a surface given minimal a priori information. Eventually, this information will be used to enable a robot stand and walk stably in an environment that is unknown and unconstrained. The laboratory setup involves a compliant wrist with six degrees of freedom, mounted on a robot arm, and a prototype foot mounted on the wrist. We have successfully designed and implemented exploratory procedures (ep's) to recover penetrability, material hardness and frictional characteristics by exploring the surface.