[MUSIC] Welcome to the special module on mobility within the Robotics MOOC at the University of Pennsylvania. In this course, we're going to spend four weeks talking about mobility. In week one, we'll quickly, quickly understand that the animals are the key to mobility and we'll focus on limb mobility. And we'll realize to get that right, we need to think about physics and energy, and the exchange of work. In week two, we'll break down the components. Behavioral components like this pogo stick that we'll be talking about, and physical components like these strength of materials and structural properties that we'll be talking about. Don't worry. We're going to be thinking about how to put them together and build bodies with limbs out of these components in week three. We'll think about kinematics which is the study of the way limbs move in space. We'll add dynamics and so you can begin to think about these hopping machines that use pogo stick like ideas even though they don't look very much like pogo sticks. Finally, in week 4 we'll be ready to talk about what's known of programming work. How do you compose more complicated behaviors out of simple pieces? And these energy bases begin to be shaped. And as they're shaped properly, we begin to snap together different components. And as we snap together these simpler components into more complicated bodies, we anchor them into the behaviors that we really wish to achieve. Here's an example of the horizons of research, Aaron Johnson's leaping robot trying to scramble up the ledge of a table. Welcome to the mobility component of the robotics specialization MOOC by the University of Pennsylvania Grasp Laboratory.