What you are seeing is a product of the Walk Again Project. The Verge has an in-depth look at this promising technology:
This demonstration is the debut of the Walk Again Project, a consortium of more than 150 scientists and engineers from around the globe who have come together to show off recent advances in the field of brain machine interfaces, or BMI. The paralyzed person inside will be wearing an electroencephalographic (EEG) headset that records brainwave activity. A backpack computer will translate those electrical signals into commands the exoskeleton can understand. As the robotic frame moves, it also sends its own signals back to the body, restoring not just the ability to walk, but the sensation as well.
If you're interested, the whole fascinating Verge report is well-worth reading.