Exo or Not?

There are a lot of types of robots out there, and while I’m partial to exoskeletons, which one I would choose to build depends fully on the task at hand.  There are many places where other robots have the advantage over exoskeletons.  In more static environments, arm robots provide speed and accuracy that humans cannot match.  In robotic-assisted surgery, robots enable smaller incisions and more stable control of the end effector.  And in terrains where humans may not be able to go, such as space or the bottom of the ocean, robots become our means to access these places.  To our credit, we engineers have built robots that have extended our reach on Earth and throughout the universe and augmented our human skills to perform incredible feats. However, there are some instances where we engineers have missed the mark..

When carrying supplies into a warzone, we thought it was a waste of energy to have a soldier carry their own gear.  In response, Boston Dynamics developed Big Dog, a robot that could carry a lot of weight to ease a soldier’s burden of carrying.  Big Dog was a brilliant robot with complex sensing and actuation that allowed it to remain stable when kicked and move over rough terrain. However, it turned out that Big Dog was too noisy for the job and soldiers wanted to keep their essential gear on their bodies where they cannot be separated from it.

Big Dog Robot, Boston Dynamics (bostondynamics.com/legacy)

In response, HULC and GaurdianXO (Sarcos) were created to allow soldiers to carry the load right on their bodies, keeping it safe and close.  Utilizing some of the power of the soldier’s body to accomplish the tasks meant less power was needed by the robot, which resulted in a quieter device that fulfilled the user’s needs.

Fulfilling the user’s needs should be our priority. For some assembly environments, we have created robots that can paint, move parts, tighten bolts, and weld seams. These robots fulfill the user’s needs usually by sitting in one place and doing mind-numbing, joint-damaging repeated work.  In other environments, this is not what is needed. When assembling a ship, for example, a base for an arm robot cannot be erected just to finish the welds along the inside corridor or to carry the cabling from one end to the other.  In this instance, exoskeletons fulfill the user’s needs. Exoskeletons fit close to a person and allow for assistance without the large footprint or installation requirements.  The lack of large footprint and installation is also a benefit in the medical rehabilitation setting. Exoskeletons can fulfill the user’s needs in a wide variety of situations.

One of the most important reasons to utilize exoskeletons and other robotic devices is to leverage the user. As with all engineering, and robotic engineering in particular, it is critical that we first examine the requirements of the user before determining what type of robot to build, what that robot will do, and what the robot needs to look like.  The best way to do that is get out from behind our computers, get out of our labs, get out of our offices and visit our users in the environment they need our device. We need to listen carefully to what they are saying and ask them questions and listen to their answers. This is difficult, expensive, and time consuming, but the effort pays off in the product people want to use.