Don’t blink or you’ll miss it – and if you feel your skin crawl at just the thought of the darting of insects, you might be happy that you did. However, what we’re showing you here is not the super sized cockroach of your worst nightmares, but rather the X2-VelociRoACH!
Weighing in at 54 grams, it is by far the fastest legged robot of its size. This little creature moves 4.9 meters per second and its legs scurry in the fullest sense of the word. Creatures with legs (as opposed to those that fly or run on wheels) have two options if they want to go faster, as you most likely know from experience. Either they can take more steps in a shorter period of time, the Chihuahua approach let’s call it, or they can take longer steps in order to cover the distance in less time, the Great Dane method.
When designing a cockroach, there are restrictions based on the muscoskeletal system that only allow a maximum number of steps to be taken in a given period of time and so cockroaches tend to take the same number of steps while varying the length of their stride (I know, not the most pleasant thing to imagine). However, the team at UC Berkeley‘s Department Electrical Engineering and Computer Sciences’ Biomimetic Millisystems Lab wasn’t designing a cockroach, as those already exist; instead, Duncan W. Haldane and Ronald S. Fearing were designing a robot and so were not constrained by biology.
They were instead obliged not to vary the stride length of their legged creation because the legs are connected directly to the motors. Therefore, they explored the other option: number of steps taken. They maxed out at about 45 stride cycles – a wonderful bit of jargon invented to talk about the steps taken by a robot that requires motion based on circular rotations of a mechanism – and destroyed the record previously in place.
The only thing stopping them from upping the number was the laws of physics. It is certainly possible to program the creature to produce more leg cycles per second. The down side is that bits and pieces start to fly off, leaving you with significantly less robot than needed. This material failure has led to an exploration of possible 
materials that can handle the stresses of such hyper scuttling.
“More dynamic performance from this robot is achievable,” the researchers say, in terms of stride frequency–if they can find ways to enhance processes or materials.
The legs on the VelociRoACH are made of fiberglass and key structures are made more robust by using 3D printed parts and it’s only the material composite that is used that fails once the robot reaches its top speeds. As the boundaries of printable composite materials continue to expand, the upper limits of the robot’s stride cycles will also rise. This means it most likely won’t be long until another team comes along with an even faster creature.
However, VelociRoACH will always have a special place in my heart…as long as it never comes scurrying out from behind my refrigerator.
What do you think about this incredible robot? Discuss in the VelociRoACH forum thread on 3DPB.com.
