A group of students from the Stanford Student Robotics club’s Extreme Mobility team at Stanford University has unveiled a four-legged robot. The robot has been dubbed Stanford Doggo, which can perform acrobatic tricks and can also traverse challenging terrain. The main purpose of the invention is reproducibility. Stanford Doggo is different from other robots because it can consult comprehensive plans, code and also supply a list that students have made available online for free.
“We had seen these other quadruped robots used in research, but they weren’t something that you could bring into your own lab and use for your own projects,” reported Nathan Kau, a mechanical engineering major and lead for Extreme Mobility in a statement. “We wanted Stanford Doggo to be this open source robot that you could build yourself on a relatively small budget.”
Stanford Doggo is the size of a beagle and it can trot, hop, jump, dance and also perform an occasional backflip. The team of Extreme Mobility estimated its cost to less than $3,000, inclusive of manufacturing and shipping costs. Moreover, all its components can be brought online. Allegedly, similar robots cost tens or hundreds of thousands of dollars, in addition to customized parts, but the affordability and accessibility were one of the key components for the Extreme Mobility team.
The students built the robot from scratch, in order to make it replicable. Reports suggest the team spent a lot of time in researching easily attainable supplies and testing parts without relying on simulations. Although the first steps of the robot were toddling, the robot can now maintain a consistent gait and expected trajectory when it encounters different terrains. The motors of the robot sense external forces and determine force and torque which each leg should apply in response. These motors recomputed at 8,000 times a second and are necessary for the working of the robot’s signature dance, which is a bouncy boogie that hides the robot’s springs. The motors act as a system of virtual springs, they are smooth but rebound the robot into proper form when they sense the robot is out of position.
Especially noteworthy is the robot’s jumping prowess; it effortlessly jumps up to 2 feet in the air, advanced working on the robot’s software made it capable of jumping up to 3 and then 3½ feet off the ground.
“This was when we realized that the robot was, in some respects, higher performing than other quadruped robots used in research, even though it was really low cost,” reported a team person.
The team is continuing its work on the robot in order to test new control systems on a second Stanford Doggo in collaboration with Robotic Exploration Lab at Stanford. The team has also finished a robot which is twice the size of Stanford Doggo, it can carry six kilograms of equipment and is called Stanford Woofer.