How Jake Laser Built Robot Legs That Let His Dad Reach Trails and Stairs Again

Jake Laser grew up watching his father face constant barriers from a wheelchair. Multiple sclerosis had attacked nerve signals to his legs decades earlier, ending a life that once included marathon running and hiking as a chemical engineering professor. Simple outings turned complicated fast. Stairs and curbs created hard stops that no standard chair could clear.

Jake had always wanted to better things, and as a kid, he experimented with cardboard bionic legs. A few decades later, as a seasoned maker with a long list of fancy undertakings under his belt, he set out to find a genuine solution. He was drawn to a high-end Unitree quadruped robot with industrial-grade wheels at each foot on the legs. It would glide effortlessly across a smooth floor before transitioning to stepping when it encountered uneven terrain or a barrier.

Weeks of intense work transformed the robot into a personal mobility rig. Jake placed a racing bucket seat high up onto the central frame, leaving the mechanical legs unimpeded underneath. He also attached his father’s legs in a stable position in front of the robot so that he could ride. The entire outfit was held together by a heavy-duty harness that would keep him safe if anything unexpected happened or if there was a violent jolt, and because the machine was designed for transferability, it could crouch down nice and low before returning to full height.

The fun part was giving the whole thing personality by adding some carbon fiber trim here and there, and the curved panels were a conscious reference to 1940s automotive designs. The front also had some beautiful vintage-style chrome headlights. Then there were the underglow lights and the magnificent spinner covers on the wheels, which provided all the visual flair you could want without compromising functionality. Overall, the ultimate result appeared to be a bike made just for one rider, rather than factory-standard equipment.

The project was relatively low-key in terms of software, but the core of the issue was that the robot’s balance system was entirely based on sensors that kept the thing stable no matter what it was doing, but when a human boarded, the entire system needed to be re-calibrated to account for the extra weight and new center of gravity. The modifications allowed the machine to remain upright and steady regardless of the terrain it was on. The forward, backward, left-right, and rotation commands were executed via a wireless joystick controller. Height adjustments allowed the rider to lower it for easy entry or elevate it for tough terrain. It seemed somewhat familiar, like driving a high-end remote control car, but with legs instead of wheels.

Of course, things didn’t go quite as planned at first; finding the perfect balance was a big struggle, and a few first test runs resulted in the thing tipping over a few times, but with some adjusting and repeated testing on all types of terrain, and I mean all sorts, things began to come together. The hybrid drive proved to be quite useful. On level terrain, the wheels performed admirably, providing ample speed and power efficiency. When things grew rough and bumpy, the legs took control, lifting and planting the machine accurately. His father finally went for his first ride, and his reactions were immediate, as he was amazed by this thing. Comments of awe accompanied each fresh expanse of area covered. The machine took him up steep hills, over hard rock, and into sections that had been off-limits for 20 years, including a very hairy complete staircase.
[Source]