Sol,Ben Ryan's son,a below-elbow amputee,should only use artificial limb after 1 year old, but Bennoticed that his son hadn't used his left arm. He understood what it meaned, Sol would totally lose his arfunction if he didn't make it a habit of using left arm and exercise arm muscles. So Ben made a simple arm for Sol with sponge.
Later, Ben started to learn 3D modeling, and creat a suitable a artificial limb.
In order to creat a safe artificial limb without batteries, Ben searched a lot of information on the internet and eventually found suitable methods----move it with fluid pressure. He designed hydraulic arm with modeling software, and printed them with desktop 3D printer. Ben was able to do experiment for many hydraulic arms by 3D scanning arms and legs. Alison Hutchins from RS said:"We saw the warm and touching story about Ben on television news, and later contacted Ben through Linkedin." This father created a an artificial limb-company after RS helped to design a 3D printed hydraulic arm.