3D-printed exoskeleton could offer a helping hand to children with disabilities
Sometimes it takes a childish question to bring out the obvious.
The question for Dr Matt Dickinson of the University of Central Lancashire was: “Why isn’t there a special shirt that children can wear to help them move?”
The query and a rough design was provided by Christina, a student participating in the primary engineering competition, who combines children’s imaginations with the engineering expertise of companies such as Rolls-Royce to find solutions to problems in the field. world.
“I immediately saw then that she was obviously referring to some type of exoskeleton,” Dickinson said. “I thought there were millions of them, they’re all over the world.”
After doing some research, however, he was shocked to find that nothing came up to specification. Christina’s cousin has spinal muscle atrophy and needed extra support to balance and move.
After initially exploring aluminum as an option – “that would have been stupidly expensive” – Dickinson decided to build a device using 3D printed materials, and is now testing it with Tinius Olsen Testing Machine Company of Pennsylvania.
The exoskeletons have already been printed. An example from the American company 3D Systems is the Ekso suit, a motorized device intended to restore mobility to paralyzed users. Other projects, such as the one at Transilvania University in Brasov, Romania, have printed components for exoskeleton robots used for elbow joint rehabilitation.
Unlike other devices, however, Dickinson’s exoskeleton is a passive assistive tool with no electrical components. Described as a “ big helping hand, ” it provides increased mobility and strength by supporting the upper body and keeping it balanced.
It includes a rear “spine”, with neoprene between the spinal segments. As the upper body bends, some of the force is distributed across the entire imprinted spine, which “locks” into position. Neoprene connections help provide left and right support, as well as forward and backward.
Dickinson chose a polylactic acid composite material as the base, printed using a molten deposition pattern, which heats and extrudes the material layer by layer. However, the material could potentially seep into the skin, so the parts in contact with the body are coated with antimicrobial copper. 3D printing allows for quick build, updates and repairs, as well as design customization for bespoke needs. In the future, Dickinson hopes to include non-Newtonian forms, which are mostly soft but harden as soon as a load is applied.
Materials and design are subjected to extensive testing at Tinius Olsen. “What we want to be able to do is look at the level of load on the muscle by looking at strain gauges attached to the lower limb system,” Dickinson said. The test also uses force plates to assess the load on the user’s muscles.
The project is targeting human trials in June and has drawn attention to applications beyond children. This could be a potential treatment for survivors of stroke and other related medical conditions.
Dickinson also now sits on the American Society for Testing and Materials Exoskeleton Standards Committee, along with partners such as the U.S. military, and the design has even caught the attention of NASA. The combination of a 3D printed exoskeleton with a copper coating might be suitable for astronauts heading to Mars, for example, with the device providing muscle support and the copper preventing degradation from bodily perspiration.
So the 3D printed exoskeleton could move from the classroom to the surface of another planet.
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