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3D Printing of Low-cost Orthotics and Assistive Devices for Disabled Children J Mehlferber MFA, PhD, T Millard PT DPT, Brittany Brady Departments of Visual Arts and Physical Therapy, University of North Georgia BACKGROUND AND PURPOSE METHODS RESULTS Even the most severely disabled child can participate in typical childhood activities if provided with appropriate support. Currently, the significant variance in the level of disability makes creating individualized products time consuming and very expensive. Children, who quickly outgrow devices, can be especially challenging to help. 3D printing makes it possible to design and produce customized oneof-a-kind objects at a low cost. • An IPad camera was used for stereophotogrammetry (3D scanning to record a real-world object from multiple points of view in order to collect data on its shape). 123D Catch software was used to process the collected photographs into a digital image. Blender 3D modeling software was used to create a polygon mesh to define the shape of a virtual 3D object. The naturalistic 3D scans were combined with geometric 3D modeling to create assistive devices that created an interface between the human body and the tricycle. 3D printing is a process of “printing” a three-dimensional object using a machine that translates a virtual 3D computer model into layers of material (usually some form of plastic) that are built up, layer by layer, until a real three-dimensional form is produced. The process is similar to the way an ink-jet printer works, except that in addition to an x and y axis (left and right, up and down), there is also a z axis (outward) that moves away from the flat two-dimensional plane and into third dimension space. • The computer models (STL (STereoLithography) files) were printed by MakerWare using the MakerBot Replicator 2 Printer. The Replicator2 prints a three-dimensional object by translating the sliced virtual 3D computer model into material (PLA plastic) that is heated, extruded, and built up, layer by layer, until an actual, physical three-dimensional form is produced. PARTICIPANTS Two 5-year-old males, 2 years post ABI, and an 11-year-old male with spastic quadriparesis cerebral palsy were provided with adaptations to their tricycle to promote improved autonomy while tricycle riding. All children displayed decerebrate posturing at rest, were communicative through eye blinks and were able to initiate random movement of their extremities. The long term goal of each child’s family was to promote participation in leisure activities appropriate for their child’s age. In order to accomplish these goals the following postural problems needed to be addressed and supported: • Trunk control – How to help child remain seated without falling off the trike. • Arm position – How to promote hands on handle bars • Foot position – How to promote most efficient foot position for peddling. • Parent’s goals of increased independence were achieved. • Student’s gained valuable experience in design and implementation of adaptive devices for children with special needs. • Student’s gained knowledge and used a 3D printer to design functional objects. • Children were able to ride a tricycle which improved posture and decreased energy expenditure with minimal assistance. • Several versions of each assistive device were printed and tested. Refinements to the designs were made to improve fit and function. The final versions of the printed devices—two “hand-holds” and two “pedal-boots” allow the child to maintain a neutral hand position while grasping the handlebars, and keep the foot at a 90-degree angle to the calf while aligning the calf and foot vertically with the knee. Total cost for the four assistive devices is less than $20, based on a material cost of $48/kg for the PLA plastic. Children Selected For Project Inclusion Trial One Parent identified problems restricting cycling Brain Storming Sessions Object Development Photography EQUIPMENT Amtryke Adapted Tricycle- Used as base for adaptations 5 Gallon Bucket – Used to customize the seat 123D Catch Software – Used to create digital image of body parts MakerWare Software and MakerBot Replicator 2 Printer – Used to print final adaptations Blender Software – Used to create geometric 3D object PLA Plastic—Medium for adapted devices IPad 2 – Used for stereophotogrammetry CLINICAL IMPLICATIONS •Results demonstrate that inexpensive models of 3D printers can be used to fabricate adaptations to promote functional participation easily and quickly. •The enhancement of motor function may promote change in the motor cortex through the generation of independent movement..