An exoskeletal robot may soon replace the wheelchair for people in need. Already, Ekso Bionics’ current robot allows users to walk and interact with society. This prototype enhances the human experience with 3D printed parts that connect body to robot. These parts were created by referencing a 3D body scan, providing an accurate, symbiotic connection to the body. The parts are ventilated with a complex pattern, allowing the skin to breathe, while keeping the product weight minimized. Finally, the parts add grace and fluid lines to an otherwise mechanical robot, visually bridging the void between biology and technology.

The goal was to create parts to connect the body of a paralyzed user to a robot as naturally and respectfully as possible. This required the creation of custom, 3D printed parts that would envelop the body in exact locations to provide balance and support, while carefully avoiding areas prone to bruising. The fixed interstitial parts had to improve the robot’s donning and doffing speed and simplicity, preferably avoiding all of the current Velcro straps used in the production units.

The parts would have to be custom printed for each user, yet easily implemented broadly and template-driven in order to create many more mass-customized units. 3D scanning a paralyzed user requires suspending that person for the duration of a scan, then digitally compensating to simulate the morphological changes a body makes when supported by robot and skeleton. Finally, the 3D printed parts must be strong enough to hold the body in various states, while remaining flexible enough to provide comfort at each contact region.

A final design intent was to visually mitigate the brutal, mechanical geometry of the robot, by printing forms that suggested a more human and fluid quality.

An exoskeletal robot provides a partial solution for a user with mobility needs. To more fully address the needs of the individual, it must integrate that user directly into the robot, and its very creation must be driven by the uniqueness of that unique person. It must reflect both their physicality as well as their personality, inviting them to customize various patterns and designs that infuses their robot with individual form and style.

By 3D scanning the body, we can create an even distribution of pressure about the musculature of the legs, which are highly sensitive to uneven pressure, despite the lack of tactile sensation. The pattern allows the skin to ventilate, which reduces sweat buildup, reducing friction and the risk of infection. The spinal section was created by a digital average between a standing scan and a seated scan, intending to conform accurately and comfortably to the upper body. Handles were designed into the printed parts, though disguised into the overall form of the products, diminishing the visual ‘handle’ element and its connotation. The filigree lines are irregularly striated, suggesting the musculature that such parts replace. And the overall printed forms intend to showcase the fluidity of the body and natural forms, mitigating the rigid mechanical forms of the robot.

Creating interstitial parts that connect body to robot encompasses a broad range of technologies and disciplines. First, we worked with kinesiologists to understand the body motion and the challenges that would be faced as we held the body into a robot with semi-rigid parts. We then researched those regions of the body which could be used as ‘contact regions’, creating a gradient map to inform the shape and location of the safe areas on the body to be contacted. We studied the ‘sit-to-stand’ process for the body and robot, learning how the robot lifts the body from a seated position, when the greatest load would be placed on the interstitial components. We researched the sweaty regions of the body, enhancing ventilation in those areas, while structurally reinforcing them to compensate. We worked with Amanda, the robot’s ‘test pilot’ to find designs and patterns that appealed to her and complemented her sense of fashion.

The ‘test pilot’s’ body was 3D scanned using a 3D Systems Sense 3D Scanner. She was placed in a scaffold that held her body in an orientation that mimicked the robot stance. She was scanned multiple times, both seated and standing, since her use of the robot would include both positions, and neither could cause bruising or discomfort. The ‘point cloud data’ generated by these scans was then turned to usable 3D surface geometry using 3D Systems’ GeoMagic Studio software. This 3D surface model of Amanda became the reference underlay for all of the organic surfaces that would follow. This model was then imported into 3D CAD software and assembled digitally into the CAD file for the Personal Ekso robot. The design then involved creating geometric forms that borrowed from Amanda’s body scan and the robot’s CAD model, coupling the two otherwise dissimilar forms. Scale models and test parts were routinely printed using 3D Systems ProJet 3500. The final 3D printed parts were created using a 3D Systems Sinterstation Pro, using Nylon 12 powder. Once parts were created and assembled to the robot, a physical therapist closely monitored Amanda’s motion, closely observing the effects.

We feel that powered exo-skeletal robots will replace wheelchairs, once fully matured. Once the basic mechanical and neuro-mechanical functionality has been met, the next great challenge will be to transform this device from what would otherwise be a mechanical walking contraption, into something more akin to fashion eyewear: vital, functional, yet personal and beautiful. It will be worn by millions of people in need, yet it will subtly, fluidly, elegantly integrated into their lives. Achieving this is a design challenge. The robot will need to communicate a message of respect and beauty, downplaying its medical/mechanical nature.

It may also be that a 3D printed robot may reduce costs, since printed parts allow the integration of many components into a single, highly complex one. This further benefits those in need, since the current complexity out-prices most potential users. Furthermore, the component consolidation may reduce the robot’s size and weight, thereby increasing battery life while allowing greater discretion for the user.

We can envision a day when anyone in the world in need of an exoskeletal robot simply visits a clinic for a body scan, much as one might visit an optometrist for an eye exam. The visit would involve the choosing of design and pattern, allowing the user to co-design their robot virtually. The resulting robot would exist as much as a product of their body as their taste, and be worn throughout the day as if nothing more than a smart pair of pants.

The current robot attaches to the body using thick, Velcro straps and nylon webbing. This requires a complex sequence of steps for attaching to the body, since it was made to fit a range of bodies more than any one in particular. This also results in sweat buildup, which can lead to a range of discomfort and skin problems for a paralyzed user. The users we spoke with expressed a strong interest in discretion, once they were restored to even that first stage of walking. The desire was to look less like a medical/technological novelty, and more to appear as a person, with minimal distraction. They asked that the robot appear less like a bulky robot, and more like something intended to be seen, or at least, could be discretely hidden beneath clothing.

The steamlining of the donning/doffing process represented another high priority for users. Since this robot will potentially be worn for every step they take throughout the remainder of their lives, the ease of use at every stage becomes that much more critical. And since we are able to create a robot that conforms perfectly to the contours of the body, adjustment or tiresome strapping efforts are no longer needed. Ultimately, this makes the robot fit that much more fluidly into the lives of a user.

The Personal Ekso is inherently expensive, due to the collection of motors, computers, assembly and mechanisms comprising it. That said, printing ‘monocoque’ parts can reduce many parts and assembly steps into fewer components, thereby reducing overall product cost. This becomes especially possible for children, where their smaller and lighter bodies require even less mechanical mass, allowing greater savings. And as the Ekso grows more desirable due to the improved quality of life offered by 3D printed components, the demand for such product stands to increase.

We are finding that wheelchair-bound individuals treasure the great freedoms offered by the Personal Ekso, enabling them to once again walk with relative ease and interact with society eye-to-eye. The technology exists in only a nascent state currently, and the path is set for ever-greater motion as the technology matures. Body-driven, 3D printed components stand to improve that quality of life still beyond that, by allowing a lower cost, a more comfortable product, and a sense of individuality otherwise unachievable in such a personal product