MindWalker Brain-Controlled Exoskeleton Puts The Paralyzed On Their Feet

An eight week EC trial of a brain-controlled exoskeleton potentially promising newfound mobility to those with lower-limb paralysis will finish this week, with the project expected to spark a five year development path to a commercial version. The device, dubbed MindWalker, is the handiwork of a seven partner team coordinated by Space Applications Services, which has been working for the past three years on a motorized exoskeleton that can be controlled and navigated via brain impulses. Now, New Scientist reports, the European Commission will assess the results, having funded the project so far.

The MindWalker is made up of two companion projects, as the name implies. Arguably more straightforward is the exoskeleton side, which has been designed to support the weight of an adult, keep them balanced when walking, and adapt to different walking styles. An integrated brain in the walker itself helps spot obstacles that could present an issue for the user.

However, more complex is the mind-reading part, which the team refers to as the Brain/Neural Computer Interface (BNCI). A non-invasive system, using a dry EEG cap that doesn't require messy gels or intrusive surgery, the technology cap is paired with a portable amplifier to make sure the computer gets the right signals. Previous methods have also included flickering diodes that gage intention to move by where the eye pays most attention.

The training process begins before the user has even strapped into the exoskeleton, however. The MindWalker team has developed a virtual reality training package which allows potential wearers to train their brains to get the most out of the BNCI link. As well as creating virtual obstacle courses to navigate through, the training system also includes a motion-actuated seat so that they become used to the sensation of being moved around by the motorized legs.

The dual development means that, even if mind control isn't suitable for a particular user, that doesn't mean the exoskeleton itself is out of reach. A more rudimentary control system – with pressure pads on the sides, triggered by rocking within the harness – to move each leg is also possible.

With brain control, though, there's a lot more finesse up for grabs. The EEG system can apparently differentiate between the aim to move slowly or at speed, meaning pace could be controlled simply by thinking differently. Down the line, it could mean expanding the system to users with even less mobility, potentially including those who experience full body paralysis.

So far, the EC has pumped €2.75m ($3.6m) into the MindWalker project over the course of around three years. It's still a long way out from commercialization, however, and the estimate is that it will take another five or so before a production version could be ready. By that point, project member Thomas Hoellinger suggests, the system could be a lot more aesthetically discrete, with less weight, smoother movements, and potentially even a frame that could be disguised under more traditional legwear.