If you've perused the powerchair market lately, you've probably noted that six-wheelers have come of age, with models from virtually every manufacturer, in application from light- to high-end rehab.  It's an evolution that took decades, but for users now benefiting from six-wheel technology, the platform was worth the wait.

Six-wheel powerchairs are nothing new, stemming from Europe in the 1980s, as small, highly-maneuverable powerchairs, with drive wheels centered under the user, and front and rear casters.  While such a configuration served well indoors - affording turn-on-center performance and absolute front-to-rear stability - outdoor use was limited.  In a rigid six-wheel design, if one end of the powerchair lands on a different plane than the other - say, the front casters are on the downside of a threshold, with the rear casters remaining in the doorway - the center drive wheels can high-center, suspended off the ground, rendering the powerchair immobile.  As six-wheel technology evolved, removing the tendency of high-centering was among the foremost design challenges.  After all, for many active users, a powerchair that can't transverse slightly uneven surfaces isn't acceptable mobility.  Designers and users alike, however, saw the values of a compact turning radius and maximized stability, fueling the pursuit to increase the performance of six-wheel mobility. As six-wheel technology evolved through the 1990s, and into the 21st century, suspension was added to front casters on center-wheel drives, and to rear casters on rear-wheel drives, enhancing performance of the six-wheel variations.  However, all of those variations retained a fixed set of casters, meaning that once the suspended casters reached maximum travel, as with descending a threshold, they combined with the other fixed casters to still lift the drive wheels off the ground.  Six-wheelers were better, but remained less practical toward maintaining traction on uneven terrain than front-, mid-, and rear-wheel drive powerchairs with only four wheels. The evolution continued, drawing from suspension theories within the mobility industry and others, whereas if the front casters raise, and the rear casters can effectively travel via suspension, as well, the drive wheels then maintain enhanced contact, especially if they, too, are driven toward the ground via suspension - all of which creates a pliable six-wheel powerchair.  As a result, more-advanced six-wheelers today feature front casters that all but intuitively surmount obstacles, rear ends that compress and articulate, and drive wheels that strive toward sound grip on varied surfaces.   The result is inspiring, with the evolution of the six-wheeler mobility platform transcending from impractical to liberating, offering consumers yet another defined mobility choice. So, much like the coming of age of all mobility platforms, when we consider six-wheel technology, one question remains:  If six-wheelers offer optimal maneuverability, stability, and handling, why don't they obsolete all other powerchair platforms? The answer is found in the diversity of the market, and the exclusive limitations within every product.  Even with high-end suspensions, many six-wheelers still have a more difficult time backing up obstacles or handling very steep transitions than the other mobility platforms, with the front and rear casters working against each other, potentially high-centering the drive wheels - this can prove especially an issue on less-than-ideal vehicle lifts and ramps.  Further, six-wheels on the ground can cause excessive noise and vibration on rough surfaces, and, in very rough outdoor surfaces, some six-wheelers may still high-center much quicker than their more traditional four-wheels-on-the-ground counterparts.  For these reasons, there remains tremendous merit within other mobility platforms for many users based on their lifestyle needs. When it comes to six-wheeler selection, it's exceptionally important to trial products, as performance varies widely, not only from brand to brand, but also from model to model.  Whether it's indoor, outdoor, or all-around performance you're looking for, it's a wise investment to put prospective six-wheelers through their paces, forward and back, ideally in your own environment, fully determining whether the performance characteristics are right for you. The fact is, no one can tell you that one mobility platform outperforms all others, all of the time - and this holds true for six-wheel technology.  However, no matter if you're a light- or high-end user, you owe it to yourself to add six-wheelers to your range of mobility considerations.