Did you know original concept of the ibot® PMD has been around for over 20 years? The ibot® PMD was first designed by DEKA Research and Development and inventor Dean Kamen back in the late 90s. Kamen is a well-known and successful inventor, with over 7,000 patents to his name including inventions like an at-home dialysis machine, the auto syringe, and the Segway. While today the ibot® is made by Mobius Mobility, Kamen’s original multi-modal design remains the same.
One of the ibot®’s most unique modes, Balance Mode, has been around since the beginning. Balance Mode lifts users to an elevated position by balancing on two of its typically four grounded wheels. This can seem to defy the laws of gravity to some and makes the ibot® appear like a Transformer, as its wheels move over one another and it shifts into this balancing state!
While this technology has been around for years, one of the most frequently asked questions we still answer is “How does the ibot® really stay balanced?” In this blog and with the help of Kamen himself, we’ll break down the engineering behind Balance Mode and show how the Mobius Mobility team uses reliable technology to give wheelchair users a whole new (eye-level) view!
How does the ibot® PMD really stay balanced?
The short answer to the question is gyroscopes. Gyroscopes spin extremely fast and work to remain pointed in the same direction. As changes to center of gravity occur, gyroscopes resist, attempting to maintain a level position. The ibot®’s inventor, Dean Kamen, explains it best in this short video.
As Dean explains, gyroscopes in the ibot® can tell if the chair is starting to lean forward or backward and how fast it’s leaning in either direction. So, as a user begins to drive forward and the device tilts, its gyroscopes sense and adjust accordingly to maintain the balance, just as a standing human maintains balance while walking. Airplanes also use this same technology to stay balanced as they fly.
The ibot® is dynamically stable. When a user moves while seated in the device, the ibot®’s sensors and gyroscopes measure the amount of change and move the device to maintain its balance. This keeps the user constantly balanced above the center of the device.
Here are a few of our most common FAQs: Balance Mode edition.
What happens if the ibot®’s battery is low in Balance Mode?
If the ibot® becomes low on battery, it warns the user that it doesn’t have enough power to stay in Balance Mode. If the battery gets too low to maintain balance, the device will automatically transition to 4-Wheel Mode, and the user can continue to use the device to get to a charger.
What happens if the user controller loses communication with the ibot® power base?
If the powerbase loses communication with the controller, the powerbase stays powered on and actively balancing. If this happens, the power off request button will light up. When pressed, the device will transition to 4-Wheel Mode and bring the user back down to the ground.
What happens if the ibot® cannot maintain its balance?
A large shift in a user’s center of gravity could be caused by someone giving the ibot® a hard shove, or a bag getting caught on a railing and pulling the device backwards. Accidentally going over surfaces like sand or wet leaves in balance mode could also cause the ibot® to sense that it cannot maintain balance. If a shift in gravity is too large, the device will automatically transition down to 4 wheels and bring the user down to the ground.
Things to Consider
When designing the ibot®, DEKA engineers worked to prepare for every possible scenario and created transition processes to prevent the device from ever shutting down while balancing. While automatic transitions will shift the device back down onto two wheels, they can be jarring. It’s important to note that users who cannot handle a quick transition down should not use Balance Mode. For more information on the limitations on Balance Mode, please reach out to us, and a Mobius team member would be happy to help you determine whether Balance Mode would be a good fit for you!
Hopefully this blog (and ibot® inventor Dean Kamen) will take some of the mystery out of Balance Mode. If you’re interested in trying it out for yourself, please reach out to us at info@mobiusmobility.com to see if you qualify for a demo, and get ready to #reachcimbgo!
