That Uni-Cub is very impressive! It reminds me of a Segway, but one that's potentially usable by disabled people because it doesn't require standing as the Segway does. Perhaps add a hand-hold and you are all set.

Even after driving (riding?) a Segway, I had mixed feelings about it. Very impressive technology, but it cost around $5000, and didn't really do anything that a $200 bicycle couldn't do; but the Uni-Cub has much more potential.

No word yet on the cost of the Uni-Cub; seems Honda is only leasing them for now.

FYI a seat can be added to the Segway. I meet a person with limited mobility using a Segway as an alternative to a scooter.

It's very interesting. The hands free operation and multi-directional drive system could make it excellent for use in places such as a kitchen where most mobility aids are awkward.

The video only showed it being used on relatively smooth surfaces. I wonder how it works on rough surfaces such as bad sidewalks, gravel driveways, grassy yards, etc.

I do not think the Uni-cub would work well outdoors, give the complexity of the drive wheel. I did just find this: Sui Generis Segway This looks like the best thing I have yet found for outdoor use. The Lyric Motion Run3r I used over the winter is hampered by it's small wheels. It requires a significant level of mid and upper body strength to control and utilize the built-in lean system.

As I search, I am finding a number of Segway-based seated versions. Models based on the turf tire Segway seem to have great rural mobility. Genny Mobility
The less expensive company I have found so far is this: Glide Saddle

I wouldn't consider a $1450 glide saddle seat an inexpensive option when one still has to buy a rather expensive Segway to make use of it.

There have been DIY / home made Segway clones. Some have open sourced their software and most use a modest amount of inexpensive hardware for stabilization and control. I could probably make a Segway like platform and stick a bucket seat on it for much less than the $1450 for just a seat.

However, scooters with 3 wheels have a significant advantage. They are still stable when not being operated. I like being able to get off my scooter and sit on the ground or floor next to it and then pull myself back up onto the scooter. I can also squeeze the brake lever and then push myself off my scooter to get back to a standing position.

All good points, Todd, and no doubt these are expensive. I have heard that hub motors have a limited life-span due to the continued impacts of road irregularities eventually dislodging motor magnets. What is your take?
I like the x2 Segway Turf large tires, giving them good grass, sand, snow capabilities. Do you think your trike can be adapted to tires with larger diameter and width?

Everything has a limited life span, but in hub motors, magnets are usually epoxied in and having them come loose is a very rare failure unless the motor was overheated. Epoxy will soften around 200F. Overheating to the point of epoxy failure will also degrade and weaken the magnets. Better motors and controllers now incorporate a thermal sensor and start limiting power before one overheats it to the point of damage.

A more common magnet related failure is corrosion. If the motor isn't sealed or a seal fails and it takes in significant water the magnets will rust. The gap to the armature should be very tight, especially in better quality motors, and if the magnet starts flaking the armature will rub. If it sits for a long time rusting it might even seize up.

There are many different hub motors, some are very cheap and poorly made and may fail quickly if exposed to harsh weather.

The most common point of failure is worn out gears in geared motors. They are usually designed to be easily replaceable, though most people probably don't try.

Many direct drive motors are nearly bullet proof. I've got 20,000+ miles on one of mine and it was only $100.00 sold as a 750 watt motor and I run it at 5000 watts. This is with year round use on Chicago streets - lots of pot holes and salted roads in winter. I did have to replace the bearings once at 15,000 miles, cost about $10 and took a couple of hours. I used a higher grade of bearing than stock so it should go quite a bit longer this time.

As for tires, each of my frames was designed for a certain diameter front tire with some clearance from 0.5" to 1.0" limiting tire choice to a small range of diameters. I build my forks without taper so the tire can be as wide as the shoulders on the motor axle, typically 4", though I recently got some wider motors which I'll be playing with soon.

In the rear it's more flexible. My rear axles are sleeved and removable so going to a wider axle for wider hubs is easy. My decks are wood and can be trimmed with a jig saw if needed to make clearance for a larger diameter tire.

Also, changing tire diameter only in the front or rear will tilt the scooter changing the head tube angle and thus affecting steering geometry. In general as the rake increases high speed stability is improved but low speed turning feels heavier and less responsive and wheel flop increases.