When Toyota put up its i-Road for testing in 2014, it was more as an answer to urban road traffic gridlock. Sized as large as the larger fleet of motorbikes, it has seats for two people like any conventional bike – just that the entire seating was enclosed in a cockpit. With absolute competition driving in through Piaggio’s MP3 and Nissan’s Land Glider, there was one common aspect binding these three-wheel electric vehicles – their active safety systems. In the second of our series on three-wheel electric vehicles, our bloggers discuss active safety control systems and the patents powering them.
In the previous blog we discussed the advent of three-wheel electric vehicles and the increasing use of tadpole technology. While we delved deeper into this topic, we found that the technology in these three-wheelers could be bucketed into two sections of active and passive safety systems.
Active safety systems include a string of technologies related to steering control, brake control, stability control, warnings and alerts among other smaller stuff. In fact, at least 41% of the innovation in the global space of safety controls for three-wheel electric vehicles is related to active safety mechanisms.
The area of Active Safety Systems has a wider spectrum compared to Passive Safety Systems. It is interesting to note that around 64% of patent applications included both active as well as passive safety mechanisms in the three-wheeled electric vehicles.
Tilting with power
One of the primary aspects of biking is the tilt effect. However, in a normal bike, this often is a cause for accidents considering that the rider needs to have the most control on the vehicle during tilts and turns. Three-wheelers with a single wheel in the front are also prone to accidents while tilting primarily because of its understeer quality.
In a scenario when one needs to brake hard, especially during a turn, having two wheels in the front helps understeer the vehicle faster, reduces the skid factor of the single back wheel and distributes the weight evenly across the vehicle, adding to the stability.
Hence, while steering is possibly the most effective with a single front wheel as in a delta design format, stability during tilts is the most effective in tadpole designed three-wheel electric vehicles. Another point where the tadpole gains over the delta is in the placing of the motor and the batteries. With just a single wheel in the front and the motor right there, the vehicle may require the batteries to be shifted to the back for more equitable weight distribution. This means that the motor cables need to be drawn all the way through the body of the vehicle from the front to the back. A tadpole design however, allows for about 30% of the weight of the vehicle to stay on the drive wheel, making it a near hands-down option for a three-wheel electric vehicle with enhanced safety.
It’s no surprise that companies such as Piaggio, Ford, Bombardier, Honda and Toyota own the maximum IP assets in active safety systems. The below video says why:
Considering that the braking system is definitely a better option while braking, it has been found that Bombardier and Honda own the largest share of patents in Front Wheel Control, while Piaggio and Honda lead in patented technology for Rear Wheel Control. The below chart dissects the percentage share of patents across the various aspects of active safety controls in the global landscape.
Tilt and lean control does make up for a chunk of inventions in active stability systems. Going back to the global patent landscape, we found over the last five years, barring Aisin, the other top four players in this space have been showing an increasing interest to enhance safety during tilts.
Another interesting trend to notice in this global landscape is that around 88% of the patents are filed between 2000-2015, where more than 50% of these innovations marked their filings in past five years (i.e. between 2011-2015). Going by this trend, we soon expect a lot more new innovations to come up in the domain of stability for electric three-wheeled vehicles.
With Britain already experimenting with a road that allows electric vehicles to charge on the go, three-wheel electric vehicles are poised to grab a fair share of the market from the sheer standpoint of their compactness that allows them to maneouver easily in traffic gridlocks, the cockpit safety that they offer the riders and the smartness that they exude.
(Featured image source: https://commons.wikimedia.org/wiki/File:2013_Toyota_i-Road_01.jpg)