What has six wheels and runs on water? Azaris — a new off-road vehicle prototype from Ferox. Azaris has a rocker suspension modeled after the one on the Mars rover. The problem is, linking four drive wheels on a rocker suspension would be a nightmare. The usual solution? Motors directly in the wheels. But Ferrox has a different approach.
The vehicle has a conventional BMW motorcycle engine but instead of driving a wheel, it drives a pump. The pump moves fluid to the wheels where something similar to a water wheel around the diameter of the wheel causes rotation. The fluid is mostly water and the pressure is lower than a conventional hydraulic system. Auto Times has a video of some stills of the prototype and you can see it below. We haven’t actually seen it in motion, unfortunately.
According to media reports, the pressure runs from 200 to 1,000 PSI which is a lot lower than in a conventional system. The motorcycle engine provides 100 horsepower and could be replaced by an electric motor if desired. They also quote the motors as being 98 percent efficient, although we think that means considering the energy in the water pump’s output to the wheel’s energy, not the thermal efficiency starting with the motor, as an internal combustion engine is doing great to accomplish 50% efficiency.
The selling point is that you can drive wheels using a liquid drivetrain that is supremely flexible. This allows you to do things like the rover-style suspension that would ordinarily require heavy motors in the wheels. The liquid motors are about 24 pounds each. Equivalent electric motors could weigh up to 66 pounds. The motorcycle engine doesn’t even max out the amount of power the wheels could deliver, so there’s room to grow.
These are prototypes and not for sale at the moment, unfortunately. They are simply to showcase Ferox technology. We couldn’t help but wonder if anyone has tried a similar scheme for a robot or other hacker drivetrain?
We’ve seen water power charging a cell phone, but that’s hardly the same thing. We also saw some pretty conventional but tiny hydraulics in this model excavator. The idea is the same though. Use hydraulics to move something with a remote motor.