Technology & Systems
GM Concept Gets "Hy" - Wired... and it Rides on a Skateboard
By Andrew Gardner; / photos courtesy General Motors
Jun 21, 2003, 01:10 PST

From the ground up, the Hy-wire was designed to be the most forward thinking automobile on the planet. It uses a powerplant of the future, rides on a very unique chassis, and looks like something you will someday drive on the moon. The name Hy-wire is a contraction of the vehicle’s two key technologies: a hydrogen fuel cell, which powers an electric three-phase motor; and by-wire technology, which directs all the driver’s commands to the vehicle’s operating systems.

The fuel cell stack consists of 120 individual fuel cells connected in series. The electrons extracted there, from the hydrogen molecules, allow the asynchronous electric motor to produce up to 60 kilowatts (about 80 horsepower) and up to 159 lb-ft of torque (it is interesting to note that, while internal combustion engines typically produce similar values for power and torque, when expressed in horsepower and lb-ft, but electric engines produce a far higher value of torque than of power when expressed in those same units). The high torque should ensure reasonable off-the-line response, while thee low power rating will limit the top speed. These performance characteristics, coupled with the Hy-wire’s complete lack of any emissions, make this vehicle an ideal city driver. The second half of the car’s name, “wire,” refers to the by-wire technology, which is used extensively throughout the Hy-wire. By-wire technology utilizes electrical impulses, rather than mechanical cables or hydraulic fluids, to send driver inputs to the car’s operating systems. By-wire technology is already used by some automobile manufacturers – for example, BMW recently began using by-wire throttle control in its vehicles. But GM went way ahead of the rest of the field by making by- wire technology the only connection between the driver and the car. The result is a very unique driving experience.

All the driver’s controls are concentrated in one control unit. Instead of a steering wheel and pedals, the driver will find two handgrips, which he or she will twist individually to accelerate, squeeze to brake, and glide up and down to steer. Unfortunately, for enthusiasts, the complete reliance on by-wire technology will probably ensure an end to feedback from the road to the driver; but on the bright side, this control unit is completely mobile, and the technology is reliable – by-wire controls have been used in jets for some time, and they are very reliable.







GM’s particular control unit can be positioned on either the left or the right side of the interior – thus an easy transition in driving on either side of the Atlantic (those boys back in Europe are sure to appreciate not having to pay $5 a gallon for petrol anymore; one hopes that hydrogen will prove to be a cheaper fuel).

O, and kids, please do not attempt relocating the driver control unit while operating this motor vehicle, leave that to the professionals. The lack of foot pedals also offers greatly increased driver comfort – there is now a completely free and open foot well (also thanks to the lack of a transmission tunnel – the electric motor and planetary gear are contained underneath everyone). Drivers can now almost consider themselves to be driving in an eternal state of cruise control (again, kids, please do not driver with your feet on the dashboard, your neighbor’s seat, or out the window, just because your feet are free).


All of this technology, except the driver control unit itself, is contained within what GM calls “skateboard chassis.” That means that the fuel tanks, the fuel cells, and the electric motor are contained within a 171.5- by 65.7- by 11-inch frame. Then, while I would prefer to yell “cowabunga, dude!” while holding the driver control unit and driving in my skating position (for about 5 seconds, before I get blown off or I fall off because I never learned how to skateboard) General Motors has graciously provided a body to cover the occupants. The by- wire technology connects to the chassis at one port, and the body and chassis share 10 mechanical connections.

This easy connection scheme allows for a variety of different styles to be easily implemented. Ford’s Model U concept employed a similar idea, by having many interior slots to make the vehicle easy to change, rearrange and upgrade. But GM’s Hy-wire goes way beyond this by allowing for a completely different body style to be easily attached. Except for the performance limitations of the Hy-wire’s fuel cell stack and electric motor, GM could just swap bodies and market this car to almost anyone – many different age groups, people from different areas of the country and world, and those of different socio-economic status. Obviously they would have to offer more options to make it a luxury vehicle, but it is easy to see the vast implications of this versatile layout.

As is, the Hy-wire concept has a body designed to highlight the vast interior space afforded by the lack of pedals and the lack of any major components being located outside its skateboard chassis. The front is mostly glass, to show off the lack of pedals (and give onlookers a great view of the driver’s feet) and the large empty space where most vehicles would have an internal combustion engine. Large windows are located all around, to give the up to 5 occupants an awesome panoramic view of the world outside. There is no “B” pillar, and GM paired this void with suicide doors on both sides of the Hy-wire, to allow it to open up fully to the outside world. So you can jump through the car superman-style if you so please. Cool stuff. Fighter jet technology, a body that rides on a skateboard and is as easy to put on as the body of a toy car, and an engine that doesn’t produce any pollutants. Forget that it produces little power; it still has enough torque to get you happily around town and out of the way of big-rigs on the freeway. There is an immensity of interior space due to the removal of the engine, the rest of the drivetrain and all controls from the volume of space occupied by passengers. The driver can sit in any position he or she wishes, as long as their hands can reach the driver control unit, a fact which should make long driving stints much more comfortable. Drivers can even switch sides halfway through the trip so they can lean their other arm on the windowsill. And, again, zero emissions! That’s just what we’re looking for today, so we can still live in the city and breathe without oxygen masks, and actually see rather than wading through a sea of smog. If GM makes this car affordable, and if someone can produce a reliably cheap source of hydrogen, then, ladies and gentlemen, we have ourselves viable solution to the need for personal transportation and a cleaner environment.

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