If any dynamic felt out of phase while driving the Chevrolet Sequel fuel-cell, there was consolation knowing it could be corrected to my, or anyone else's, exact preferences with a few simple keystrokes.
Brakes feel a little mushy. The engineer in the back seat picks up the computer keyboard. Click-tap-tap-tap-tap-ENTER. Damn! Now they're as firm as a cement truck.
These are the benefits of by-wire controls. Throttle, brakes and steering are all controlled electronically. There are no direct mechanical and/or hydraulic links between the driver and the power modulator, steering rack or brake caliper. Every adjustment for driver interface is programmable, adjustable within a desired range and repeatable.
The by-wire system became more feasible with the hydrogen fuel-cell power train. A 42-volt architecture is needed to power the controls, and considering the fuel-cell stack gives off over 300, then borrowing a volts isn't a problem.
The Sequel is powered by a 65kW main motor that drives the front wheels and a pair of 25kW wheel-hub motors in the rear. Together they motivate the 4,774-pound Sequel (plus four occupants) with poise and competence, not necessarily blinding authority, from a standing start. I would have preferred more confident acceleration for passing speeds, but the overall performance matches similar-sized vehicles in the crossover segment.
There is one advantage to the weight, especially when most of it under the floorboard. This vehicle feels like it's glued to the road. Body roll was minimal yet the ride was compliant over road imperfections. All four shock absorbers, of course, were electronically controlled.
Steering is both a joy and annoyance in the first drive. At slow speed the steering ratio is as fast as a World of Outlaws sprint car. Just turn the wheel a little and the response is immediate and substantial. The Sequel also has rear steering to facilitate tight parking and U-turns. At highway speeds the steering ratio slows up considerably for relaxed cruising. I prefer a little quicker steering on the highway and didn't feel the transition between slow and fast speeds was very predictable. I didn't mention it during the test drive but had I complained: Click-tap-tap-tap-tap-ENTER.
The first question always: is it safe? Yes. As someone who is a huge fan of the GM QuadraSteer system that briefly was available on Chevy and GMC trucks, I know that there are numerous backup safeguards built into electronically controlled steering systems. As an added security measure for this test drive, engineers had a direct link to the steering rack from the steering wheel, but it could only be engaged with a clutch if the power went out. Engineers are confident that such measures will not be needed in production version.
Getting used to the electric motor whine may take time. Think of a small Roots supercharger on an engine that is never shifted and winds to 15,000 rpm. Also, the whooshing noise from the exhaust needs a manly note. It sounds like a clothes dryer exhaust vent.
This is my second drive in a hydrogen vehicle and both were held under very strict and controlled supervision. I want to be a hydrogen test dummy and log a month or two on the road under different road conditions. I guess I have seen the future and know the potential. I'm hooked.
Next: A closer look at the by-wire technology and driver interface
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