On the road with Sunsetters
A Day In The Life of
The Super Star Solar Car Driver
Sunday, July 22
by Luke Graunke and Jason Gates
We're usually up by 5:30 to assist with setting up the array for morning charging and eating breakfast. Before the first driver starts in the morning there are a few things that need to be checked. We have to check the voltage in the accessory battery, which is used to power the telemetry system that sends important power use information to the chase vehicle; that way the chase vehicle can monitor how well we are driving. We also fill up a camel back every morning that way we have plenty of fluids to drink while we are racing through the hot desert. Each driver also has a ballast that they must place in the car while they are driving. This ballast makes sure that every driver is brought up to a weight of 80kg roughly 176lbs.
Through the 10-hour race day there will be two driver changes completed so that each driver is in the car for no more than 4 hours at once. Being in the solar car for that long of a period of time requires that the driver is somewhat comfortable during his or her shift. To accomplish this they wear water socks rather then tennis shoes. This allows them more movement while they are in the car because the water socks form a tighter fit over the driver's feet. They also make sure to wear shorts and a white t-shirt. This helps them to stay cool when they travel. Another key thing they do every morning is a to put their helmet on and do a radio check. The drivers need to be able to communicate with the lead and chase vehicles so they can be informed of how well they are driving, up coming road hazards, and route directions. When it is finally time to start the racing day the driver crawls into the car and another team member assists with buckling the 5-point harness and connecting communication wires. Once all of this is taken care of the driver tries to adjust to his awkward driving position. The car is driven from a laying down position. With the exception of the lying down position in the car, and not having air conditioning, the car is similar to most other vehicles; the driver has a brake pedal, gas pedal, steering wheel, horn, blinkers, and brake lights. A few unique characteristics of the driver's controls are driving with both feet, one on the brake and one on the gas and the use of regenerative braking, which sends power back to the batteries when slowing down. The solar car handles a little better then most vehicles because it is wider and lower to the ground. You are able to turn quickly at fast speeds; the reaction of the car is more similar to a go-kart then a typical car. The acceleration is adequate to keep up with traffic but to conserve energy during the race we have to accelerate slowly. The brakes are hydraulic, like a car, and can stop the car quickly in case of an emergency. Typically when slowing for a turn or stop sign the regenerative braking is used to conserve energy.
The overall ride experience is quite different than a regular vehicle. The driver is very low to the ground when he drives so it feels like you are going 55mph when you are actually driving 40mph. To save energy the tires on the car are inflated to 105 psi which causes the car to ride very rough. When you are driving you feel every bump and when the lead vehicle warns of a bump ahead the car must slow down to avoid damaging any of the suspension components. The car drivers must also pay attention to any strange noises or any pulling in the steering wheel, which might indicate a flat tire. One aspect of driving the car that can be a discomfort is the heat. When you are driving the car the temperature inside is usually 10 or 15 degrees hotter then it is outside. This heat causes the drivers to sweat profusely and also causes concern with issues of heat exhaustion or heat stroke..
After a driver's shift is over the driver is both mentally and physically exhausted. They have spent the past 3 hours concentrating on the road and enduring awkward driving positions and extreme heat. Even though driving the solar car is such a demanding task it is definitely worth it!