If you invent technology for trains, you spend a lot of time on test tracks waiting for something to happen. And so it was, about five years ago, that Ajith Kumar found himself pondering a problem: how could he partially lift the multi-ton middle axle of a diesel-electric locomotive and give it better pulling power on a wet track?
GE Transportation’s Super Tugger tows an assembled truck of an Evolution Series locomotive. Kumar holds 200 patents, including patents covering axles in such trucks.
Invetor Ajith Kumar atop a GE Evolution Series locomotive.
Then a train came into view and started braking. Standing amid the screeching and noise, Kumar saw up close how a compressed air cylinder applied the friction brakes. “I thought, if you can use it to apply that kind of force on the wheel, surely it could lift the axle,” Kumar recalled.
Armed with this insight, Kumar, a GE consulting engineer, went into his office and filed a patent, which is something that happens to him a lot. In the 36 years he has worked at GE Transportation in Erie, he’s had 200 other Eureka moments – big and small, in his car and at the supermarket – that led to patents. (“I don’t know where it comes from,” he laughs. “But it’s not generally at work.) He lags behind Thomas Edison’s 1,093 U.S. patents but the number puts him on par with the GE’s most prolific modern innovators.
Many of Kumar’s patents are individual but others are shared with colleagues. “Just an idea won’t do the job. You have to have people work on it, too,” Kumar said. “You have to have the implementation and that involves a lot of teamwork.”
Kumar’s drive to improve train technology was a surprise career choice. He joined GE in 1977 from Stanford University, where he studied digital controls. He soon filed his first patent for reducing the current on a transmission line but getting the same amount of power. “The first few are exciting,” he said of his patents.
Some of his greatest achievements came in pursuit of technology that hasn’t yet materialized. Take the hybrid locomotive, which would combine a diesel engine with batteries that capture waste energy from braking – a sort of Prius on rails. “A braking locomotive puts out a lot of kilowatts. Almost a small town could use that,” Kumar said.
Storing that power requires batteries that last 20 years, add only a bit of cost to the vehicle, survive intense vibration and endure temperatures greater than the boiling point of water. Kumar had an idea.
Kumar and his team always start by reviewing and experimenting with existing technology, then seeing what else they can do. Eventually the team hit on metal halides, a material that would be solid and inactive at room temperature but, when melted, becomes a battery. The technology has evolved to become the Durathon battery, which stores as much energy as other battery chemistries but takes up far less space. The Durathon does not yet serve on locomotives, but telecoms use it for backup power and wind farms store excess energy in the batteries.
Another innovation that grew out of the hybrid locomotive project was the Trip Optimizer, a software and big data system that tells a locomotive when to brake and apply power in anticipation of hills and curves in the track. The platform helps trains improve efficiency and save large quantities of fuel. It was another idea that took an unexpected turn and yielded great things.
“We don’t have a hybrid locomotive today but we have two new products, Trip Optimizer and the battery, which hundreds of people work on. So you have no idea where it’s going to go.”