First You Make It, Then You Try to Break It

For the past six months, the research and development lab, located in a wing of Heil's Fort Payne, Ala., manufacturing plant, has been flexing a Python's muscles.

Heil's latest product, the Python, aims to improve the performance characteristics of automatic container lifts. According to the company, the Python starts its cycle with a slow, even movement. Once in motion, it accelerates to warp speed. Just before reaching full extension, it decelerates smoothly, grabs the container gently and slowly begins the journey back to the truck, Heil says. Once again, after a slow, even first move, the assembly accelerates rapidly to full speed. Upon reaching the truck, the Python slows to a comfortable pace, dumps its load, gently reverses direction for the return half of the cycle, accelerates to full speed, slows down to release the container and flies back to the truck.

Despite all the speeding up and slowing down, the Python does its job in 8 seconds, Heil's standard for automatic residential lift operation.

Why bother?

“It prevents the truck from rocking during the cycle,” says Kevin Coombes, director of customer services. Coombes claims that the process also extends the life of the lift “because it only runs fast in the middle of the cycle and accelerates at an even pace.” Finally, he says, the new product “causes less wear and tear on the carts.”

Heil designed the Python with a ProE CAD system capable of something called solid modeling. This is a 3-D design process that allows the construction of virtual machines inside a computer. “You can see the machine and even operate it virtually,” says Paul Talley, Heil's test lab supervisor. “When we get a virtual design to work, we make one with those specifications and test the real machine.”

Talley tortured the prototype Python for six months, running it through a million cycles, the equivalent of five years of operations. When it didn't break down, the company decided to produce it.

“An automated arm mounted on a truck has to act like a human arm,” Talley says. “It has to grab a 100 gallon container, empty it and put it down again. The trick is to make an arm that can do that without breaking or wearing out prematurely.”

Talley's goal is to find some way — within the operational rules of the trash collection task — to wear down the pivots, joints and hydraulic actuators that make up a lift arm. “The hydraulic cylinders on an automated arm are like the muscles in your arm,” Talley says. “They do most of the work and absorb most of the energy. So we put them under severe stresses to verify that they will hold up.”

Despite months, if not years, of testing the Python, Talley remains unsatisfied. He continues to test the device — with the literal goal of trying to break it.

So far, he's failed. And that makes him happy.

Talley's lab spans 15,000 square feet and contains two 3,600-square-foot hydraulic testing pads and a 2,600-square-foot shop.

The equipment includes tube benders, flaring tools, welders, lathes, an upright milling machine — anything and everything necessary to building any kind of a machine.

Then there's the test equipment, which includes an environmental chamber as big as a refrigerator, computerized data collection equipment, devices for measuring the stresses and forces placed on test units, and on and on.

When Talley isn't studying the Python's arm movements, he spends his time trying to break one of the other Heil devices.

Recently, for example, he took a run at the programmable logic controller that provides computer-controlled operation for a variety of Heil trucks. Talley stuck the controller in the environmental chamber and tried to freeze it to death by turning the temperature to 40 degrees below zero.

It continued to function.

Next, Talley cranked the temperature up to 165 degrees above zero. The controller didn't even break a sweat. “It performs very well under these kinds of conditions,” Talley says in an even voice, which makes it difficult to tell whether he's happy or sad that he hasn't broken anything for a while.

According to Mark Keller, Heil's director of engineering, the lab cost several million dollars to assemble. The goal of the lab is to contribute to Heil's overall research and development efforts. “We have three goals in R&D,” Keller says. “First, we want to make our products bulletproof, so they just don't break. Second, we work to make our products perform better. Third, we try to develop new products that will lead the market.”

To these ends, the R&D lab's current projects are focused on developing more ergonomic controls, adapting additional truck models to the operating gear hydraulic system and designing new arms for semi-trailer collection operations.

“A big thrust of our work right now involves improving ergonomics for drivers of automated trucks,” Keller says. “The driver in the cab of a front or side loader has to operate a number of levers and controls to move the lift arms, and we're looking for ways to make these controls more easily accessible and easier to operate, with minimal motions.”

Keller's development projects also include improving a system that has been on the market since fall 2000: a hydraulic assembly that the truck can operate productively while idling. “We started working on this project to reduce truck noise during early morning collections,” Keller says. “What we've developed operates very quietly and even has produced the additional benefit of increased fuel economy. The system now is available on our automated side loaders, and we're working on systems for our front loaders and rear loaders.”

As Heil engineers round this and other new concepts into shape, Talley ponders ways to test their new designs, and maybe even to break them.