Years ago, I delivered a load of concrete to a crew pouring curbs at a strip mall in Boise, Idaho, with a rear-discharge mixer. After positioning the truck and helping the regular driver, Bill, hang a couple of chute extensions, I put the transmission in Low and watched in the right-side mirror as the foreman hand-signaled me to move ahead, stop, and increase or slow the pour rate. Bill also peered in the mirror and interpreted, but from the passenger seat he couldn’t see it all and besides, “Every guy has his own set of signals,” he explained later. The foreman was puzzled because too often I didn’t respond correctly, and he finally threw up his hands and grimaced—the universal sign of frustration. Bill saw that and said politely, “Here, I’d better take over.”
Now, if that truck had been set up for remote-control operation and I had been wearing the special box you see here, I’d have been back where the work was, operating the truck, barrel and chute, putting the concrete right where it was supposed to go and at the right rate for the crew to handle. That’s the purpose of the new Kimble Mixer K2200-RC, installed on the company’s current rear-discharge body and a Freightliner 114SD chassis, which I tried out recently at the company’s plant in New Philadelphia, Ohio.
Photos: Construction Equipment
Chet Randolph, an electrical engineer who had a big hand in the product’s development, was my guide for this demonstration, and he sat in the passenger seat as I drove the truck out toward the plant gate. I commented that the truck’s steering was rather stiff, almost as though it was non-powered. “That’s our equipment on the steering shaft,” he said, and the truck’s power steering had to overcome it. “We’re working on that and it’ll be corrected.”
I drove to a turn-around area just outside the plant gate and parked the truck. Randolph activated the RC controls on a box between the seats, and we climbed out. He hung the box around his neck, stepped back, and began running things. The truck moved forward and backward and left and right as he manipulated one of two joysticks. It’ll move as fast as 3.5 mph, he said. With the other joystick, he operated the drum in charge and discharge modes, and at various speeds. He also moved the chute, side to side and up and down. All of this duplicated what the driver would do from the cab and what a contractor’s crew member on the ground would do with the chute.
The parking brake is on while the driver is out with the box, and ordering the truck to move temporarily releases the spring brakes, similar to a work brake on a trash collection truck. They reset when the operator releases the joystick. “You have to keep a thumb on one of the dead-man buttons on the joysticks,” he said. “If you let go, everything stops. There’s also a gyroscope inside the box. If it’s dropped,” like when the operator falls down, “it knows it isn’t level and also stops things.” So there’s a double fail-safe. It’s conceivable that the truck could hit something while moving forward, so the operator simply needs to position himself to see what’s up ahead. The next generation RC may include a camera on the front of the truck and a screen in an enlarged control box.
Then it was my turn. I hung the remote control box around my neck and let it rest against my belly. The near side of the box is concave shaped so it fits comfortably. I stood within 20 or so feet of the truck while keeping an eye on any obstacles out front. Manipulating the joysticks, I moved the truck and chute pretty much where I wanted them to be. I found the remote steering somewhat touchy, as the front wheels cut quickly until I learned to gently push the joystick left or right. Moving the joystick up or down sent the truck rolling forward or rearward. Engine revs rose and fell as the truck sped up, slowed down or stopped, as though the diesel were directly propelling the truck, but it wasn’t. Working through a PTO, it was spinning a hydraulic pump that powered a motor on the transfer case and others on the steering shaft, chute and drum, as needed. I felt I was mastering the controls pretty quickly, but certainly needed more practice.
“We find they usually get the hang of it in about an hour,” Jonathon Randall, Kimble’s vice president of sales and marketing, said of people new to the device. He had arranged my visit and was amused at the fun I was having. Of course, the RC product is not about fun but efficiency and safety. It’s also about customer service, said Jeremy Sloan, vice president of operations at Ohio Ready Mix, the first buyer of the K2200-RC.
“We’ve talked to some of our contractors about it, and they are excited,” Sloan said, because they can eliminate one man from a pouring crew and offloading should go faster. And, “Once we get on the job site, we can get out and maneuver the truck with more eyes on where it’s going. That relates to safety.” He feels a rear-discharge mixer has a basic safety advantage because it backs onto the site and, when concrete placing and cleanup are done, it pulls straight out and onto the road. Front-discharge mixers drive onto a site, then often have to back out onto the road.
Sloan said an RC truck should move around a job site more safely and expeditiously because the driver will have a better view of where his truck’s going. And it will eliminate communications problems between the driver and the chute man or foreman. As for pouring, “We feel we can have the same advantages of a front-discharge but at less cost, which will put us at a competitive advantage,” he said.
List price for the RC is $29,500, said Randall. That, added to the price of a regular rear-discharge mixer, puts it about halfway to the relatively high price of a front-discharge mixer truck. Of course, all prices are negotiable, he added. Kimble’s RC product is currently available with a new K2200 body, which Kimble installs on most truck builders’ vocational chassis. And the RC is retrofittable onto existing K2200s. Eventually it might be adapted to older bodies and perhaps competitors’ products, but that hasn’t yet been determined. Five other fleets have also ordered the Kimble 2200-RC.
Sloan has ordered eight RC-equipped Kimble Mixer trucks, all on Freightliner 114SD chassis, and he plans to retrofit RCs onto five more. Ohio Ready Mix, based at Huntsville, northwest of Columbus, was a Sterling Truck fleet until the Great Recession, when Daimler canceled the Sterling program. Meanwhile, the company didn’t buy any new equipment for seven years until the economy revived, when it resumed by purchasing Freightliners. Sloan has been pleased with the trucks and their Detroit DD13 diesels, as well as the Allison 4000-series automatic transmissions that have become a regular spec for him.
“The new generation of drivers doesn’t know about manuals, and we were blowing clutches and a few U-joints,” he said. “The Allisons are so much easier to drive. When they’re moving around on a site, trying to take directions from a crew—move up, move back—now they’ve got one less thing to worry about. And now we can accelerate quicker and get to the job site faster. And we’re saving fuel. I don’t have any solid numbers yet, but last year we probably saved $10,000 in fuel. They’re rock-solid. We’re having no problems at all with the Allisons.”
As for the Kimble RCs, the fleet has 24 trucks, and “our goal in three years is to have all our trucks with remote control,” Sloan said. “I’ve watched it work and have 100 percent confidence in it.”
