The company previewed its new Hitachi Solution Linkage Integrated Grade Control with Topcon at ConExpo 2020. The system, designed so operators can set and hold grade while digging, comes a year after Hitachi released its 2D and 3D guidance systems.
Jonny Spendlove, excavators product marketing manager for Hitachi Construction Machinery – Americas, says that with the machine control technology the operator controls the arm, while the machine automatically controls the boom and the bucket.
The system prevents over-digging and allows the operator to set “virtual fences” around the excavator to prevent the machine from extending beyond boundaries for height, depth, front, swing and reach.
“You can set a perimeter or a boundary where you don’t want your boom to pass or you don’t want your machine to pass,” he explains. “You can do that on the sides. You can also set a virtual ceiling, if you’re working under power lines. You can set a virtual floor so that you don’t dig below a certain point.”
Spendlove sees the 2D guidance as a good entry point for those wanting to reap some of the productivity benefits but are not ready to make the larger investment for machine control. 2D guidance doesn’t require a base station. It continuously checks the grade with a rotating laser to guide the operator, which eliminates the need for a worker in the trench to do the checking. The 3D guidance uses Global Navigation Satellite System (GNSS) to display the position and elevation of the bucket’s cutting edge.
“Our customers tell us that their productivity on just guidance is going up dramatically,” he says.
With the upcoming integrated control, the 2D system controls the elevation of the boom and bucket to the designated grade, while the 3D system controls the elevation and position of the boom and bucket by GNSS reference. For the 3D control, the modeling for the jobsite is uploaded to the touchscreen monitor by USB drive. Spendlove says the operator can make adjustments to the model via the touchscreen.
“When you go to control, you’re putting a Topcon valve essentially over the control valve of the machine,” Spendlove says. “So when you arm-in, your boom and bucket are going to be hydraulically controlled by the grade control system. That adds a lot of additional productivity, especially for newer operators.”
Features on the machine control include payload weigh with bucket sensors to let the operator know how much weight is being added to the truck as it is being filled. It also provides a variety of tabulations, such as weight loaded by truck and by the day. The data is integrated into Hitachi’s ZXLink telematics. It also transfers data wirelessly and allows remote display access.
The sensors for the control system, or inertial measurement units, are on the excavator’s arm and boom and are protected. GNSS receivers for 3D control are also installed on the excavator.
“One of the benefits of having this integrated from the factory relative to aftermarket is it’s calibrated from the factory,” Spendlove says, so it’s ready to work when delivered. “It also meets our specs for durability and reliability. … We want to make sure it’s totally protected.”
Spendlove says the Hitachi excavators integrated with machine control will maintain the same feel for operators as its excavators without grade control. There are no changes to the hydraulic system.
“We want to maintain those pilot controls, because we think there’s a lot of benefit in terms of controllability,” he says. “… We don’t sacrifice the smoothness of the controls.”
The new integrated 2D and 3D control systems will be available as an option on ZX210-6, ZX210LC-6 and ZX350LC-6 excavators later this year, with additional Dash-6 models available for the option in the future, Spendlove says.