The headline and most apparent feature of John Deere’s SmartGrade machine control for motor graders is what the system doesn’t have: masts.
Launched in August 2018, the mastless grade control system is the first of its kind on graders and removes expensive equipment from extremely vulnerable positions on the machine while also eliminating a considerable daily chore for operators in mounting and calibrating the equipment, before having to remove it all once it’s time to call it a day.
But what truly sets the system apart is its accuracy and its grader-centric design.
Luke Kurth, marketing manager for Deere motor graders, says SmartGrade’s accuracy on graders comes from in-cylinder position sensing. You can check out the video or read on for all the details.
Kurth says that inside each of the grader’s hydraulic blade cylinders is another rod with a magnet on the end. As the cylinder extends out, a sensor inside sends a pulse down the rod that bounces off the magnet and comes back.
Using the time it takes for that signal to return, the system can sense how far the cylinder is extended. Kurth says knowing that allows the system to determine the position of the blade within a millimeter.
”And because we know where [the blade is] within a millimeter, where the other lift is, where the circle side shift, where the blade side shift, where the blade pitch is, we can put this machine in any position we want and hold those ultra tight tolerances,” he explains.
Kurth adds that it’s a method of position detection that can’t be done via an inertial measurement unit, a sensor that has become a staple in machine control for dozers and excavators.
“An inertial measurement system requires movement and requires you to always move the blade around and make adjustments on it,” he says. “For a motor grader, you typically don’t run it like that. You typically shift the blade out, you put it in a position you want and leave it there.”
Kurth says the in-cylinder position sensing allows for positioning that is tailor-made for motor grader operation.
Despite all the excitement around SmartGrade and the GP (GradePro) grader models it comes factory installed on, Kurth was adamant that Deere is not trying to push customers into buying the new integrated system.
”We didn’t get rid of anything. We don’t want to dictate to customers what they should have and what they shouldn’t have,” he says. “So all the solutions that have been available for John Deere graders are still available.”
In fact, even on the SmartGrade GP machines, you’ll still find mold board mounts for masts and coil cable hookups. That’s because Deere is manufacturing each grader to be very flexible when it comes to a customer’s preference of machine control. All Deere graders also support sonic systems for times when GPS connectivity is weak.