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Construction Equipment for the Future and with a Future

Our Machine Control Technologies

The challenge of machine control is to make blindfolded machines perform the skills of veteran operators who can operate bulldozers while looking at work conditions and predicting work ahead.This challenge is also a driving motivation for engineers.
Takahiro Shimojo
Manager, ICT Development Group,
Construction Equipment Technical Center 1,
Development Division
Takahiro Shimojo, Team Leader, ICT-Intensive Construction Equipment Development Group, Construction Equipment Technical Center 1, Development Division

It is said that bulldozers are more difficult to operate than various other construction equipment. While bulldozers are constantly in vibration, with rolls and pitches, operators need to move them at appropriate speeds as they control the heights and angles of the blade. The way they initiate a cut by positioning the blade on earth also affects construction efficiency. When the volume of earth being pushed increases, bulldozers can slip and damage the surface. To avoid overloading, they need to raise the blade and gradually level the ground. They also need to evaluate soil conditions and ground formations, and then engage in a series of complex operations without being able to look at the blade on the surface. Therefore, it is said that it usually takes three years of experience before they feel competent to operate bulldozers.

Machine Control automatically manipulates the blade for the operator. Mainstream Machine Control bulldozers today are not equipped with functions to detect blade load and track slips. Therefore, they can fully demonstrate Machine Control capabilities only in finish grading. In terms of the expected volume of work starting with rough dozing, only 10%to 20% is automated. Our D61EXi/PXi-23 models are equipped with the worldís first full blade control technologies from rough dozing to finish grading. Therefore, operators are required just to move them forward and backward, leaving all other tasks to our machines, such as rough dozing by automatically controlling the blade to avoid track slips, and high-precision finish grading by automatically shifting to this mode when the machines approach the design surface. We have achieved this fully automatic control by becoming able to detect blade load and track slip information. At the same time, by making the GNSS antenna built into the operator cab rooftop, we have eliminated the problems of cutting the cable and damaging the antenna after getting hit by hard objects as well as of daily mounting and dismounting tasks for the antenna.

It was very challenging for us to recreate the blade control performance of veteran operators by applying ICT. When the body of D61 models moves up and down by one degree, the position of their blade edge changes by 70 mm. Veteran operators control the blade appropriately, as they predict coming changes by using their vision and sensing their body movements. We have recreated blade control comparable to that of veteran operators by tuning more than 20 parameters which combined the iMU+ sensor responsible for recognizing body positions and the MS Mechatro Smart Cylinder capable of detecting cylinder strokes. This tuning process alone took us one year, working very closely with our Test Engineering Center to repeat many experiments.

We conducted seeding activities in cooperation with customers for our Machine Control models in the United States, a major market for medium-sized bulldozers. Seeding activities provided valuable opportunities for me to not only refine machine performance but also learn about how our machines are being used by customers from a development engineerís viewpoint. For example, I had no idea in Japan that medium-sized bulldozers are used on slope construction. The slope was nothing special when I looked at it, but it required extraordinary efforts of all involved in seeding activities to ensure accurate real-time recognition of machine positions and directions by using the 3D GNSS and iMU+ data for perfect sloping work.

Although D61EXi/PXi-23 models are now in commercial production, I think my next task as a development engineer calls for improvement of customersí jobsites in the entire construction process, from preconstruction to final survey upon completion. We must improve not only the performance of one bulldozer but also customersí productivity as a whole. In this way, we will be able to make significant contributions to them. I am now looking into this possibility.

The more ICT intensive or automated construction equipment becomes, the higher the performance and precision will be expected from key components, such as hydraulic cylinders.
Masato Kageyama
Team Manager, Control Equipment Development Group,
Hydraulic Equipment Technical Center,
Development Division
Masato Kageyama Team Leader, Control Equipment Development Group, Hydraulic Equipment Technical Center, Development Division

The Hydraulic Equipment Technical Center plays an indispensable role in Komatsuís commitment to in-house development and production of key components, and I feel that our Center has a particularly strong climate of creating things by ourselves, if we cannot find them available anywhere. One such example is our original MS (Mechatro Smart) Cylinder, featuring in-house developed sensors, which incorporates our electric control technologies, that have been accumulated over 20 years, and our sensor technologies that have been refined over about 10 years for hydraulic equipment. As MS cylinders are installed in construction machines, they are expected to generate big power under rough conditions. Furthermore, there are about 10 meters separating the base of their boom and their bucket, but they are required to move the bucket precisely, calling for the need for smaller than millimeter, super-precision measurement of cylinder strokes.

Before we began development, we first decided that we would never damage the durability and reliability of cylinders, which were proven over the years, by adopting sensors. We also wanted trouble-free applications to other models in the future. To this end, we decided to develop add-on sensors from the very start, without changing the basic structure of cylinders. Development of novel sensors definitely brought about continuous challenges to us.

For example, when you install a piece of magnet inside the cylinder tube made of steel which shuts out magnetism, and install a magnetism-detecting sensor, theoretically speaking, itís totally impractical. Encouraged by our supervisor, saying "Everything we have in this world has been made by those who truly believed they could make it. When you think you canít, you just canít", we repeated the production and simulation of trial sensors. One day, we discovered that we were able to detect a very small amount of magnetism which came through the steel tube, when certain conditions and shape were met.

Although we were able to detect magnetism, it turned out to be useless due to poor measurement. We faced a continuous series of new challenges, such as the fact that magnetism doesnít travel at the speed of light within magnetized material and the need to consider and evaluate even slight delays caused by very weak electricity generated within magnetized material.

In addition to developing technologies to make sensors more compact and higher in precision, we also needed to plan and develop original bench test equipment for cylinders by considering all possible conditions of machine use, and calibration, inspection and other equipment for mass production of sensors. It has taken 10 years of dedicated effort from more than 20 engineers on a cumulative basis, who were committed to components of ever higher performance and precision.

I would like to develop this model together with customers, as each and every one of us at Komatsu fully demonstrates individual talents and teams up, which is our corporate climate.
Kiwa Nishimura
Chief Engineer, Hydraulic Excavator Development Group,
Construction Equipment Technical Center 1,
Development Division
Kiwa Nishimura, Chief Engineer(?), Hydraulic Excavator Development Group, Construction Equipment Technical Center 1, Development Division

Today, we are involved in the development of the second model of Komatsuís ICT-intensive equipment, i.e., a hydraulic excavator with Machine Guidance functions. Compared to other construction equipment, hydraulic excavators perform complicated movements. For that reason alone, automation is very challenging, so we have decided to launch this model initially, in which operators are required to operate manually but which offers information needed for their operation. This model is in the final test stage, which assumes actual jobsite operations, and is just around the corner for commercial production.

Like automotive navigation systems, Machine Guidance is designed to alleviate the operatorsí burden and improve the precision and efficiency of their work. To this end, we needed to enhance the method of displaying real-time surface landforms and operational navigation to the design surface, so we decided to enlarge the size of the display monitor. However, a large monitor can obstruct the operatorís view and increase the risk of becoming defective resulting from vibrations due to its heavy weight. We thoroughly studied the location of a large monitor at the Cab Development Center, conducted durability tests at the ICT Development Center and made considerable modifications to the monitor. We also added the assistance function by beeping sounds as the bucket teeth approach the design surface.

Unlike the conventional development of mechanism-oriented products, the development of ICT-intensive products called for more orientation on applications, which meant designing the monitor in consideration of how the machine is going to be used. Our development project began in 2009 by getting not only development and production people involved, but also product support people who are very familiar with how the machine is used by customers as well as people of ICT device makers at start-up. It was a challenge by one group of people with different expertise. It was also the first experience for me to collaborate with people routinely working at different sites in Japan and abroad, and I have reconfirmed the importance of sharing information and communications.

Play Video

Komatsu demonstrated a pilot model of the Machine Control hydraulic excavator with fully automatic excavation functions at the Bauma trade fair in April 2003.
Reference: While the operator kept his hand away from the lever, the bucket was automatically moving to shape the design surface.

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