Earth control: moving earth productivly and accurately

Technological advances in machine control systems as well as operator controls have in part been introduced to combat the problems the industry is currently facing with the shortage of skilled operators. This fact led Caterpillar to rethink the way its graders (one of the most difficult machines to operate) are controlled by the operator. In Caterpillar's new M Series of graders the steering wheel and up to 15 levers traditionally used to control these machines have been replaced with two joysticks.

Pierre-Nicolas Selenne, road construction supervisor for Caterpillar in Europe, Africa and the Middle East (EAME), said, “We decided to make the machine as easy to operate as possible and more intuitive so that the operator would be much more comfortable and more productive.”

Mr Selenne added by removing the levers in the cab, visibility has also been increased and therefore safety is improved. Also, he said training operators to use the graders is quicker and with the addition of Cat's grader control simulator it takes just a few hours for the operator to become comfortable with the system and a few days to become intuitive with the machine.

Traditional methods

Meanwhile, Terex's new TG motor graders feature traditional lever controls rather than joy-sticks. Brian Heathcote, vice president engineering for Terex, said joystick controls are still yet to be widely accepted by the company's customers.

He added, “While standardised controls would normally enable operators to transfer to other products with ease, the grader is a complex product to operate, regardless of operator interface. This, combined with the limited numbers of highly skilled Terex grader operators, prompted us to offer the industry ‘norm' in terms of controls. This is a decision we will review and monitor over time.”

Brian Lowe, product manager for graders at Volvo CE said, “Operators are familiar with the set pattern and location of controls, which is an important factor when deciding what layout is most user-friendly for the people who actually control these machines. Obviously there will always be a certain bedding-in period when an experienced operator gets acquainted with a new grader but the important point is to not introduce too many new technological improvements too fast.”

According to Volvo CE the familiar lever pattern and lever-to-steering-wheel relationship is considered a key element for both ease of operation and accuracy of the finished grade.

Developing technology

Rogier Tonies, machine control guidance specialist for Caterpillar said another new trend is the term ‘connected work site'.

He explained, “The connected worksite is a concept that brings all telemetric solutions together; thus combining Cat Product Link and Cat AccuGrade (machine control and guidance products) with future additional functionality to send project design files from the office to machine and back. This will allow a lot of new possibilities, for example, remotely and real-time monitoring of machine health or measuring the progress of a project and volume of material moved on a daily basis.”

AccuGrade combines digital design data, in-cab operator guidance features, and automatic blade controls. Caterpillar machines have five different systems offering varying levels and combinations of automatic cross-slope and elevation control.

Marilyn Murphy, Caterpillar's regional manager for productivity solutions, said, “Caterpillar believes that this technology will be standard in the very near future. As we want to be there for our customers, now and into the distant future, we've embraced the technology, integrated it into our products and even more importantly integrated it into our worldwide dealer network.”

Meanwhile, JCB offers the Spacetrac system – a fully integrated satellite monitoring and diagnostic system which is available as an option on the larger of the company's new wheeled loaders.

A spokesman for the company said, “This system enables a JCB engineer to connect to the loader from any PC via the internet. Once connected, the engineer can access any servicing and repair requirements as well as being able to pinpoint the precise location of the vehicle.”

JCB's wheeled loaders extend from compact models such as the JCB 406 through to the larger 456, which offers up to 19 tonne breakout forces.

New machines

Most of the new earthmoving machines introduced at the Bauma exhibition this year featured US Tier 3/EU Stage IIIA compliant engines due to increasingly stringent emissions regulations. All of the major manufacturers, including Caterpillar, Komatsu, Liebherr, JCB, Doosan, Hitachi, Terex, Volvo, Case, New Holland and Hyundai launched new excavators at the show. These companies also introduced a plethora of new wheeled loaders.

Most new dozers above the 10 to 11 tonne range are now compliant with Tier 3 engine emissions regulations and new to the market this year are Cat's D6K, D6T and the D6G Series 2XL and D7G Series 2 models. Komatsu's new 13-tonne D51EX/PX-22 dozer features a Tier 3 engine, which is quieter and more fuel efficient than its predecessor, according to the company. New Holland launched the 16 tonne class D150B dozer at Bauma featuring a Tier 3 engine and hydrostatic transmission.

Meanwhile, articulated dump trucks (ADTs) introduced this year include Cat's ejector version of the 30 ton (27.3 tonne) capacity 730 ADT and new from Bell is the B30D HP, an upgraded version of its 30 ton (27.3 tonne) capacity B30D. Bell also introduced the tracked version of the B30D, which is developed for use on peat soils.

New graders include Caterpillar's new, seven-model line-up of M-series motor graders including the 120M, 12M, 140M, 160M, 14M, 16M and 24M. Meanwhile, Volvo introduced its G990 series of motor graders this year and Terex introduced the 23 tonne TG230 model to its range of TG motor graders. John Deere's D-Series motor graders include the 670D, 672D, 770D and 772D models. They have been updated to include a mid-mount scarifier and an integrated grade control package.

Outlook

Machine control systems make life easier for the operator and help to improve productivity, accuracy and efficiency on the construction site. Changing the style of operator controls in earthmoving equipment, especially in graders, is currently a subject of debate for manufacturers. While some say replacing the steering wheel and levers with joysticks will help to attract and retain skilled operators, others say the change is not yet necessary.

Speaking about the trend towards integrated machine control systems, Mr Tonies said the next challenge for contractors is to find people who are skilled in jobsite data management.