A little over a year ago, we introduced the Topcon X63i excavator system to the Australian Market. Unlike the X63 system, which continues in parallel, the X63i is designed specifically for excavators – and is cheaper!
The reason for this is that an excavator GPS system is used for guidance rather than machine control, so there is no need to hook into the hydraulic system – saving around $20k in system cost. A further upside is that being significantly more compact, the X63i can often be integrated into the excavator whereas the bulkier machine control systems are generally removed from a machine at night.
The downside is that the system can only be used on other excavators or indicate machines: the X63 system is needed if there is a requirement to share with automatic machines like dozers and graders.
Joel Seddon, Position Partners’ National Product Manager – Machine Control, recently spoke to Earthmover and Civil Contractor about what can and can’t be done with a machine control system on an excavator.
Setting up for buckets
Excavators generally operate with a range of buckets, and a machine control system can readily cater for this. It is a simple 10 to 15 minute process to calibrate the system for a particular bucket and enter its identifier into the system.
Joel says that owners will generally mark some form of hard code on a bucket that matches the identifier in the system. Paint is not as widely used because it can wear off.
Tilt buckets and tilt hitches can be catered for with an extra sensor for the degree of tilt. While rotating hitches are not yet catered for, Joel notes that this is currently being researched although he believes that a solution is probably a couple of years away from market release.
Excavators with offset booms can be catered for, as can excavators with three part booms (much more common in Europe).
For fleets of excavators e.g. hire fleets, systems are generally shared between machines as not every project requires a guidance system. Joel states that a machine likely to be used with a GPS can be fitted with a basic set-up for around 12-15% of the cost of a full system, with the GPS components swapped in and out as required.
Not just buckets
The range of attachments used on excavators goes well beyond buckets, and these can generally be catered for. Applications include hammers, rock grinders, augers, rippers and the like. The means of doing this can involve “tricking” the system with a bucket width and depth that matches the attachment.
The system has application not just when digging but also when surveying work during and after construction using a point mapping feature. This means that excavation progress can be measured and ultimately an “as built” record can be provided.
This is particularly useful for batters, underwater excavation and other areas that are difficult to access safely for conventional surveys.
Regardless of the bucket or attachment being used on an excavator, a machine control system provides the potential for significant productivity improvements.
Having an accurate grade to work to (without requiring regular surveyor checks) allows faster excavation and improves confidence in the finished result.
Avoiding over-excavation not only eliminates unproductive time but can also reduce the cost of fill materials (concrete, base materials, etc.) placed in the excavated space because actual volumes are close to design.
There are significant advantages with “blind” work because the machine control screen provides a set of “eyes”.
Machine control is also a significant advantage when excavators are working in layers.
A further potential advantage is using telematics to update designs where changes are made. It not only speeds the process of updating designs but ensures that everyone is working to the current design.
This compares favourably with surveying, where work stops until a surveyor sets out new pegs; and with early generations of machine guidance where the surveyor had to locate each machine, stop it and upload the new design.
Joel believes that the volume of earth moved justifies investment in machine guidance for excavators of 12-15 tonnes operating weight and upwards. However it has been used successfully in much smaller excavators in applications such as detailing in confined spaces where accuracy is important; or working on golf courses and sporting fields, where the low ground bearing pressure of a lighter machine is required as well as a high degree of accuracy on levels.
Article written by Greg Keane, Editor at the Earthmover and Civil Contractor magazine.