Comment: Digital setting out
A workable solution for the Middle East?
Digital setting out technology is transferring BIM models (AutoCAD & Revit) electronically to the job site by using a Robotic Total Station (RTS) and tablet set up. This device is then used to locate your drawings specific location points such as hanger points, building works holes, equipment locations, lighting fixtures and pretty much anything that you can identify in the model.
This method of setting out has been widely adopted in the North American and Australian markets with hundreds of building sites taking full advantage of these labour saving tools.
The current method which exists in the Middle East is printing BIM models to a large A3 sheet of paper with hundreds of dimension lines on it to allow installers to then measure manually using tape measures and string line.
My entrance into the world of sales for the MEP market began in the western region of the United States back in 2008. My company at the time, TSI, was the sole provider of MAP’s CAD-Duct drawing platform (still one of the most commonly used programmes in the industry worldwide). Within months of my arrival TSI had partnered up with Trimble to provide the MEP industry with its first edition of the Trimble MEP Robotic Total Stations. The idea behind this was to create integration between 3D models and the job site.
Having sold CAD-Duct in this area I could instantly see the connection of taking all of my hanger point locations and placing them electronically into this system. Contractors were seeing labour savings within days of using the robot. A typical return on investment for this would be two installers manually setting out using tape measure equals 75-100 points. One installer using the Trimble robot equals a minimum 500 points in a day. These sort of numbers can have your robot paid for within a month of setting out. The industry had never seen this type of return on investment for a BIM tool.
Fast forward to today and I can see that thousands of Robotic Total Stations are being used for all types of setting out in the construction industry, but not the Middle East.
My departure from TSI in 2015 led me to Trimble MEP as it had hopes of bringing this technology to the world.
The first objection I was receiving here the Middle East was: ‘’We don’t draw support hangers”.
How can this be? I thought everyone was modeling hangers?
How can you provide a fully 3D coordinated model without including the most important part of the process?
These questions were running through my mind constantly during the first six months of my time at Trimble MEP.
Does this mean we need to pack up shop and move back the US? No.
Although I would like the Middle East to catch up with this process and fully meet the upcoming BIM expectations, Trimble MEP has been fully aware of contractors who don’t add hangers as part of their design deliverable. This is why it has created Trimble Field Points. A very easy solution to add point data in replacement to modelling real hangers.
After selling and training on this solution for over five years there hasn’t been any instance where we haven’t got the end user fully trained on the unit no matter the age or experience with computer technology. The unit has been made very easy to handle using the Trimble Field Link software.
With a small majority of companies that have been exposed to this technology in the Middle East, their only understanding is that the laser shoots directly onto the deck to the fixing position. Where this is true, Trimble has created different methods for you to set out your systems using the prism and pole procedure.
The enhancement of the direct reflex laser technology has been added and refined over the last few years. For the first few years of selling this device the laser was never even mentioned. As it did not suit the US workflow they have become accustomed to using the prism and pole only.
In my opinion the US has taken full advantage of the software products available to it and made sure there is true interoperability between office teams and their partners on site.
Coordination meetings take place months in advance to make sure all services can be installed correctly.
During my time there, the majority of the job sites used the ribbed decking and concrete pour format, so the setting out of their services actually takes place on the floor above before the concrete is poured.
Trimble technology takes that into account and gives the installers the exact X and Y coordinates of their hanger locations for the floor below. Once found they will use a concrete insert named a ‘Bagit’ and place an insert straight through the deck. Then simply the hanger rod is screwed in from the floor below. Yes this means no drilling. No setting out on a scissor lift. Haven’t even used the laser.
Using this procedure saves weeks of on-site installation time and can guarantee their services are set out within a certain set tolerance.
In the Middle East, contractors get on site a lot later. This may be due to the model not being signed off, the fabrication of their systems is not quite on schedule, or they prefer to wait for all walls to be in as it’s easier to manually measure. These are just some of the reasons I have heard in the market.
Most of my experiences on construction sites, viewing the installation methods in the Middle East, has been marking out on the deck above either on step ladders or a scissor lift.
So just because the installation process is different between the US and Middle does not mean the Trimble robot won’t work on site.
In fact my view is that the Trimble device is more suited to the Middle East market. As the direct reflex laser now has the ability to take site measurements into consideration, it can now move the point depending on the variance of the building and place the point on the exact location.
But if for some reason the laser is working on a deck or floor that carries reflectivity, then the prism is designed to give you that alternate method of setting out. Again this method is preferred in the US. Don’t forget this is a process change of how you install on site. These decisions on how to set out should be made weeks in advance.
One of my favourite quotes from my old customer was: ‘’My tape measure won’t tell me if I’m in the right spot, the total station will’’. You cannot argue with this comment.
I believe the biggest reason this technology has not grasped the Middle East market is due to personnel not being able to adapt to this type of a workflow. With the hesitance of a project manager and installers comes a lot more doubt with decision makers on whether this piece of equipment is right for them.
With BIM standards becoming more regulated it is vital that building services companies adapt to the specifications of setting out within a certain tolerance of the model.