Software Review: IMSI/Design’s TurboSite for iPad

November 21, 2012 | Comments

By Rakesh Rao

TurboSite from IMSI/Design is a tablet-based software app that is refreshingly new and innovative. It changes the way AEC projects are managed, making site visits and field verification easy. TurboSite offers more than just views and notes. The key element about this app is that it is not just software at work, but a unique solution that is made possible by merging several hardware and software technologies.

Now, I must admit that when I was first asked to review this new tablet-based software, I was a little skeptical. Based on my previous experience, I expected to see yet another app offering red-lining or sticky notes on electronic drawings. But when I saw TurboSite running in an introductory Web demo, I realized I was seeing a technology workflow that was mature.

The creators of TurboSite cleverly exploit the multiple sensors available in iPads. GPS positioning, accelerometer, gyroscope, 3G/GSM, and the two cameras are put to use. TurboSite intelligently merges these with IMSI/Design’s home-grown CAD technology to arrive at a well-integrated solution for AEC professionals.

Imagine going on a site inspection with your laptop, camera, compass, level, and other measuring tools – and then integrating all the inputs from them into one place to generate a meaningful report for the design team or management. TurboSite does all this with your iPad.

Operating Requirements

TurboSite requires you to store drawings on your iPad, and does not require you to access data from the cloud. This is a big plus in the construction business where internet connectivity and cloud-aware personnel is not a given at all times.

I reviewed the product using a 32GB iPad 3. IMSI/Design says TurboSite will run on all the iPad models released so far. However, the functionality is limited by what the hardware can offer. For example, the iPad 1 has just 256MB RAM, and so can open 4MB-6MB DWG files at most, whereas this year’s iPad 3 and 4 models can open DWG files up to 30MB size. An iPad 1 has no cameras, so you would not be able to take pictures and videos; other functions work without any problem.


Figure 1: Cloud conversion option.

Input Drawing Formats

Native input formats supported by TurboSite are DWG, DXF, DWF, PDF, and 3D PDF. These formats can be opened in TurboSite directly.

Other supported formats are DGN, 3DM, 3DS, CGM, EPS, IGS, SAT, SKP, STEP, and others, but these require cloud conversion. (See figure 1.)

 Figure 2: A 3D PDF file in TurboSite.

Figure 2: A 3D PDF file in TurboSite.


Once converted, however, the data is cached in the iPad and can be used again without the need for an Internet connection. Thus, this file conversion is something that can be done in the office.

Once your data is loaded and opened, TurboSite offers a number of one- and two-finger gestures for panning, zooming, and 3D rotation. Certain CAD-specific gestures work in context-sensitive situations. For example, a single finger swipe pans 2D drawings but performs orbit rotations in 3D drawings.

My Test Data

I decided to test TurboSite with my own DWG data (see figure 3, below), rather than using the demo files supplied by the software company. I wanted to relate to the data first-hand, and so I started off with the floor plan of my house.

 Figure 3: The building plan used to test the software.
Figure 3: The building plan used to test the software.

There are many flavors of the DWG format. There are those created by Autodesk applications and those created with Open Design Alliance’s Teigha libraries. To test these flavors, I used AutoCAD and BricsCAD to save my floor plan in several DWG formats, ranging from 2000 to 2010. When I loaded the files into TurboSite, all appeared exactly identical. No loss of data or accuracy.

Figure 4: Layer control shows color and visibility status.

Figure 4: Layer control shows color and visibility status.

The Interface and Tools

The first thing that impressed me about TurboSite is the use of the voice, touch, swipe, and gestures that are intrinsic to an iPad. While on the field, the last thing I would want to do is to navigate through dialogs and settings. Most TurboSite features are accessed via easy gestures, and there are very few dialog boxes to deal with.

The TurboSite drawing interface supports layers, named views, and paper-space layouts. (See figure 4.)

Visual styles allow me to view 3D drawings with hidden lines removed, in a variety of perspective views, and with several styles of shading. (See figure 5.)

Standard 2D tools for red-lining and mark-ups allowed me to add comments and text notes. They can be saved into mark-up DWG files. Notes I made in drawing can be viewed in 3D with a leader that points from the eye to the viewpoint. In other words, I never lost track of my notes or need to zoom in and search to locate them. This is very a useful at outdoor sites, where lighting and other operating conditions may not be the best; easy location of notes is important.

 Figure 5: Visual styles display the 3D model in different display models.
Figure 5: Visual styles display the 3D model in different display models.

Once I opened my drawing in TurboSite, the first thing I needed to do was to mark my current location, calibrate my stride distance, and orient myself correctly. In other words, I had to tell TurboSite where I was positioned in the drawing and how long a given distance in the drawing measured on the ground. This is perhaps the trickiest part, and one that can take some time to get used to before getting it right. The more accurate your distance calibration, the better you can dynamically plot your position as you move around.

It is here that multiple sensors from the iPad deliver positioning information to the software. TurboSite uses the SPS (sensory positioning system) as well as GPS to read location information. Each has its own merits and drawbacks, because poor reception and interference to sensors render position information inaccurate.

GPS works well outdoors using satellite signals to obtain about 10-20 feet accuracy; it does not well indoors, because the signal is usually blocked. SPS works indoors and outdoors with accuracy within a few feet, but there can be drift and false movement since it is using the iPad’s built-in sensors. So, there is trade off in using either one. I would use GPS for outdoor tracking, and SPS for indoors.

While reviewing TurboSite, iOS 6 was released. IMSI/Design CTO Doug Cochran told me they are watching hardware and software enhancements and expect TurboSite to make use of iOS 6’s new Wi-Fi triangulation database to achieve better drift-free indoor navigation in a future release of TurboSite.

The locations and orientations of GeoMarks are fine-tuned using GeoNudge, a feature that can be used with any positioning system — SPS, GPS, A-GPS, WiFi-GPS, and so on — to provide pinpoint accuracy in drawings. GeoNudge moves the located position to the exact spot I am standing.

For example, a GPS has an accuracy of 10 feet at best. Should it cause TurboSite to indicate that I am standing in the middle of the floor, but I know I’m actually standing on the sill of the front door, then I can make the correction: I just drag TurboSite’s position indicator to the sill of the front door in the drawing. After this, TurboSite uses the iPad’s other position sensors to track my movement inside the building accurately.

I now could walk around the building and capture the information I needed by placing GeoMarks, which are like points of interest on GPS devices used in cars. A GeoMark has a From-To view indicator to tell me where I am looking from and to. On each GeoMark, I can tag information, like text notes, pictures, videos, and/or audio recordings — all taken with the iPad. The date and time of each recording is noted. All of this data is tagged to the GeoMark, which appears as a red circle with an arrowhead on the drawing. If necessary, I could fine-tune the location and orientation of GeoMarks using GeoNudge.

As I walked around the design area, a red dot with a searchlight beam moved with me; the red dot was my position, while the beam pointed in the direction I was facing. I went around my house and captured notes and pictures of the entrance, the old clock in my living room, the kitchen view, the bathroom water heater and the side board near the dining area. (See figure 6.)

 Figure 6: View of the side-board.

Figure 6: View of the side-board.

All of this gets saved to a TAP (TurboApps) file. IMSI/Design designed the TAP format to be a highly-portable container that holds many kinds of file types and assembles so that they can be easily distributed, shared, and/or archived in a single file. Think of a ZIP file that bundles any kind of file, yet doesn’t need PkZip or 7-Zip to view; instead, others view TAP files with the free TurboSite Reader app.

While the process of documenting site visits is easy with TurboSite, I found it even easier for others to view what I had inspected and documented. TurboSite attempts to make the flow of information easier within organizations. Manpower costs are one of the highest in any business, and TurboSite eliminates the need to organize personnel for a briefing of project reports and visits. I found that browsing through the TAP file in TurboSite Reader is easy, and everyone can review site inspection reports with ease.

By collating information from the site and tagging it spatially with a time-based reference inside a .TAP file, TurboSite has made it a breeze to know the outcome of any site visit.

 Figure 7: Saving the inspection report in TAP or DWG files.

Figure 7: Saving the inspection report in TAP or DWG files.


A TAP file and a DWG mark-up file is what TurboSite generates. (See figure 7.) While the TAP file can only be viewed by TurboSite packages, the mark-up DWG file can be XREF’d into the original DWG. The mark-up DWG is useful for the design and drafting guys who need to tweak their DWG files, based on the observations made onsite.

Building on the TurboSite Platform

No software is complete without the ability to customize and extend. A TurboSite SDK (software development kit) is planned for the future. This will be an interesting development to watch, to see if it opens up new uses for the software and localized app extensions.
I come from a GIS background, and so one format that I missed in this software is the ESRI SHP file. This file is used widely in geographic information systems, and it attaches information through a database. It would be nice to see this implemented in a future version of TurboSite. I could see logistics and delivery guys wanting to use this software with the SHP data that is native to many of them.

IMSI/Design told me that an Android version of TurboSite is in development. With new tablets launching on the Windows 8 mobile platform, I would guess that TurboSite for Windows mobile should not be far behind.


TurboSite is easy to use and offers just the right number of required tools in a simple interface.

For now, IMSI/Design is targeting TurboSite at the AEC guys, but I think it can be used by just about anyone going out on a field inspection or some multi-destination trip: travelling salesmen, supervisors on factory production floors, doctors doing rounds in hospitals, courier delivery agents, emergency services personnel, disaster recovery workers, insurance adjusters — all of them could think of ways to use TurboSite in their work.

TurboSite is priced at $999, but is currently $499 for a “limited time” at Apple’s App store. The investment is well spent for companies wanting to streamline project management and documentation of field visits. While the price of the software seems high relative to iPad apps, it costs about a day or two of field personnel salaries, a very easy case for return on investment.

About the Author

Rakesh Rao

Rakesh Rao specializes in DWG CAD software development, including designing add-on products. His expertise includes AEC, survey, mapping and manufacturing.


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