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Earth Imaging and Remote Sensing

Ground-Based LIDAR in Afghanistan

February 1, 2005 By: Paul Mrstik, P.E. , Simon Newby


Just two years ago, traveling the 1,062 kilometers from the Afghanistan capital of Kabul to the northwest city of Herat could take more than one week. Known as Highway 1, the surface and several bridges along the road had suffered severe deterioration after 20 years of neglect and lengthy civil wars.

Mounted on a pickup, SideSwipe (left) collects LIDAR data along the deteriorating Highway 1 (right) in Afghanistan.
Mounted on a pickup, SideSwipe (left) collects LIDAR data along the deteriorating Highway 1 (right) in Afghanistan.

In November 2002, USAID (U.S. Agency for International Development) began a project to rebuild Highway 1 as part of its effort to create a safe and stable society in Afghanistan. The first phase involved de-mining, surveying, and paving the section of the highway from Kabul to Kandahar. The survey work was completed using traditional ground-based techniques, but progress was slow due to the harsh environment and safety concerns.

As a result, when work began on reconstruction of the section from Kandahar to Herat (the second phase of the project), alternative survey methods were considered. In June 2003, Mosaic Mapping Systems, of Ottawa, Canada, learned about the requirements and felt their airborne LIDAR-based system would be a suitable solution. LIDAR, or light detection and ranging, measures the time-of-flight for a laser pulse to strike a point on the surface of the Earth and return. A GPS/inertial measurement unit (IMU) subsystem provides the time and location at which the pulse returns. These two pieces of information can be used to determine the absolute position of the terrain point. The data collected by the system is used to create three-dimensional digital elevation models.

Although the LIDAR solution seemed ideal, military experts suggested that an airborne approach could be dangerous given Afghan-istan's state of unrest. In addition, finding an aircraft proved to be next to impossible. As a result, Mosaic decided to carry on the work using a prototype ground-based LIDAR mounted on a pole off the back of a pickup. The mounting method had its challenges, however. It needed to be designed in advance of seeing the truck on which the system would be installed. In addition, the system was normally powered by a 28-volt source on an aircraft but would now be powered from the truck's 12-volt battery. The ability to align the system without leaving the road was required, and the laser had to be adjusted to work in the high-vibration environment presented by the worn roads. Once these challenges were addressed, Mosaic introduced their new system as SideSwipe and was awarded the subcontract to survey Phase II of the highway.



In February 2004, the Mosaic team, accompanied by a heavy security force, completed the survey of the 566 kilometers from Kandahar to Herat. Using the SideSwipe system, the Phase II survey was completed in 45 days. This compared favorably to the Phase I survey, which took approximately 200 days to complete using traditional land-based survey techniques. Just a few months earlier, in December 2003, the Kabul-to- Kandahar section of the highway was officially reopened, reducing travel time from two days to five hours. Currently, the data collected by Mosaic is being used to plan for reconstruction of the road between Kandahar and Herat, the opening of which is scheduled for summer 2005.

With 35 percent of Afghanistan's population within 50 kilometers of the highway, the reconstruction will provide better access to markets, healthcare, schools, and jobs. Businesses will also benefit from increased ease of trade, thus contributing to the recovery of the Afghan economy.

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