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Unlike a visible camera, a SWIR camera with range-gated imaging is able to penetrate through obscurants such as fog to determine what is cloaked in the fog, and would be a huge help to off-highway operators. This image was taken in late afternoon before dusk about 150 ft from the ground. The building shown here is around 1.5 mi away from the camera. (Sensors Unlimited)

Military technologies aid the fight for improved off-highway efficiencies

There is a never-ending need for technologies that can improve the efficiency of off-highway equipment, while enhancing safety for both operator and the machine. The defense sector of the industry has an upper hand in the investment and invention of such technologies, some of which could, and probably should, find their way into equipment used for agriculture, construction, forestry, and mining. Radar is one such example of technology that was once used just in combat applications, and was very costly, but now being widely used in vehicles for various applications.

Once closely guarded, many of these technologies are now commercially available. However, as these technologies are made to order and not being mass produced, at present their cost is higher compared to other technologies being used in off-highway equipment. But once they are introduced in vehicles and have with higher volumes, the cost will go down.

SWIR and range-gated imaging

Short-wave infrared (SWIR) works in wavelengths from 0.9 to 1.7 µm, which is not visible to the human eye. Although not visible, light in this wavelength has the same behavior as visible light, so the images taken from a SWIR camera are very similar to those taken from cameras working in the visible wavelength range. However, they are black and white.

In the military, SWIR is used for surveillance, reconnaissance, and night imaging. This technology can find many applications in off-highway equipment.

Off-highway equipment often has to work or drive in low-light conditions. Work lights and drive lights provided on vehicles may not be sufficient during dark and moonless nights. Also, these lights often provide illumination only in close vicinity of vehicle.

There is also a possibility of these lights getting damaged due to various reasons like damage to an electronic control unit, fuse or filament burn out, or smashed bulbs due to flying stones or timber, further reducing the intensity of light available for performing the job or the driving vehicle.

In the absence of these lights, SWIR cameras can provide excellent visibility at night due to their night radiance capabilities.

Since water is opaque to SWIR, such cameras can also sense moisture content. Objects having moisture content appear dark in the image taken by a SWIR camera. The more moisture content, the darker the image. Agricultural vehicles such as harvesters can leverage this technology to determine moisture content in a harvested crop, and thus help estimate the reduction in weight that can happen when grains are completely dried out. This may help in estimating accurately the cost of the harvested crop in advance.

In case of adverse environmental conditions such as rain, fog, smoke, dust, etc., visibility can be reduced to a level where it is not possible to see beyond a few feet. And there would be no way for the operator to know if such conditions were restricted to a few meters or spread over a broader terrain. The operator may keep driving the vehicle in an attempt to cross a low-visibility patch, which may lead into even worse climatic conditions.

Long-range identification may be critical in such cases. Simple SWIR cameras cannot improve visibility in these types of environmental conditions, so adding a range-gated imaging (RGI) feature aids in imaging at long ranges, minimizing the effect of adverse environmental conditions.

Similar to radars, RGI uses pulsed laser for illumination of objects. Light reflected from these objects is sensed by a camera. Here the exposure time (or "gate") is very short. Delaying of the gate enables the camera to capture only the light reflected from an object. Using this technology, one can see over a much longer range in low visibility conditions.

RGI technology can also provide underwater visibility up to 50 to 100 m. Thus, it can be used effectively in excavators to monitor underwater excavation work.

At present, most off-highway vehicles do not have anything that can see through clouds of dust, smoke, and smog, and best practice in such cases is to halt the work until the operator deems work conditions are safe and suitable, which may not always be correct. Use of RGI to improve visibility in adverse conditions can help the operator to more accurately sniff out danger before it is too late.

SWIR imaging is gaining popularity and is found useful in many areas, but in spite of its high potential of finding useful applications in off-highway segment, it is still not being used widely since it is not economically viable. Even more so, RGI cameras are costly at present (around $8000-$15,000) but they offer almost three times better visibility than the naked eye. Due to their high cost, they may only for now be able to find their place in high-end off-highway vehicles, or on jobs where there is a zero tolerance for mistakes and/or adverse conditions may account to casualties.


LIDAR (laser illuminated detection and ranging) is like radar, except that it uses a light source instead of radio frequencies. LIDARs are being used for terrain mapping, range-finding applications, imaging, etc., applications.

3-D LIDAR can be used to scan surroundings and can provide high-resolution images of approaching objects. For example, forestry log loader machines have to swing the logs to load them on the trailers. While rotating the logs, the operator could inadvertently hit the cab and potentially cause damage to the vehicle and/or operator.

Continuously scanning 3-D LIDARs can provide indications of a log approaching the vehicle. When the distance between the edge of the wood log and the vehicle cab goes below a certain distance threshold, the system would sound an alarm alerting the operator about the situation. Fully automated versions of this system could either stop the rotation of the attachment or reduce speed if the log got too close to the vehicle.

Currently, swing operation is done manually. If LIDAR were implemented, automated swing operation could result in higher efficiencies, saving both time and fuel.

3-D LIDAR is also a good candidate for construction equipment. For example, in an application that may require measuring pit geometry, a laser beam would continuously scan the surface and measure the geometry of a pit being dug. The captured data would be displayed in the vehicle real time.

Based on measurements before starting work and after finishing work, the final geometry of the pit would be shown on the display. By assessing the geometry of the pit, volume of material moved could be calculated, which could then be used by the contractor to pay the operator of the machine accordingly.

To assess the amount of work done in case of material movement, LIDAR could also be used to measure the size of the mud pile before starting and after finishing the job by construction vehicles. Moving a mud pile or digging a pit could also be automated using a LIDAR sensor.

LIDAR sensors are at present very costly and are not being used widely. They can, however, be found on some of high-end excavators.

Network-centric warfare gets nice

Network centric warfare brings networking techniques into war machines, which will help gather and distribute all the required information to rapidly aid in decision making while working toward one common objective. It includes works in four steps: gathering, distributing, analyzing information in real time, followed by decision making. This in turn helps to improve efficiency and gain operational edge over enemy.

Network-centric systems can help carry out work in a more efficient manner. When more than one off-highway vehicle is working on the same task, or the job to be done is too big and time consuming and is distributed over a fairly large terrain, using network-centric operation mode an entire fleet of vehicles can be deployed to perform the task in parallel, thereby reducing time required to finish the job.

One application when a network-centric operation would be useful is in a canal-digging operation. A fleet of construction vehicles is often deployed to dig a canal. These vehicles would be in constant touch with each other, broadcasting their GPS-based location where the excavation work is going on, amount of job done, direction they are moving toward, their fuel level, etc. This would give a fair idea of how much work is done, how much more time it would take, and could also aid in decision making for new vehicles to join the fleet.

Using a network-centric mechanism, vehicles that have finished their jobs can quickly analyze the work remaining of each other vehicle, and assess what direction to move in oder to help other vehicles finish their job faster, and without collision.

Lastly, all the technologies and sensors used on a vehicle for different job profiles may not be needed on the vehicle all at the same time. In this case, modular pods can be brought into off-highway vehicles. Modular pods are used in fighter planes for carrying a variety of payloads or sensor suits. Based on the mission profile, the pilot selects the payloads required on the plane. These modular pods are plug-and-play pods, meant to provide easy fitment, interfacing, and removal of sensor suites on the machine. Depending on the off-highway job profile—i.e. underwater excavation, work in hilly terrains or tight places, open areas, forestry, construction work, etc.—an operator can select the sensor pods required on the vehicle that day.

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