August 23, 2017 - Maintenance & Operations
A fast-growing number of countries have enacted regulations enabling companies to deploy inspection drones for their maintenance requirements, saving money and man hours, as well as avoiding more potentially hazardous work each year. As an aerospace and defense equity analyst at Goldman Sachs Research reported in 2016, “Drones are entering a new era. There’s the common thread of them increasing efficiency, increasing safety and doing so at lower costs.” The reported business sense is today manifested as increased effectiveness of drone inspections in institutional and commercial facilities management.
Drone inspection is not all about flying the drones. which is often less than 50 percent of the work. Drone inspection involves capturing, storing and analyzing large quantities of data — high-resolution photographs, infrared thermal images and videos — that are gathered during drone flight. The recording and processing of such data collected over time from the same site enables the most efficient “machine learning” to the benefit of the asset manager and operator.
Technology advances
Advances in drone technology are turning the cumbersome maintenance effort into a safer and more streamlined data-collection process for implementing maintenance management systems. This also adds value to overall management systems based on ISO 9001 (quality), ISO 14001 (environment), and OHSAS 18001 (occupational health and safety).
Regulations and safety factors require manned systems to fly at higher altitudes and farther from whatever they are looking at. Unlike maintenance requirements for manned aircraft, those for drones can be easily met because the equipment is generally commercial-off-the-shelf. Thus, drones offer a cheap and often advantageous alternative to manned flights because of their maneuverability in close spaces, smaller sensors and logistic. Drones can be ground shipped, but manned aircraft need to fly to the site. These features have made drones a safer, quicker and more accurate option for monitoring purposes like those for a construction or operational site. Operators can do post-storm assessments, view encroachment by trees and vegetation, and perhaps even secure safety cables for maintenance crew climbing a high-rise installation.
Portability of drones simplifies their shipment to places to facilitate the emergency operations plans of different facilities with the added advantage that inspector can avoid dangerous climbing while the quality of inspection is greatly enhanced. Once up there, some inspectors rely only on a cell phone camera to snap pictures of any problems. Drones are often able to allow technicians to complete traditional inspection tasks at a fraction of the time cost compared to traditional methods. Many companies feel constrained to limit the amount of on-site inspections performed due to the traditional cost of truck rolls, crane movements, personal protection equipment, safety standard operating procedures for climbing and so on. Drones have greatly reduced excess money spent on maintenance and repairs of large assets whether the company needs to deploy drone inspections outdoor or indoor.
Focus on benefits
The most vital deployment of a drone could be in a situation where maintenance personnel are preparing to respond to an emergency but do not usually know the problem or what equipment is needed until they arrive at the location. Using an unmanned aerial vehicle provides the opportunity for inspections to occur remotely so they can perform repairs more efficiently. In short, using drones for visual inspection provides benefits such as:
• inspection of areas that are difficult to access
• preventive maintenance planning and and optimized maintenance schedule
• access to areas that pose health, safety and environmental risks to humans
• quick on-site deployment of the inspection system
• authorized and qualified inspection personnel
• reduced downtime and costs.
Drones fitted with infrared cameras provide additional benefits. For example, identifying defective roofs containing moisture is a time-consuming and costly activity. Drones fitted with thermal imaging cameras can do a quick fly-over while taking infrared thermal images of the roofs. These thermal images can help inspectors easily detect failing panels, since defective roofs loaded with moisture emit more heat than those functioning properly. The ways in which drones can help eliminate costs on construction, monitoring and reconnaissance activities can vary from simple assessments to in-depth visuals, videos, thermal imagery, data processing, modeling and calculations. In each way, drones have proven useful to reduce excess waste across sites. Specifically, by performing site inspections, drones are able to considerably cut down on costs compared to previous methods, making their deployment a long-lasting and sustainable option.
Acquiring data
Using professional unmanned aerial vehicle (UAV) inspection services, maintenance and engineering managers can reduce the time inspection personnel need to spend on the building itself. Provided a mission’s flight route has been well-planned, a drone can collect imagery data that covers the entire building envelope in a fraction of the time it takes for inspection personnel to traverse it.
Typically, visual and thermal imagery are collected. After applying automated statistical processes to convert the imagery into a 3D point cloud, it is straightforward for skilled interpreters to identify locations and areas of deterioration on the building envelope. Since the data are being viewed in 3D, the roof and facades can be visually interpreted. As the data in the point cloud is geo-referenced with real-world geographic coordinates, a plan or a map can be provided to an inspection and maintenance team to identify areas of deterioration before anyone needs to climb any ladders or scaffolding, undertake rope-access procedures, or walk on a roof.
Long-wave vs. mid-wave
Typically, a roof-inspection company might use a mid-wave infrared (MWIR) handheld camera or a long-wave infrared (LWIR) unit to collect data using an airborne platform. The advantages and disadvantages to the agency undertaking the roof inspection and the customer need to be assessed in terms of the sensor’s technical characteristics and the implementation implications.
Handheld MWIR can increase sensitivity among reflective and cool roofs, and increased scaling values in output images can make results easier to interpret. However, the reduced dynamic range the cameras have could mean reduced sensitivity across all material types. On the other hand, using drone-mounted longwave IR provides a high dynamic range that leads to increased sensitivity across dark, cooled roof structures. But LWIR technology requires an increased expertise to interpret subtle differences in thermal capacitance among different roof materials, especially when highly reflective.
In terms of implementation, drone-mounted LWIR units do not require inspection personnel to walk on a roof. The entire building envelope, including hard-to-reach areas, can be imaged. Thermal ghosting or leakage is minimized by a high, straight-on view of a roof by a camera. A complete, geo-referenced report can be quickly provided to the client.
Drones equipped with a combination of sensors are revolutionizing building envelope inspections. At the moment, drones with thermal imaging, photo, and video cameras, as well as gas sniffers and other sensors, are performing a variety of inspection functions. The mobility and sensors allow the drones to analyze facilities for existing and potential defects safely, quickly, and efficiently.
Industrial Skyworks (ISW) is a commercial, unmanned aerial system (UAS) and data management solutions company with offices in Houston, Toronto and Trinidad. Founded in 2012 by pilots with backgrounds and expertise in aircraft safety systems, risk management and aeronautical sciences, ISW inspects buildings and oil and gas infrastructure using small UAS. They were the first company ever to receive Federal Aviation Administration (FAA) approval for night-time commercial drone operations and flew the first-ever FAA-sanctioned night flight in the United States in fall 2016. http://industrialskyworks.com/
