Drone Inspection Services: Using UAV for Aerial and Other Industrial Inspection Jobs
What is Drone Inspection
Drone inspection is the process of aerial inspection of industrial assets using commercial drones. Traditional method for the inspection of large industrial structures is an expensive activity and involves risk to workers performing the task. Drones can perform these inspection tasks in a cost-effective and safe manner. Drones can take aerial videos and images from various angles of interest. These videos can be streamed live to the experts sitting in a control room to help them make instant decisions. To successfully achieve the desired results, we need to implement a proper drone deployment strategy. Every inspection job is unique and therefore requires a plan tailored to the task in hand.
Many industries have started embracing the drone technology for the inspection of large industrial assets. This includes Oil and Gas, Mining, Energy, Communication and Building industries. These industries are using drone inspection as a part of regular maintenance activities. Traditionally, the inspection of large and heavy industrial structures such as high-tension grid lines, tanks, silos, turbines, high buildings, walkways, and bridges was performed using a handful of workers with a lot of equipment such as scaffoldings, cables, and ropes, cranes, etc. The insurance costs for working at heights or in high-risk environments usually are very high, and these conventional methods are high-risk methods. The same can now be achieved by deploying drones. However, this new technology demands specific new skills, equipment, and software to get the job done correctly.
Applications and Objectives of Drone Inspection
There could be countless possible objectives for any drone inspection. But the primary purposes of all drone inspections are to get a close-up view of hard to reach areas using aerial imagery, improve safety and reduce risk associated with the inspection of an industrial asset and to get high-quality data. Some of the applications of drone inspection are listed below:
- Inspection of thousands of miles of power lines to check the integrity of connections to avoid an unexpected outage.
- Surveying of oil and gas pipelines, looking for any changes or areas where maintenance is required.
- UAV Inspection using infrared cameras to get the thermal images and look for heat losses in industrial installations.
- Taking imagery of high structure and looking for signs of deterioration from engineering and usability perspective.
- Drone aerial imagery of storage tanks and silos and looking for leakage and corrosion.
- Close-up views of hazardous cargo tanks and vessels, containerships (enclosed spaces) in the marine industry. Sending crew and inspectors to these areas is a high-risk activity.
- Airborne inspection for an insurance company to process a claim.
- High definition Imagery of High Radio /Cellular antennas and towers, Inspecting the connections or even monitoring the signal strength.
- UAV inspection for calculating the volume of the excavation for precise payment to the excavating company. This can be achieved by deploying a drone with a LiDAR sensor.
- Drones can do inspection and monitoring of high radiation areas of a nuclear power plant, such as boiler rooms.
- Sometimes UAV is used for a preliminary initial inspection before the full maintenance of the industrial asset.
- Using UAVs to look for cracks in bricks and concrete during a building inspection.
- An inspection can be performed for gathering information about the surroundings for planning purpose. One example would be the forestry planning.
- Some inspections are mandatory by law. These are regular inspections of the assets looking for most common faults depending on the type of the asset.
- Inspection of any severe accident occurred in a hard to reach areas. One example would be an aircraft crash.
- UAV Inspection after a disaster, hurricane or earthquake.
- Inspection of roofs for damages or heat loss.
- Drones are also used for underwater inspection for multiple reasons.
- Inspection of bridges using high definition cameras to assist inspectors by providing close-up views of hard to reach areas.
Selection of Drone for a Particular Aerial Inspection Task
While selecting a drone for your mission, there are few important things to consider. The first thing is the ability of the drone to fly long enough to accomplish the task. Sometimes, this is achieved using liquid fuel in the drone. For the hazardous environment, seal batteries would be a requirement. The ability to carry the desired payload is also critical. You would be surprised to note that how little some drones can actually carry as a payload. Sometimes, you might need a drone which can look around or an upward direction. Not every UAV has this ability.
Also, in some industrial structures, GPS may not work, and drone should be able to operate without GPS. Maneuverability is another critical consideration for a particular task. The choice of brushless motors for the quadcopter could be necessary where noise or risk of spark is unacceptable. The range of the drone is an important parameter to look for a particular application. If the application is whether critical, then there are additional considerations such as the behavior of batteries at low temperatures and altitude hold capability of drone in a windy situation. One example would be wind turbine inspection.
Drones suitable for Aerial Inspection Services
Following drones are best suitable for various inspection tasks:
1. DJI Matrice 600 Pro
This drone is equipped with Zenmuse cameras. It inherits features from Matrice 600 with improved flight performance. Inspectors can point out damages of small sizes using cameras of this drone. The gimbal is 360-degree rotating. It gives complete control on the camera such as shutter speed, ISO, F-stop, and frame rate. It operates on 6 intelligent batteries. With a full payload of 13.2 pounds, the drone can fly for 16 minutes and up to 35 minutes without payload. The weight of the drone with 6 batteries is 9.1 to 9.6kg, depending on the type of batteries.
There are two models for batteries. The operating temperatures are from -10 to 45 degrees C. It has A3 flight controller which has flight modes such as waypoints, follow me or point of interest. The drone can be upgraded to A3 pro with three GPS units and three IMUs. The drone has a transmission range of 5 km.
It is a mapping and aerial inspection done. It has a superb field of view. The drone has the ability to capture stabilized aerial imagery in front, below and also above the drone. It has GPS, live-streaming and autonomous flight modes which gives you an option to choose from based on the application. It has both visual and thermal cameras. The image resolution is 1mm. The design of this drone best suits for the inspection of buildings and large structures such as bridges. You can also use this drone for agricultural and archaeological mapping. The drone can work in environments without GNSS. (Global Navigation Satellite System) GPS is one of GNSS constellations!
This drone has been used successfully for many inspection tasks. It has a compact, lightweight carbon fiber design. You can use this drone in wide variety of situations. The drone can detect inconsistencies in the structure using its visual and thermal cameras. (Sony 30X zoom camera and FLIR Boson IR camera as part of a dual spectrum vision platform) The drone can show close-ups of hard to reach areas with 30X zoom capability of the built-in Sony camera. It has the ability to mask objects real-time for privacy reasons. It can detect alphanumeric text such as number plates etc.
This drone is for the inspection of confined spaces or any other indoor applications such as help and rescue. You can deploy this drone to any area which is too hazardous for human access or just impossible. It has good tolerance to a collision at speed up to 15km/hr. This drone can transmit visual and thermal imagery simultaneously. You can operate the drone beyond the line of sight which may impose some additional licensing requirements in some countries. The drone does not avoid obstacles, instead, it bounces off and rolls on them to find its way.
Arducopter is an easy to use drone which runs on the ArduPilot/Pixhawk autopilot. It has a point and click mission planner and also a full ground station option. It has altitude hold and returns to launch options. You can script the whole mission using waypoints from start to finish and drone can then perform the task autonomously.
Data Collection and Analysis
We can use drones in a most cost-effective way to collect data. However, the selection of the sensors and software for commercial drone missions is critical for the success. Visual and thermal cameras are the two primary sensors for inspection. However, the hazardous environment may demand the use of extra sensors to detect the presence of any hazardous gases, etc. There are plenty of software available, and it takes time and efforts to understand the usefulness and limitations of any software.
For serious inspection work, you will also need a ground station with high-precision GPS survey equipment for the accuracy of the data you collect. For correction of the gathered data, you might need to pay for any third-party software in addition to your standard workflow software. If you are gathering a point cloud data, you will need additional specialized software to process that data.
Companies Making Supporting Products for Drone Inspection
- Septentrio Makes high-end GNSS Receivers.
- Airobot Makes UAV Radar Systems for Close Range Flying.
- Xenics Makes Infrared cameras.
- FLIR makes thermal Imaging Cameras.
World Leaders in Drone Inspection
Drone Inspection in Australia
- Australian UAV
Challenges for Drone Inspection
1. Long flights and Range
Drone flight time is still the biggest hurdle for large drone inspection projects. While specialized drones are available in the market which have longer than 30 minutes flight time, yet these are very expensive. Also, in some tasks, you cannot afford the interruption to change the batteries. This makes drones useless for larger inspection tasks such as disaster management or bridge inspection. The range of radio link is also a limiting factor for some inspection jobs.
2. Real-time data processing
Gathering massive amount of laser or imagery data is possible with modern sensors, however, the real-time processing of this data is still a big challenge. This is due to the software and hardware limitations. It is sometimes necessary to make live comments or take measurements of distance and volume and share them with the people sitting in a control room. This is not possible without real-time processing capabilities of the software and hardware. In addition to that, some applications such as nuclear may require 3D models with a precision of 1 mm. For this, the amount of data required is enormous which is difficult to process in real-time.
3. Multidisciplinary Manpower
It seems like there is a critical shortage of multidisciplinary workforce in the drone software development industry. For instance, a software developer with a knowledge about aviation, agriculture or mechanical engineering would be more beneficial for a drone software development company. These types of skills are hard to find in an individual.
4. Efficient Workflow
One challenge for drone inspection companies is to create an efficient workflow. This involves activities such as how to collaborate with teams, how to manage deliverable, insurance and licensing matters, contract forms, how to handle diversity in areas of demand, etc. There is plenty of drone software is available, yet, analyzing that software requires a lot of time and resources.
Deployment of drones offer significant benefits. The engineering and technology companies should learn how to leverage this emerging drone technology to help diagnose their problems in an efficient and safe manner. You can achieve this only by using very skilled first-class drone pilots, robust drone software and high-quality, affordable drones. Probably, there is a need for mission-specific training programs for drone pilots and other staff involved in drone inspection.