Flyability’s collision-resistant Elios drone is the next step in safer remote inspections
In just a few short years, unmanned aerial vehicles (UAVs), or drones, have revolutionised inspection techniques. Having conquered outdoor and offshore infrastructure environments, they are now well-proven as a method of inspecting large internal structures such as silos, onshore storage tanks and vessel ballast tanks. Where next, then?
The answer, it would seem, lies in making them safer, more capable and easier to operate. The potential for drones to collide with the environments around them still represents a significant danger to infrastructure and to the equipment itself. In working to prevent this, the hope is that these vehicles may be deployed safely in ever-more hazardous environments, and will further reduce the need for human access.
One company leading the charge is Flyability. Founded in Lausanne, Switzerland in 2014, the drone designer and manufacturer is a spin-off of the country’s prestigious École Polytechnique Fédérale de Lausanne (EPFL). Headed up by engineers and co-founders Dr Adrien Briod and Patrick Thévoz, it has won numerous awards and accolades for its remarkable Elios UAV, billed as the world’s “first collision-tolerant drone.”
The innovation was partly inspired by the need for accurate inspection tools during the assessment of damage to the Fukushima nuclear power plant (NPP) in Japan, in 2011. Watching reports of the site on the news, Briod saw the difficulties faced by ground-based robots attempting to navigate debris, and by aerial vehicles operating in confined spaces outside of an operator’s line of sight, and dedicated his academic research to finding a way around it.
Housed in a flexible frame, the vehicle that resulted from this research is designed to enable inspection and exploration of the most inaccessible enclosed places, the company says, allowing drones to work in complex, cluttered or indoor spaces that were previously off-limits.
Bouncing off the walls Our attention should first turn to Elios’ defining feature: the unusual cage-like frame on the outside of the drone. Designed by Flyability, the patented spherical frame is made of carbon fibre “pentagons” covered with a soft coating. This helps to trim weight – the frame is around one-third of the total system weight – while the materials used allow it to sustain collisions at any point in the frame, at speeds of up to 5 m/s (18km/h), without affecting flight or performance; Elios simply bounces and rolls along its path.
Like many innovations, Briod took Inspiration from the animal kingdom – or more specifically from insects. Flyability marketing manager Marc Gandillon elaborated: “Insects are very efficient at sensing and avoiding obstacles, but also being tolerant to them – think of a fly hitting a glass window and recovering. Briod’s research looked to reproduce this behaviour in a drone.”
This has been achieved thanks to some clever engineering on the mounting. If a frame was fixed around the drone, any collision would roll the vehicle, push it upside down, and prompt a crash. Instead, the drone itself is decoupled along three axes, using a gimbal mechanism, allowing it to remain stable even in the event of a collision with a structure (or human). “Decoupling of the frame is the uniqueness of this drone,” Gandillion added. “When you have a collision this absorbs the force and a control algorithm that handles the stability of the drone will compensate for the shock, so the whole system will remain stable.”
Its overall diameter is just below 400 mm. This is another purposeful decision, as it renders the whole system slightly smaller than the smallest standard manhole – again enabling maximum possible access to potential inspection environments. Inside, modular components including the battery and SD data card are accessible by hand through the open frame.
To those familiar with drone inspection, Elios’ payload will look very much as standard, albeit with some high-end additions. Its primary equipment is an HD camera mounted on a rotatable head. This captures images above and below with a vertical field of view of 215° and a horizontal field of view of 130°. This offers a resolution of 1920 x 1080 at 30 frames per second, with adequate image quality even in low light. When brought into contact with a surface, the system can collect close-up images down to a resolution of 0.2 mm/px, with remotely adjustable exposure.
Simultaneously, the system also captures images from a separate thermal camera, in slightly reduced fields of 42° vertical and 56° horizontal. This system can aid leak and crack detection, as well as improving visibility for the operator in environments with very little light. For the rest of the time, the five arrays of LEDs should provide sufficient illumination to in front, above and below the robot. The battery offers enough power for around 10 minutes of flight and inspection on a single charge. This might not seem like a great deal, but given the planned nature of inspection missions, and the fact that Elios is designed for indoor use, rather than high-altitude flying, the swappable packs should provide more than enough flexibility for most applications.
Insight without line of sight Imaging feeds are logged to an on-board SD card, as well as being streamed directly to the pilot at a lower resolution, via a 2.4Ghz comms link. This bandwidth itself offers users a distinct advantage: as well as preserving a high quality of data transfer, this system does not require any special authorisation to operate. The strength of bidirectional signal between the Ground Station and the drone itself also allows for long-range travel, even when working beyond line of sight (BLOS). Based on DJI’s Lightbridge 2 broadcasting technology, Flyability says Elios is capable of maintaining a signal at 150m altitude, or 150m of tunnel with minor curves. In more enclosed environments, Elios should be able to work inside tanks, or throughout several floors of building, while the operator pilots it from outside. (It is also worth noting here that unlike flying drones outside, few governments have introduced legislation to regulate indoor drone flight, meaning Elios users should be able to carry out inspections without seeking additional permitting).
Using the Ground Station, the pilot has access to live telemetry data, including, among other things, battery, heading, altitude and flight time.
In May 2017, Flyability also introduced a range extender module, with a view to increasing the usable range of the vehicle in difficult environments, such as underground tunnels or a mine. The 20m extension line works as an accessory to the Ground Station, enabling an antenna to be placed in a more suitable location for the mission. For example, an operator can lower the unit from the surface into a 20m manhole, offering Elios better communication and longer range when inspecting the tunnel. This also allows the operator to remain at a safe distance from any potentially hazardous sites, without compromising the quality of data. The drone, meanwhile, will always fly within range of signal – limiting the possibility of recovery issues.
Applications InnovOil has already reported on the use of quadcopter drones in enclosed marine and oil and gas industry environments, but it is fair to say the added collision protection offered by the Elios system is a highly valuable proposition for asset owners and inspection service providers alike. Although Elios systems are sold directly to customers – Flyability has “no plans” to become an inspection services provider itself – Gandillon noted: “Inspection of storage tanks is the strongest use case we have in oil and gas.”
Typical tank inspections – whether onshore or offshore – require the unit to be drained, cleaned and ventilated before scaffolding is installed and/or rope access technicians can begin IMR work. Because drones are not inherently safe for use in ATEX zones, the first steps have to be performed anyway. However, an Elios system can then be dispatched to inspect the tank walls prior to scaffolding and technician work, allowing asset owners to plan a far more time and cost-efficient operation, and scaffolding only the areas which require maintenance. “Our value proposition is that you want to know where you have to do repairs before you start planning resources… If you know before you start scaffolding where you have to do repairs, it is much more cost-efficient,” Gandillon added. Elios drones have been used for many inspections including refineries, chemical and hydrocarbon storage tanks and marine ballast tanks. In one case, two 15m by 12m ballast tanks on CMA CGM’s Andromeda vessel were inspected during six 10-minute flights, a during job which lasted just two hours from deployment to completion. Moreover, the pilots operated the drone from above the tanks, without entering the structure at all – representing considerable safety and time improvements.
The company has its eyes on future capabilities too. According to Gandillon, ongoing R&D is focused on automation, ease of use, data quality and flight time. Automation will help when doing very systematic inspections. Improving operations in GPS-denied environments (where stabilising the system can be very difficult) is necessary to make the tool accessible to those who are not born as drone operators. Seeking for an always better data quality but also different type of data (i.e. 3D mapping) will help serving a larger range of customers. With the automation of flights, an extended battery life will start to be necessary. “All the research that has happened with outdoor technology, we definitely have the same indoors; it’s just that the constraints are different and the technology is maybe 5-10 years behind, for now,” he explained.
Nevertheless, the added safety benefits of a collision-tolerant vehicle such as Elios raise a number of intriguing possibilities across the industry. “Any environment where space is tight, indoors and difficult to access or highly regulated, then our drones start to be interesting and useful,” Gandillon remarked. With no shortage of such places in oil and gas, Flyability has plenty of interest to keep Elios rolling along its way.