Cape Town fire aftermath: drones fly in to assess the damage
The Cape Town resident watched helplessly as the fire swooped on his home, turning everything in its path into ash and cinder.
The fire had raged all day, engulfing South Africa’s mother city in a thick cloud of smoke, and virulently resisting all attempts to extinguish it by fire fighters. They had come prepared, which helicopters providing support from the air, while fire trucks took on the fire from the ground.
But the sun was high in the sky on April 19 – more than 24 hours since it had started on the side of Devil’s Peak mountain, causing city and university authorities to call for evacuations in areas – when they finally put out the last embers.
All he could do was watch and, just like every digital citizen in the world today, take a few pictures for posterity.
Also a student at the University of Cape Town, whose library became one of the lasting symbols of the destruction caused by the two weeks ago, the resident forwarded the pictures to his lecturer at the university.
“He sent me pictures of the flames approaching his home,” said Dr Walter Uys, co-founder of the Tech4Good Lab whose premises at the School of Information Technology escaped the carnage. “During the conversation, we started talking about how drones could actually be used to help manage fires by identifying heat spots with thermal imaging.”
Suddenly, Dr Uys was struck by an idea – how about flying in the drones to assess the damage caused by the fire?
Because, as Dr Uys says, there would be a lot of parties interested in the data that drones would gather.
“Insurers need to do an assessment of the damage. Architects need to know what steps to follow in appropriately securing and repairing the affected sites and then, of course, the whole UCT community.”
So, he got in touch with his friends at drone services provider and training company, UAV Industries, with whom he has worked on a number of projects over the past years.
Dr Uys himself has experience with manned aircraft, and his interest in unmanned aviation technology is therefore unquestioned. It should come as no surprise that when the idea of the Tech4Good Lab was first mooted at UCT, it was he and Dr Sumarie Roodt who were the main proponents.
The lab is a technology research facility which aims to harness the power of emerging technologies such as drones, blockchain, artificial intelligence and 3D printing to help solve the world’s most pressing problems.
And with a fire having gutted part of the university’s priceless reading material along with the infrastructure that housed it, the lab saw an opportunity to put drone technology to good humanitarian use.
UAV Industries were of course on board with the idea, and as soon as the red tape was done, they flew in their drones to assess the damage.
“We got everyone together on campus and it was agreed that capturing drone footage would be the most feasible option, especially considering the height of the buildings and the steep slope,” said Uys.
In the years before drones became an option, assessors would have been setting up infrastructure like scaffolding and cranes, on which people would have to climb so they could check the damage at a height.
It sounds dangerous just thinking about it.
Not to mention the added accuracy that drones offer, through precise aerial photogrammetry and other benefits that would not have been possible without drone technology.
It is a real game changer for industries like insurance and mapping, according to Braam Botha, Chief Operating Officer at UAV Industries.
“Without drone technology to assist with the insurance claim process,” Botha said, “the full size and complexity of the loss would be much more difficult, timely and costly to measure.”
To assess the damage at UCT, Botha and his team used a wide range of drones and photography equipment, as well as data analytics software. This includes a 3D survey of the damaged structures using high definition and thermal photogrammetry; 3D mapping of the inside of damaged buildings using light detection and ranging (LiDAR) sensors; and a full site survey of the upper campus and parts of the middle and lower campuses to document damage to roofs and track how the fire spread.
With LiDAR technology, the drones we also be able to map interiors and exteriors to look for defects beneath the surface; like steel structures that may have expanded, causing cracks which would destabilise the structure.
“With the data captured by drones, we are able to create 3D models of the existing structures and convert them into computer-aided design (CAD) models to indicate which parts of the buildings can remain and what resources will be needed to rebuild or restructure – all to an extremely high level of accuracy,” Botha said.
These 3D models can then be converted into centimetre-accurate 3D architectural models to assist with building redesigns and repairs.
Uys said that an additional benefit of conducting the drone surveys was setting people’s minds at ease about the extent of the damage on campus, especially in the wake of alarmist messages doing the rounds on social media.
“It’s really sad that we’ve lost two buildings and had some damage to others, but the good thing is that most of UCT’s buildings are intact. YouTube videos and Facebook photos taken from ground level simply don’t give you an idea of the entire impact.”
Analysing the data would take about a week, after which the relevant stakeholders would put it to good use.
“Despite the ongoing challenges faced by the drone industry in South Africa, there is still so much potential for the technology to help businesses of all shapes and sizes increase their operational efficiency and excellence,” said Richard Von Seidel, UAV Industries chairperson and director.