Among the many exciting displays at the Technical and Vocational Training (TVET) event in mid June, the launch of a drone swarm which shifted its formation into text and images drew the most attention. It was the first such spectacle in Cambodia held at the Koh Pich Convention and Exhibition Centre.

One hundred drones soared above the rapt audience, glittering in red, blue and green, and formed the letters TVET to rapturous applause, before landing.

Then they stunned the crowd by changing formation to spell NPIC, then 2022. Finally, they ended the display by forming up into the iconic national symbol of Cambodia, Angkor Wat.

The fifth TVET Day was held under the theme “TVET increases work productivity and competiveness.”

Minister of Labour and Vocational Training Ith Samheng said that the TVET event had helped increase Cambodia’s knowledge and skills and would lead to increased productivity and attract investment.

Srun Channareth, professor at the University of Electronics Engineering at the National Polytechnic Institute of Cambodia (NPIC), who spearheaded the drone project, spoke about the display.

“At this event, we used 100 drones which were divided in to four ‘flights’ of 25 drones. Each flight was divided into five rows and five columns. Each of the flights could be programmed to form its own pattern, or a letter or number,” he said.

He added that the swarm were flown on the initiative of the Ministry of Labour and Vocational Training, which requested that his team create the display.

“All 100 drones were controlled by a single person from a single computer. We connected all of the drones to one server then checked to ensure they were all logged into the same network. Once they were all connected, we were able to come up with the patterns that the crowd saw at the event,” Channareth said, adding that the ministry had provided the drones.

However, he acknowledged that the launch had encountered many difficulties because it was their first time using drones in formation.

“We were trying something like this for the first time. We had plenty of experience flying single drones, but it is very difficult for one person to pilot multiple craft,” he said.

He added that it was very difficult to guarantee communication between the main server, the controller, and the drones. When the link was severed, the drones did not perform as well as they should.

The drones they used were educational models, rather than ones designed to be used for advertising. With the short time available, his team had to experiment to see what the drones were capable of.

“Education sector drones are different from those which are designed for automated applications. As such, they are highly programmable. This is both an advantage and a disadvantage. Commercial drones are pre-programmed, so they are effectively plug and play,” he explained.

“This was difficult, because educational drones are basically a blank slate. They ‘don’t know anything’ and I had to create a program from scratch. We had to study the drones carefully to understand their capabilities. Once we knew what they could do, we installed the program. Each individual drone required its own code,” he added.

Channareth said that commercial craft used in applications such as agriculture had specific pre-installed functions. Users simply activated them.

He pointed out that if any of the drones had an error in their code, they could easily have crashed into one another. While practicing, his team had often had to retrieve a poorly programmed craft.

He added that the project involved teachers and students, with teachers coordinating the technical work, and students as active participants. Students from the second, third and fourth years worked together, and as they demonstrated their results, the teachers offered feedback to help them improve.

A local sports fan, Suy Sovandy wanted to see a great show when Cambodia hosts next year’s SEA Games and ASEAN Para Games.

“I want to see more than cultural displays at the opening and closing ceremonies. It would be amazing to see a drone display. We have seen the beautiful images created by drones abroad, so why don’t we have one here? I believe that we Khmer can do it,” he said.

Channareth said that the TVET display was limited by each flight forming a five by five metric. They could show just one character and needed to land before being launched to form another shape.

“For our next formation, we would like to use 100 drones or more to form each metric, and we want to have them change colours and characters while in flight,” he added.

He said that if the private sector was interested in developing the technology for advertising purposes, his team would be happy to take on a project – in exchange for additional funding for his institution.