Richard and judy's favourite engineer

He got the second of these jobs after he appeared on a breakfast spot on the Richard and Judy Show – "I've got a card in my office with a thank you from Richard and Judy," he gushes.

As the designer of some of the world's largest roller-coasters, Roberts' early morning appearance was in the role of technical expert: "They decided to run a programme on roller-coasters and wanted to interview somebody who knew how they worked," he says. "I shared the programme with Denise Van Outen."

Roberts' television appearances are not confined to breakfast chat shows. Last week he was interviewed for a programme for Channel 4 about transport systems of the future. He has also appeared in the prestigious role of a judge on Scrap Heap Challenge, where he appeared with presenter Robert Llewellyn, best known as Kryten from Red Dwarf. "I put in a sterling performance on Scrap Heap Challenge," he says modestly. "I was judge on a challenge programme to build two demolition machines called Demolition Derby, which were then tested by demolishing part of Norwich power station. I was also a judge for the grand final, where two teams had to design a car-flinger that had to throw two identical Minis," he adds.

Making a television programme is a time-consuming process. "You do a whole day of filming, of which two hours is in front of the camera, and out of that two hours you'll get one minute of television coverage," Roberts says. However, he adds that the time spent is worth it: "If it gives engineering some exposure, it's good news."

It is unclear whether it was Roberts' ability to withstand a rigorous technical cross-examination by Richard and Judy, or whether it was his unbiased judging on the Scrap Heap Challenge grand final, that has brought him to the attention of another television production company looking for a presenter for a science and engineering programme. Whatever the reason, it seems likely that the viewing public will be seeing more of this gentleman in the future. "In the past two months I've done two screen tests," he beams.