Bob was a very prolific contributor to the Arduino Forum, where he was a moderator, making 47,600+ posts.
Bob also joined Arduino Stack Exchange in February 2018, where he answered a few hundred questions.
Bob was keen on electronics, producing boards for the Arduino and other devices. His site was http://www.crossroadsfencing.com/.
In collaboration with his wife Kathy he wrote a book Arduino for teens.
He was also interested in fencing (with swords, not making fences) and aviation. He obtained his private pilot's licence and purchased his own aircraft, eventually getting an instrument rating.
His contributions to both Arduino Forum and Arduino Stack Exchange were invariably to help people with their electronics problems and suggest solutions. He will be sorely missed.