With recycled wood, old pallets, used timber and a handful of connectors, Buro Happold engineer Nikul Vadgama built three medieval weapons of warfare for us, which we brought to the Secret Garden Party and Wilderness this summer. In between lobbing balloons full of shaving cream at unsuspecting punters at Wilderness and making bondage fetishists cry at the Secret Garden Party, he learned that “engaging the public with science” can mean many things. 

“How do we, as engineers, showcase the discipline of engineering to the public?” A question asked by many institutions, answered in several forms. For us, a group of engineers at Buro Happold, the answer was simple: “Let’s build catapults and fire paint balloons at buildings.”

Now, every good engineer must have a sense of pragmatism, and firing objects at London buildings using well-known medieval weapons of warfare does not present our industry in the best light. So timber cut outs of the London skyline were made by Guerilla Science and the title of the event was carefully chosen as “Paint the Skyline”, directing connotation to redecoration rather than destruction.

Trebuchets were chosen as the type of catapult as they are easy to construct and provided a consistent firing range. Three catapults were made all using old pallets, used timber, wooden dowels and a few metal connections.

The idea was to make a “Lego” set of catapults simple enough for anyone to build with a bit of guidance from us. There was some freedom to alter the pivot arm and weights to explain some Newtonian laws of physics to the public.

The test runs were successful, and the catapults ready to be taken to the SGP. However being stored in an open site in Newham, where tarpaulin is a high commodity and often stolen, the weapons of “mass decoration” were soaked by the British weather.

Arriving at SGP my excitement for the festival and the event was high, even though the rain was relentless! Friday morning I quickly got to work on constructing the catapults for a test run with help from my colleagues Gideon Susman, Victor Juarez, Joe Allberry and Ben Hall. Unfortunately the rain had soaked through the timber and although the catapults could be put together there was no way they could be repeatedly assembled and dissembled.  So we changed the idea to more of an “introduction to engineering catapults”. Furthermore the paint balloons were replaced with water balloons to avoid any health and safety nightmares.

These taster sessions proved popular with the SGP crowd, who couldn’t believe that there was no catch to allowing them to fire the catapults. After some deliberation, the weights were replaced with a piece of string, which when pulled went into tension, whipping the arm round. This sped up the firing and gave a greater range to the catapults. As the crowd became more competitive about hitting the targets, their enthusiasm to learn more about the mechanics of the system and how to improve their action grew.

Not everyone loved the catapults. Our neighbours the S&Empathy tent resented their existence as they were worried the water balloons may hit their tent and ruin the mood. Although we were baffled by how water balloons could ruin the mood of a session entitled “Introduction to Spanking”, Guerilla Science stepped in as peace-keepers and the catapults were moved out of harm’s way.

After a successful weekend of throwing water balloons at the targets the trebuchets were taken to Wilderness festival and used in the Future Cinema’s Bugsy Malone movie extravaganza.

With help from Chris Grainger, another Happold engineer, the catapults fired foam-filled balloons into the giant splurge fight. The catapults were used to the point of utter destruction in the fight. It was an explosive end for the catapults.

Through SGP and Wilderness festival Guerilla Science brought me to an audience like no other, full of enthusiasm, intrigue and alcohol. Not something I am used to in the commercial world of engineering consultancy. At times communicating engineering to non-engineers can be a difficult task. But Guerilla Science is always able to present science and engineering in a creative medium making it easy to get excited about. Definitely an experience I won’t forget.