Influencia - My first robot

The idea

Everyone carries values, principles and ideas into a room. When people meet, some of that passes between them, mostly without anyone noticing. Influencia set out to make that exchange visible.

The robots come in three families of four: yellow triangles, a blue stripe, a red zig-zag. Each pattern stands for a different set of values. Put people in the arena and the robots go looking for warmth. Get too close to one and it veers away, often to follow someone else nearby. With several people in the space, robots drift from person to person and patterns form that nobody planned. Visitors started trying to steal each other's robots.

How one robot works

An ultrasonic sensor on top sweeps left and right, measuring the distance to whatever is ahead, so the robot turns before it collides. A thermopile array on the front reads temperature. At switch-on the robot takes 17 readings and averages them into a baseline for the room. Anything warmer than that, a person or an animal, becomes something to move towards. It knows something warm is there. It has no idea who.

An Arduino Mini reads the sensors, decides, and drives two geared motors through a motor driver, with each wheel controlled independently. There is no choreography. The behaviour people read as character comes from that loop and nothing else.

Built from what we could find

The shell is a plastic bowl from a grocery shop across the road from the university in Elephant and Castle. The chassis is cut from a sheet of aluminium from a South London scrapyard. Some wheels came off my own toys; the rest came from a toy bus we bought and took apart. The two 9 V batteries sit low on the chassis to drop the centre of gravity and keep the robot steady. Inside, all twelve are identical.

Eight weeks, start to finish

We started with a team and a direction: physical computing, and an installation people could walk into. An early idea tracked visitors with cameras and followed them with projected coloured light. Two things survived from it, something that follows you and colour standing for a person, and the idea moved off the wall and onto the floor.

The first prototype was a square box carrying the sensors. We tested it, changed it and tested again until the behaviour felt right, and only then committed to building twelve. With eight weeks for everything, most of the work ran in parallel: sourcing parts while the design was still moving, writing code while the mechanics were being rebuilt. The hard part was making the key calls on time, so each stage could start before the last one had fully settled.

My role

I brought the team together and led the project as project and product manager: the plan, the parallel workstreams, and the calls that moved us from one stage to the next.

I was also hands-on. I drew the blueprints that placed every component inside a bowl not much bigger than two hands, sourced the bowls and the aluminium, and worked alongside the team through prototyping, testing and construction. Coy Chen led interface design, Anna Jansson interaction design, Sunny Shao usability and user research, and David McLellan development.

What it taught me

It was my first time designing interaction where the material pushes back. How a robot behaved depended on the code, and just as much on weight, friction and where each part sat. It was also the first time I led a team through build, test, rebuild. I still work that way.

Where it went next

In September 2011, Influencia was exhibited at the Alpha-ville festival in London. That December it was shown in the Emerging Technologies programme at SIGGRAPH Asia 2011 in Hong Kong as "Influencia: Living Life with Sentient Machines". Four of us travelled to present it.

Link: ACM Digital Library, https://dl.acm.org/doi/proceedings/10.1145/2073370