PEAL is a laser-triggered, computer-controlled, light-sequenced emulation of an English church bell tower – or “campanile”. It gives audiences something of the experience of being inside an actual bell tower through the physical presence of its eight virtual bell ropes, high-quality spatialised audio recordings, graphical visualisation and (multi-screen) video display.

In a 3x3m footprint it models the layout and operation of traditional bell ringing mechanisms by replacing the bell ropes with an optical sensing system where lasers are used to trigger the ringing process of the individual bells. When a beam is interrupted by a player’s hand, the installation reproduces the ringing of the appropriate bell through a multi-speaker sound system, as if its corresponding rope had been pulled.

Se a video about PEAL here - http://vimeo.com/10197258

PEAL comprises several components:
• a set of eight two-metre-tall aluminium and acrylic columns, each equipped with multi-colour LED clusters and a laser sensing system;
• a microprocessor-based control system which senses interaction (the laser beams being interrupted) and allows the columns’ display to be controlled: the LEDs clusters can have their colour set to any RGB value, and the lasers can be powered on or off remotely;
• a host computer responsible for running the main program for the installation and for generating multi-channel audio for a surround sound PA;
• additional computers triggered via OSC over a local network running a) a Processing based user-interface and visualisation for the interaction between the columns and b) themed (multi-screen) video.

PEAL was originally designed as an interactive sound installation for The Leeds City Museum ‘Arena’, UK as part of the Sound And Music Expo festival in 2009. Although it was constructed with a specific application in mind the hardware and software of PEAL are decoupled and generic. Different control programs can be written and loaded to respond to the laser sensors and drive the LEDs, and the microprocessor system can be extended to respond to additional sensor inputs. The application software is also extensible, and brand new sound and video material, sequencing algorithms ,visualisations and user-interfaces and audio processing routines can be attached to the columns. The columns themselves need not be arranged in the traditional bell tower layout - they can be configured in any arrangement and orientation.

For these reasons PEAL was integrated into a ‘Light Pavilion’ project for 2nd Year students at the Manchester School of Architecture (MSA), Metropolitan University of Manchester, UK. They were asked to design responsive installation artworks for specific performance events in the city. PEAL was presented as a “construction kit” for creating a physical light-based work, whilst constraining the students creatively with a specific hardware “palette.” We were genuinely surprised by how inventively they re-imagined PEAL in new surroundings and how resourcefully they repurposed it for different types of interactive experiences. It seemed that PEAL had definitely managed to “inspire the innovator in everyone.”

With this as inspiration for developing PEAL into an open hardware and software framework for The Tech Museum, we now propose to use the hard and soft components of PEAL to equip ‘The Tech’ with a configurable, flexible, updatable “soft” artwork which can be extended and modified on a whim, by any artists (local or visiting), students and the wider Tech Museum community who have an idea for an interactive light-based work realisable on the PEAL system. 

We’ll start the ball rolling by providing the software and media for two iterations of PEAL ourselves:
a. The original incarnation as a virtual English church bell tower – or “campanile”;
b. The realisation of one of the four shortlisted projects by 2nd Year MSA students - available for download as PDF from http://www.monomatic.net/thetechmuseum/ This will serve as a demonstration of how the PEAL open hardware and software framework could be accessed and utilised. The particular student project will be selected by a mechanism as yet to be decided but which could involve staff and students at the MSA, MMU as well as the team at The Tech Museum.

Having designed and built PEAL from scratch we have all the design schematics, electronic circuits, bill of materials and practical experience to support its fabrication by The Tech Museum with supporting contractors - which we’re confident can be realised within the construction budget.

Additionally, a programming guide will allow artist/technicians with a modest degree of programming experience to develop, test and deploy artistic ideas. The PEAL programming interface can be exposed at a variety of levels, starting with MaxMSP objects - a media toolkit common in university and digital arts environments - and messages for dealing with incoming laser events and driving the LED clusters, down to a Python library for autonomous scripted behavioural “plugins” - which communicates directly with the microprocessor’s open-source firmware, or even a library written in C to allow artists to extend or modify the controller’s firmware. The scripting layers would allow an artwork to connect to the wider world online - over the Web, for example - and multiple artworks could be hosted in parallel, perhaps taking control in turns according to a specified calendar.