## 3 Methodology
### Re-Sounding Material  
While the main thrust of this project involved autonomous, self-organizing systems, we were keen to incorporate some established HCI models within the site, particularly to engage the children that we were hosting through our workshops at the garden. Building on prior research examining embodied approaches to sound and technology education [32; 33; 34], these workshops involved developing listening practices and exploring the garden in order to discover potentially interesting sounds through field recording techniques using hand-held audio recorders ([[https://www.zoom-na.com/products/field-video-recording/field-recording/zoom-h1-handy-recorder](https://www.zoom-na.com/products/field-video-recording/field-recording/zoom-h1-handy-recorder)]([https://www.zoom-na.com/products/field-video-recording/field-recording/zoom-h1-handy-recorder](https://www.zoom-na.com/products/field-video-recording/field-recording/zoom-h1-handy-recorder))). We appropriated an existing art installation comprising five colorfully-painted bicycles mounted vertically on one of the walls of a structure in the garden (see Figure 3). Our work in the garden utilized several Bela [35]-embedded microcomputing systems. Bela is a low-latency audio and sensor platform developed by Augmented Instruments Laboratory at the Centre for Digital Music (C4 DM) at Queen Mary University of London. Its ability to run software built in Pure Data (Pd), a commonly used programming environment for sound synthesis and design, allowed for the rapid prototyping, development, and composition of sonic interactions to be done on-site and in the surrounding environment. Comprising low-power processors, these systems were powered using portable Universal Serial Bus (USB) battery packs. Given the the subtropical desert climate, we also experimented with solar power banks. These certainly would have been a sensible option had we run the installation over a longer period of time. Figure 3: Children from Free Arts recording sounds from the site using portable sound recorders. By attaching need sensors to the bicycle forks, and a magnet on one of the spokes of each bicycle wheel, the children were able to perform the sounds that they had recorded from the garden back into the site itself. For this section of the installation, a single Bela was used to run Pd. Within the software, the speed of the rotation of each of the wheels was calculated from the time intervals detected by the reed sensors. The speed of the freewheeling was mapped in a nonlinear manner to the speed of playback of the samples. The recorded audio samples were stored in lookup tables and played back using both the digital sample position and low-frequency sawtooth waveforms. In the first case, which was audible when the wheels were spun quickly--taken as when the sensor was triggered at a frequency >1 Hz--a timbral effect was produced. The latter case--spin rate <1 Hz--allowed the samples to loop rhythmically, and then eventually slow down, and cease to sound. The children explored ways to play and manipulate their samples through the physical interfaces of the bicycles, using gestures similar to _scratching_ records with the wheels, as well as using physical objects pushed against the spokes to give audible added resistance to the spin. We also worked with MakeyMakey [36]--a low-cost electronics invention kit--connected to various plants and vegetation in the garden. By building simple connections, the plants and humans became part of a circuit. The MakeyMakey was connected to a laptop running software which, again, triggered various samples recorded by the children when the human-plant circuit was closed (see Figure 4). Through an exploratory approach, the children often connected different areas of vegetation in the garden and played these new instruments collaboratively. In some cases, more than one person had to be involved in order to complete the circuit.