Interaction Design History Spring 2026 | Week 5 | April 6, 2026
Contextual Computing & Systems
Agenda Overview
- Lecture: Contextual Computing & Invisible Interfaces (90 mins)
- Break (10 minutes)
- Activity: The Local Network sva-node (60 mins)
- Homework Overview
Lecture: Re-evaluating Weiser & System Integration
We've spent the last month building discrete inputs (cameras, ArUco markers) and outputs (receipt printers). Today, we look at the glue that binds them: the network and the context.
- Part 1: The Evolution of "Invisible" Computing
- Review: Weiser’s 1991 vision of computing disappearing into the background. Did it happen? (The smartphone vs. the smart environment).
- The "Invisible" Interface: When the system anticipates intent without explicit UI.
- The Pitfalls of Invisibility: What happens when the system is wrong, but you can't see the controls to fix it? (Discussing user agency and "Seamful Design").
- Part 2: Contextual Awareness
- How does a system know where it is and what is happening around it?
- Location & Proximity:
- State & Environment: Sensors beyond the camera (RFID, light, temperature, accelerometers).
- Part 3: How Physical Programs "Talk"
- How do devices communicate when they don't share a screen?
- The Network Topologies:
- Client-Server: Everyone talks to a central brain (like our WebSockets activity).
- Peer-to-Peer (P2P): Devices talk directly to each other (e.g., Apple's Mesh networking for "Find My").
- Protocols: The languages devices use to share state.
- MQTT: Lightweight messaging for IoT devices.
- WebSockets: Real-time, bi-directional communication (what we will use today).
10 Minute Break
Activity: sva-node
- In your terminal run
git clone https://github.com/cwervo/sva-node.git
- Follow the instructions in the README.md file to run the code, have someone next to you try connecting to your laptop's version of the code running
- Now we'll break up into small groups and try changing the code together
Homework