UC Berkeley CoDesign Lab — Design for Sustainable Behavior in Generative AI Interactions
Published at ASME IDETC 2026 (IDETC2026-193320) — Second Author, with Nicole Goridkov, Diana Bolaños, and Prof. Kosa Goucher-Lambert
Reflective Resistance is a research through design project completed with the UC Berkeley CoDesign Lab under Prof. Kosa Goucher-Lambert, in collaboration with Nicole Goridkov (lead) and Diana Bolaños. The work was published at the 2026 ASME International Design Engineering Technical Conferences (IDETC), and explores how "design for sustainable behavior" (DfSB) strategies can be embedded into generative AI (GenAI) interactions to make their otherwise invisible environmental costs tangible.
We designed and built two artifacts that apply distinct DfSB strategies: a browser-based eco-feedback Chrome extension that visualizes real-time energy consumption during ChatGPT use, and a physical, eco-steering keyboard that dynamically modulates typing resistance in real time based on GenAI token usage. My primary contribution was leading the mechanical design and fabrication of the physical keyboard prototype, including the pneumatic bladder mechanism and the open-source heat-sealing fabrication method used to produce it.
The two artifacts were deployed together in a within-subjects user study (n=30), examining how physically-augmented versus purely digital feedback shapes GenAI usage patterns, cognitive workload, gaze attention, and reflective engagement with the environmental cost of AI.
Our approach drew on two DfSB intervention strategies. Eco-feedback informs users clearly about what they are doing through real-time data, while eco-steering goes a step further by structuring the interaction so unsustainable behavior becomes physically harder to perform, while preserving user agency.
We used Pierce's counterfunctional design schema to frame the keyboard's physical intervention: normally, a user can engage in high-frequency, low-deliberation prompting; our device ensures a user can not sustain that behavior without expending physical effort; as a result, the user is pushed to engage with GenAI more deliberately and reflectively.
We built a Chrome extension that overlays real-time energy metrics directly onto the ChatGPT interface. Once a prompt is submitted, the overlay updates with session time, a color-graded resistance status bar, and energy-use equivalencies (iPhone battery charges, Google searches, minutes of LED light, and estimated cost), alongside token counts per query and per session.
Tokens were estimated using the standard heuristic of one token per four characters, with a 60x multiplier applied to prompts that generated images, reflecting the substantially higher computational cost of image inference relative to text.
Exploded assembly (left) and the bladder's deflated vs. fully inflated states in the key-travel path (right, keycaps removed for demo)
The physical prototype is a mechanical tactile keyboard augmented with an
inflatable Thermoplastic Polyurethane (TPU) bladder positioned beneath the
key switches. As GenAI token usage accumulates, the bladder inflates to exert
variable opposing resistance against the user's keystrokes — to our knowledge,
the first mechanism to dynamically vary typing resistance mid-keystroke, rather
than relying on static keycap substitution.
Bladder inflation is driven by a motor-controlled air supply and Arduino
microcontroller, which receives live token usage data from the Chrome extension
and modulates air pressure via pulse-width-modulated (PWM) motor control.
I led the design and fabrication of the pneumatic bladder mechanism, developing an open-source method for using an FDM 3D printer as a precision heat sealer. Existing CNC-guided heat-sealing approaches for thin film lacked a fully open-source, geometry-agnostic pipeline, so I built a custom in-house G-code generation tool that accepts arbitrary bladder geometry in DXF format and outputs finalized G-code executable directly on a standard FDM printer.
Fabrication overview and 3D printer heat sealing.
Bladder fabrication. The bladder was fabricated from
double-layered 0.1mm TPU film, heat-sealed to conform to the negative
geometry of the keyboard's underside. Operated without filament, the
printer's heated nozzle served as a controlled thermal bonding tool guided
along predefined seam paths designed in CAD, exported to DXF, and processed
through the custom toolpath pipeline. This method produced far more repeatable,
consistent seam patterns than manual heat sealing, and the programmable workflow
allowed systematic variation of temperature, travel speed, and pressure depth.
Due to print-bed size constraints, the bladder was fabricated in three parts
and subsequently joined. The full method is documented and shared publicly for
future researchers working with soft pneumatic interfaces.
Assembly. The fabricated bladder was trimmed to accommodate
the keycaps and switches, then connected to an air supply via flexible silicone
tubing and 3D-printed valve splitters, sealed with rubber bands and secured
with 3D-printed retaining rings. The air supply, motor driver, and Arduino
microcontroller are housed in a 3D-printed enclosure, powered via a wall-connected
supply, with both the Arduino and keyboard interfacing to the host laptop over USB.
System feedback loop (left) and wiring of the Arduino, motor driver, and pneumatic air supply (right)
A three-stage pipeline translates GenAI token usage into physical keyboard resistance:
1. Token calculation — the extension's content script estimates token
count per prompt (1 token ≈ 4 characters), with multipliers applied for image generation,
accumulating into a running session total.
2. Resistance mapping — accumulated tokens are mapped linearly to a
0–100% resistance value (capped at 90 tokens), decaying 1.25% every 5 seconds during
idle periods to mimic a computational "cooldown."
3. Serial transmission — the resistance value is relayed through a
local Node.js/Express bridge server to the Arduino over USB, which maps it to PWM duty
cycle (60–100%) with a ramped step size for smooth motor acceleration and a 31kHz
switching frequency to minimize audible motor whine.
We ran an IRB-approved, within-subjects study with 30 participants to observe how each modality shapes AI use, perceived value of AI assistance, and moments of reflection. Participants completed a pre-survey, eye-tracking calibration, and a tutorial, then completed a ChatGPT-based image storyboarding task under two counterbalanced conditions: digital feedback only (browser extension), and physical feedback (browser extension + resistive keyboard). Participants thought aloud throughout, and completed post-task NASA TLX workload surveys, reflection questionnaires, and a closing interview.
Screen capture, audio, and gaze data (via the Beam Eye Tracker) were collected throughout, enabling both quantitative analysis of prompting behavior and a Locus-of-Attention Index (LAI) tracking how often participants' gaze fell on the feedback display versus the rest of the screen.
Distribution of prompt length, token count, and prompts per session across both conditions
Across 306 logged prompts, aggregate prompting metrics showed limited differences between conditions. Prompt length and prompt count were not significantly different, though prompt tokens declined slightly but significantly in the physical condition. Notably, variance was consistently lower in the physical condition across all three metrics, suggesting the resistive keyboard nudged participants toward more consistent, deliberate prompting behavior, even where central tendencies didn't shift dramatically.
Gaze tracking revealed that attention in the purely digital condition remained stable throughout the task, directed consistently away from the browser extension. In the physical condition, attention was similarly stable through the first half of the task but declined significantly in the second half. This shift may reflect participants checking the energy tracker more as resistance increased and they began to feel its effects directly at the keyboard.
Post-task NASA TLX surveys showed the physical condition imposed significantly higher Mental Demand, Physical Demand, Effort, and Frustration than the digital condition, while Time Pressure and Performance were statistically indistinguishable between conditions. Despite this added burden, participants in the physical condition reported stronger agreement that the feedback prompted deliberate reflection and helped them maintain an overview of their GenAI use.
Thematic analysis of think-aloud and interview transcripts surfaced 79 initial codes, refined into recurring themes around how and why participants reflected on their GenAI use:
| Theme | Subtheme | Description |
|---|---|---|
| Prompting reflection | Haptic | Keyboard resistance physically interrupting or slowing the act of typing |
| Digital | The visual energy tracker drawing attention to consumption during prompting | |
| Audio | Motor noise creating an auditory signal of computational effort | |
| Mental | The cognitive load of overcoming the hindrance itself prompting pause | |
| Behavior change strategies | Tradeoffs | Weighing the cost of further prompts against another factor |
| Prompt modifications & intentionality | Changes to how prompt composition was approached | |
| Ownership | Guilt and anxiety | Emotional discomfort arising from seeing one's own specific consumption quantified |
| Consequences | Environmental and resource costs that once felt distant becoming personal | |
| Digital feedback & intangibility | Unobtrusive nature | The extension's peripheral placement limiting how much it registered during tasks |
| Intangible metrics | Difficulty making sense of the raw numbers without a meaningful frame of reference |
While aggregate prompting behavior changed only modestly across conditions, interviews revealed that many participants meaningfully shifted how they thought about their GenAI use through negotiating real tradeoffs between output quality and environmental cost, and describing new feelings of ownership over their consumption. Augmenting digital eco-feedback with physical, embodied friction surfaced distinct patterns of reflection not observed with digital feedback alone, suggesting the two modalities are complementary rather than interchangeable. At the same time, several participants noted that current AI interfaces offer little scaffolding to act on this new awareness, pointing to an open gap between environmental awareness and actionable tools in sustainable AI interface design.
This project was my first deep dive into soft pneumatic actuation and closed-loop physical/digital systems, and pushed my fabrication skills into new territory.