Week 17: applications and implications

1. What will it do?

The Intermission Object is a handheld ritual device for finite, screenless breaks. The user picks it up and turns an outer dial to begin the intermission. Warm LED light slowly appears through the ribbed clear body. A geared DC motor drives an internal rotor with steel pins, magnetically coupled to the outer dial. If the user lets go, the dial moves with the mechanism. If they hold it still, the coupling slips and soft pulses are felt through the fingers. Light, haptics, and subtle sound respond to the state of interaction throughout.

The experience is finite, but its duration varies slightly each time. The user cannot know exactly how long it will last, and their interaction may influence the pace in ways that are not fully predictable. At the end, the motion stops, the light changes, and a haptic or sound cue signals closure.

2. Who's done what beforehand?

• Calm technology / ambient devices: Mark Weiser and John Seely Brown's foundational work on calm computing; ambient devices in general as precedents for conveying information through non-screen, peripheral means
• Fidget toys: Products like the Fidget Cube and spinner toys explore tactile engagement as a focus or anxiety tool, but without a finite experience or intentional ending
• Time tools for ADHD: Pomodoro timers and similar tools address time blindness but rely on numbers or screens
• Ritual and break design: Research into the psychology of micro-breaks and restorative experiences in workplace contexts

3. What sources will you use?

• Seeed Studio XIAO ESP32S3 documentation
• Adafruit learning system
• Arduino / ESP-IDF community documentation
• Braun design archive
• Firsthand experience with ADHD and time blindness as a primary reference for the project's motivation and design intent
• Research on restorative micro-breaks: Ariga and Lleras (2011), "Brief and rare mental 'breaks' keep you focused," Cognition
• Richard Klein, Cigarettes Are Sublime (1993), on the ritual, pleasure, and structure of smoking as a cultural and temporal act

4. What will you design?

• Jesmonite AC84 cast base: the bottom section of the object, forming the speaker chamber; cast in a mould milled from wax
• Clear resin middle section: cylindrical light-diffusing body with a ribbed texture to distort the warm LED glow; printed in clear resin
• Clear resin top dial: the rotating outer interaction surface with embedded magnets; printed in clear resin
• PLA/PETG top section: the upper structural part of the object housing the dial mechanism and motor; FFF printed
• Inner rotor with steel pins: the motor-driven magnetic coupling component
• Internal structural and mounting components: battery mount and component holders; FFF printed
• Custom PCB: integrating the XIAO ESP32S3, MOSFETs for motor and LED control, hall effect sensor input, and connections for haptics and audio

5. What materials and components will be used?

Materials:

• Jesmonite AC84 (base casting)
• Clear resin (middle section and top dial, SLA printed)
• PLA or PETG (top section and internal structural parts, FFF printed)
• Phenolic paper PCB substrate
• Neodymium magnets (embedded in outer dial)
• Steel pins (inner rotor)
• Bicycle headset bearing

Components:

• Seeed XIAO ESP32S3 Sense
• 5000 mAh USB-C battery bank (de-cased)
• Hall effect sensor
• MOSFETs (motor speed control via PWM; LED dimming via PWM)
• N20-style geared DC motor, 15 RPM
• Flexible COB LED filaments (2220K, 3V, 100mA each, wired in parallel)
• LRA haptic actuator
• Gravity TM6605 haptic motor driver module (DFRobot)
• Adafruit MAX98357A I2S amplifier
• 3W 8Ω speaker

6. Where will they come from?

• Fab Lab Barcelona inventory (XIAO ESP32S3, hall effect sensor, MOSFETs, PCB materials)
• DFRobot (Gravity TM6605 haptic driver, LRA actuator)
• Adafruit (MAX98357A I2S amplifier)
• AliExpress (COB LED filaments)
• FormX, Barcelona (Jesmonite AC84)
• Amazon (bicycle headset bearing)
• Battery bank: retail (repurposed from consumer product)

7. How much will they cost?

Component	Cost
Seeed XIAO ESP32S3	€7
N20 geared DC motor (15 RPM)	€6
Hall effect sensor	€0
MOSFETs	€0
COB LED filaments (10pcs)	€5
LRA haptic actuator	€2
Gravity TM6605 haptic driver	€9
Adafruit MAX98357A	€16
3W 8Ω speaker	€4
5000 mAh battery bank	€15
Bicycle headset bearing	€7
Neodymium magnets	€14
Jesmonite AC84	€19
Clear resin (SLA)	TBD
PLA/PETG filament	TBD
PCB substrate and components	€0
Total	€104 + TBD

8. What parts and systems will be made?

Made:

• Jesmonite AC84 cast base (cast in a wax-milled mould)
• Clear resin middle section with ribbed texture (SLA printed)
• Clear resin top dial with embedded magnets (SLA printed)
• PLA/PETG top section housing dial mechanism and motor (FFF printed)
• Inner rotor with steel pins (FFF printed or machined)
• Battery mount and internal structural parts (FFF printed)
• Custom PCB (milled and soldered in-lab)
• Firmware (Arduino/ESP-IDF on XIAO ESP32S3)

Bought:

• N20-style geared DC motor (15 RPM)
• Bicycle headset bearing
• Battery bank
• Neodymium magnets
• LRA haptic actuator
• Gravity TM6605 haptic motor driver (DFRobot)
• MAX98357A I2S amplifier (Adafruit)
• 3W 8Ω speaker
• Hall effect sensor

9. What processes will be used?

• Moulding and casting: Jesmonite AC84 base, cast in a mould milled from wax
• SLA / resin 3D printing: clear ribbed middle section and top dial
• FFF 3D printing: PLA/PETG top section, inner rotor, and internal structural components
• PCB milling and soldering: custom electronics board on phenolic paper substrate, in-lab
• Embedded programming: firmware for motor speed control, LED dimming, haptics, audio, and hall effect sensor input on the XIAO ESP32S3
• 3D CAD (Fusion 360): all designed parts, including parametric enclosure and internal assembly

10. What questions need to be answered?

• How will the intermission duration be determined internally, and how will user interaction influence it in a subtle, non-predictable way?
• How sensitive does the hall effect sensor need to be to reliably detect the dial magnets through the resin, and what placement and threshold logic works best?
• What firmware state machine governs the experience, and how are the start, active, and ending states defined and transitioned?
• How will the power supply be kept clean and low-noise enough to drive the MAX98357A I2S amplifier without audible interference?

11. How will it be evaluated?

• Functional: Does the magnetic coupling create the intended tactile experience? Does the hall effect sensor reliably detect dial interaction? Do light, haptics, and sound respond correctly?
• Experience: Does holding the object feel intentional and calming? Does the ending state feel like genuine closure?
• Fabrication quality: Is the Jesmonite cast clean? Is the clear resin optically effective as a light diffuser? Are the internal components well-integrated and secure?
• Accessibility: Can the experience be meaningful without visual attention, through touch, haptics, and sound alone?
• Fab Academy criteria: Does it demonstrate 2D and 3D design, additive and subtractive fabrication, moulding and casting, custom electronics design and production, embedded programming, and system integration?