Group Assignment: Pottery Wheel

🏺 This is Fab Academy BCN page for documenting pottery wheel machine. Assessment guide can be found here. :::

🎉 Goal

We aim to make a working pottery wheel. This includes:

1. Create a spinning platform that stays as level as possible
2. Powered by a motor connected to power supply and microcontroller to allow adjustable rotation speed / direction

🎬 Final Video

🙌 Team

1. Tony
2. Susanna
3. Niels
4. Mike

🔗 References / Links

Working Notes files:

• https://www.icloud.com/notes/0a7FSFw9ANq43Fb9-TA7KoPcQ
• https://www.icloud.com/notes/014c6buKFosZEoWLz7lNXZFVA
• https://www.icloud.com/notes/09bgSNlEn0OnbMcXICdGMIvdg
• https://viaucdk-my.sharepoint.com/:w:/g/personal/nisc_viauc_dk/Edsl98FIKCdPoBLLCKq9QSEBAyChXCV5PVhhwONmTVL5Xg?rtime=tO1GwipY3Eg

📖 Project Documentation

From assessment guide - group page must cover:

1. Show how your team planned, allocated tasks, and executed the project (Group page)
2. Described problems and how the team solved them (Group page)
3. Listed possible improvements for this project (Group page)
4. Included your design files (Group page)
5. You need to present your machine globally and/or include an aprox. 1 min video (1920x1080 HTML5 MP4) + slide (1920x1080 PNG) (Group page)

✨ Team Project Planning

Initial tasks outlined below. The group divided work based on availability within the lab. We did not specifically assign tasks, but divided the work based on availability and need. As some team members were traveling they focused more on design and documentation.

Table coded with help of ChatGPT.

Phase	Date	Task	Details	Status
Design	3 April	Preliminary Design Discussion	Discussion on design requirements and constraints	Completed
	3 April	Create Detailed Design Plans	Include a stable frame: A box with a top; Design bearings and mechanical parts	Completed
	3 April	Specification and Dimensioning	Detail specs for motor, shaft, bearings, flywheels, pulley, wheel, etc.	Completed
Initial Testing	3 April	Test Drill Holes for Shaft and Bearings	Ensure mechanism is centered to prevent wobbling	Completed
	4 April	Enclosure Fit Test	Test for snug fit of box joints fingers	Completed
	5 April	Motor Torque Requirement Testing	Test motor with more torque if necessary	Completed
Construction	4 April	Bridge Design and Fabrication	Width: 80mm, Length: 415mm, Height: 15mm; include pockets and holes for shaft	Completed
	5 April	Enclosure Cutting and Assembly	Start and complete the cutting, and assemble the box	Completed
	5 April	Mechanical Assembly	Assemble shaft, gear, mount to base and frame; install motor	Completed
Assembly & Integration	8 April	Assemble wheel & box	Integrate mechanism and enclosure / box	Completed
	9 April	Electronics Setup	Install and test speed control electronics	Completed
	9 April	Test 3D Printed Bearing	Test leveling of the wheel plate with a 3D printed bearing holder	Completed
	9 April	Final Testing and Adjustments	Comprehensive testing of electronics, and mechanical adjustments	Completed	Tony
	9 April	Final Review and Quality Check	Review the project for any final adjustments	Completed
Launch	10 April	Final Presentation	Present the final version of the pottery wheel for global class	Completed
	10 April	Documentation	Complete and push documentation on group site	Completed

🛠️ Design & Mechanism

Setup:

• Motor
• 2 Acrylic Gears, cut with laser cutter - smaller gear connected to motor, larger gear to rotating shaft (gear ratio 4.5:1)
• Belt (add specs)
• Bearings to stabilize shaft (2x - one below belt/gear and one above)
• Mount / enclosing

Design Process / Key decisions:

• Friction sufficient to secure gears to motor shaft
• To make gears thick enough for belt, cut 2 copies of each from 4mm acrylic sheet and attached together with screw
• Gear ratio was calculated using grasshopper, constrained by length of band - we chose 20 teeth / 70 teeth to allow tolerance for band length
• Conducted motor and gear test, switched for more powerful motor (initial motor was not powerful enoguh to move gears attached to band, even before wheel added)
• Larger motor succesfully moved band
• Started with long shaft, however this proved unstable so we added internal platform closer to pottery wheel to minimize shaft length and increase stability

Calculations & Design for Belt Length & Gear Size & Position

Design and Tolerance testing for Gears

Enclosing

🤖 Actuation & Automation

Setup:

1. Power supply (AC current from outlet)
2. AC/DC converter
3. H-Bridge that outputs to the motor - MY1016 - rated up to 24 volts, 2500 rpm
4. H-Bridge controlled by Arduino which reads potentiometer (knob) and sends this H-bridge as PWM output

Design Process / Key Decisions:

• Initially attached power supply (outlet) to potentiometer to motor
• However, potentiometer is not made for high power consumption and couldn’t output enough power to spin motor
• Tried attatching potentionmeter to mosfet, as mosfet CAN supply required power to motor, which worked! Until… it burned out, after about 1 minute.
• Therefore employed an H-bridge (only rated up to 12V) controlled by Arduino / potentiometer
• Successfully spins wheel and changes speed, however future iterations should supply up to max voltage (24V) of motor
• Mechanism to stabilize wheel introduced friction, requiring more torque (either thru increased voltage supply, changing gear ratio, or both)

Prototype of Motor, Belt, Gear and Axle

This one worked for about 2-3 seconds, then the belt flew off.

☝️ Possible Improvements

• [ ] Reduce friction from additional bearings
• [ ] Switch out H-bridge to be able to supply max voltage