13. Applications and implications¶
This week we are to propose a final project masterpiece that integrates the range of units covered, answering:
What will it do?¶
A set of 4 translucent cast plastic parallelepiped blocks will glow a variety of colors based on their relative position to each other using magnetic fields. Importantly it will still look great and be fun even when the battery dies or the electronics fail.
Who’s done what beforehand?¶
Sifteo Cubes are probably my primary inspiration. They were built in 2008/9 based on Media Lab research. These are/were much more advanced than what I hope to achieve.
Bloxels are another example of interactive colored blocks. Bloxels
Legatos: Legos for Sound. This project used physical blocks to allow for arranging sound compositions. Fab Academy Project: Legatos
Interactive Cardboard Blocks Fab Academy Project: Cardboard Blocks
What will you design?¶
I’ll design the parallelepiped shape, including the molds for casting the shapes.
I’ll design the sensor that detects magnetic fields and powers an LED light to turn colors based on field strength.
I’ll design the interaction rules that determine the colors based on relative positions of blocks to each other.
What materials and components will be used?¶
Casting & Mold Making Materials I think I’ll try 3D printing the molds instead of milling. I wasn’t that impresssed with the Shopbot’s level of detail or VCarve’s toolpathing. My lab is equipped with a good variety of high-end 3D printers, so I think I’ll try them out. It should free up some limitations of milling, espeically handy when trying to embed the sensors and magnets.
Soft rubber material: O0moo30. This worked pretty well for my first rubber mold from week 6. I recall what was important here was the timing of stirring…not pouring too slow.
Hard resin material: SmoothCast326. This worked well for adding color - like 1 drop for a very translucent yellow.
non-stick material: Ease Release 205. This seemed less messy than a spray.
Sensor Components RGB LEDs Hall Effect Sensor double sided copper board? Resistors Capacitors Rechargeable battery and charging port Magnets - what size/strength?
Where will the materials come from?¶
Mostly from the lab supply, including these sources SmoothOn DigiKey McMaster-Carr These are all listed in Neil’s spreadsheet too
How much will they cost?¶
Mold making supplies Ease Release: $15.66/pint. My lab has a container already, so I will not buy a new one. Boston supplier
The soft rubber cans will cost around $25 for the pair. 1 each is needed for each rubber mold. I will be making 2 different cast blocks. one will be for the sensor board and the other will be for the magnet. I need 4 pairs at $25/each = $100.
The hard resin cans cost around $25 each as well, however i will less, even though i will be casting 4 final hard blocks. I think I will need 2 sets…so that’s $50.
I will calculate the 3D printing costs based on material alone, not machine time. This is for the hard mold. I will not be cnc’ing it out of wax. likely to be around $30 in printer material.
total for mold making = ~$200, rounding up.
Resistors are around 1 cent each. Capacitors are in the range of 5 cents to 18 cents each. RGB LEDs are around 53 cents each (CLV1A-FKB-CK1VW1DE1BB7C3C3CT-ND LED RGB 4PLCC SMD 0.53) Hall effect sensors are around $1.39 each (620-1402-1-ND SENSOR LINEAR ANALOG SOT23W 1.39) Attiny45 ~ $1.23/each (ATTINY45V-10SU-ND IC AVR MCU 4K 10MHZ 8SOIC- 1.23) Magnet: 469-1002-ND MAGNET 1-2”DIA X 1 0.98 Headers: 609-5160-1-ND 4 Positions Header Connector 0.100” (2.54mm) Surface Mount 0.66 Power jack: CP-002AHPJCT-ND CONN-POWER JACK 2.1MM SMD 1.47
~$10 in electronic components for 1 board (this project calls for 2 boards) = $20 electronics
PROJECT TOTAL ESTIMATE/RANGE: $200-$250
What parts and systems will be made?¶
sensor system boards with magnets casting and molding parts - top/bottom: one for the sensor blocks and one for the magnetic blocks.
What processes will be used?¶
I’ll need to program the sensor board to detect the magnetic field and in turn control the power sent to the RGB LEDs. I’ll need to set-up safe/clean casting station - get the timing or the pours correct.
For the Molding making process, I’ll 3D print the hard plastic mold which will be used to create the soft rubber mold which I’ll use to pour the hard resin.
What tasks need to be completed?¶
Design, 3d printing, molding/casting, programming the board, soldering and milling the board, embedding the sensor into the mold.
What questions need to be answered?¶
What battery? What rules of interaction to program? What 3d printer to use
How will it be evaluated?¶
Are they beautiful objects? How nicely finished are the blocks? Are they nice to handle? Do people immediately pick them up and enjoy them? Do I enjoy them? Do the blocks change colors based on unique relative positions to each other? Is there a nice variety of colorations? Will I keep these in my house for a long time? How nice is the color dispersion between blocks? Is there nice color bleeding?
Your project should incorporate:
2D design: sketching
3D design: Rhino software for mold designs
additive fabrication processes: 3D printing for mold
subtractive fabrication processes: cnc milling for sensor board
electronics design and production: EAGLE software board design for sensor schematic and board
microcontroller interfacing and programming: Arduino
system integration and packaging: the blocks will encapsulate/package everthing!