wk16 | applications and Implications

Assignment :

• plan and document a final project

what will it do?

I'm making a animatronic (dragon's) tail that responds to touch. I'm would like that the mechanics move smoothy
and in a 'as controlled way' as possible. If time permits,
I will create various routine responses, based on the range of the sensors measurements.

who's done what beforehand?

Genaral speaking:
The concept of making a robot or animatronic is not new and has been done many times before.
Which makes it a bit disappointing that in terms of DIY projects, there is very limited documentation to find on the internet.

I ended up viewing a lot of DIY-ers on YouTube for a source of inspiration. (search term: animatronic tail)
There are a lot of end result movie's and photo's to find, but not the explanations of how and why about design/construction choices.

Me personally:

• since mold and cast week I've started researching how animatronics work and what would be a good approach to try it myself.
  My tutor has been helping out with counsel about this subject and encouraging various tests.


• the sensor board was my the week 10 assignment.
• the servo control board was my week 12 assignment.
• the servo board / sensor board network was my week 13 assignment.
• the mechanical design was my week 14 assignment.

what materials and components will be required? And how much will it cost?

general :
	3 plates of 4mm MDF (60 x 30 cm)	FabLab price: 500 ISK
	a plate of 3mm acrylic (60 x 40 cm)	FabLab price: 1500 ISK
	PLA	6 x 3Dprinted pieces in PLA: x 2 gram x 10 ISK
	a roll of fishing wire (pull strength of 10kg)
	24 little springs (12 mm long)	(packaged per two) 12 x 150 ISK
	2 tie wrap
	copper plate sticker	15 cm x 11 ISK (per cm)
electronics :
	copper plate (6" x 4")	200 ISK
	soldering tin
	band wire
	5V battery
	FTDI cable
	2 servo's	(+/- 10 dollar each)
touch sensor board:		(+/- 5 dollar)
	IC1 ATTINY45
	J1 (6 pin, FTDI)
	J2 (4 pin header)
	J3 (4 pin header)
	J4 ISP (6 pin header)
	R1 10k
	R2 1M
	R3 1M
	C1 1uF
servo control board:		(+/- 5 dollar)
	IC1 ATTINY44
	IC2 5V
	J1 ISP (6 pin header)
	J2 (4 pin header)
	J3 (6 pin header)
	J4 (6 pin, FTDI)
	R1 10k
	C1 .47uF
	C2 22uF
connectorboard with RST button:		(+/- 5 dollar)
	button
	IC2 5V
	LED
	J1 ISP (6 pin header)
	J2 ISP (6 pin header)
	J3 ISP (4 pin header)
	J4 ISP (4 pin header)
	R1 499
	C1 .47uF
	C2 22uF
Price total:		9240 ISK
		(60 euro) (80 dollar)

where will they come from?

Only the springs have been bought locally in a hardware store, http://www.fossberg.is/?prodid=772
rest of the materials come from the standard stock of FabLab Reykjavik.

what parts and systems will be made?

tail :

• a design for the acrylic (spacers) pieces
• they need to connect the ball joints
• springs need to be fitted in, near the ball joints
• the copper plate touch sensor stickers need a big enough flat surface
• a pressfit design is preferable
• the ball joints for the tail, 3D design for the Makerbot

servo's :

• there is a wheel design needed, so the servo's can pull wire's and create motion
• wheel needs some kind of pin holder to create tension on the wire

box :

• The box will that hold the servo's and tail in the right position
• angle of the wire's (between servo & tail) need to be softened (rounded corners) to prevent friction
• there needs to be a system to create more tension on the wire's when needed

what processes will be used?

• 3D printing with PLA
• laser cutting acrylic & MDF
• vinyl cutting copper sticker


• electronics: milling, soldering, programming board


• if time permits: molding & casting

what tasks need to be completed?

• debugging electronics
• testing and fine-tuning program

If time permits:

• create more lifelike subroutines, bases on the measurements of the sensors (like smacking back when pestered to much ...)
• make a second set of sensors
• fine-tuning the mechanical design, less as possible friction on wire's & better lightweight tail pieces
• make a mold&cast skin for the tail (to cover the sensors)

what questions need to be answered?

debugging: What's wrong with my coding? My code seems to get stuck in the get char loop...

what is the schedule?

22/23 may Lab will be closed because of a local event

26/27 may full workday's in the Lab

28 till 1 june I have no time for FabAcademy because of personal event

2/3 june full workday's in the Lab

4 june deadline project presentation

how will it be evaluated?

Animatronic should give a lifelike response when someone tries to touch it