SAM
SAM is a project we decided to offer as a
seminar at the school for those who wanted to learn about basic
microcontrollers and how to interface them to the real world. SAM is loosely
designed on the 1stBot Robot kit that is offered at: Don Roy's 1stBot Site.
SAM uses a similar design that was used for
the cheap1.html series only SAM has a homebrew stamp for brains. The
Homebrew Stamp is available from www.phanderson.com and he offers educational pricing.
Homebrew
Stamp (with IR Detector on board)
Close
up of CPU, Oscillator, and Memory Module Wiring (takes about an hour to wire
the first one if you are experienced). You can see a larger picture of this at bs1.jpg
Using this setup, we can build robots for
about $60.00 and have a few dollars left over for class consumables.
Next step? Show them how to make a PIC do
the same thing and get away for even less money!
Parts
List For SAM
Next to several of the prices is a number in
parenthesis. This is NOT the quantity you will get for the price, it is the
quantity you have to order to get that price.
1. Homebrew Stamp from Peter Anderson (www.phanderson.com) - Price
varies depending on whether you are an educator/quantity/etc $18.00
2. JE23 Solderless Breadboard from Jameco (www.jameco.com) PN 20722 $6.95 (10 or more)
3. Servo Motors from Acroname which probably
aren’t the best ones to use. I would recommend getting the 300 series servos
from Lynxmotion if you want a quality servo. The cost from Acroname (www.acroname.com) is $9.90
(10 or more). Servo Motors from (www.lynxmotion.com) are $13.33 (6). Tower Hobbies
had a great deal on Futaba servos (good quality) for 9.99 and gave a $15
discount because I ordered 16 of them.
4. Wirewrap snappable headers. I’m having a
hard time finding these. There is a reference to something that might work on
DigiKey (PN S1032-36-ND) for what seems the right price at about 1.70 apiece
($17 for a pack of 10 36 pin strip single row long tail) $17.09
(10)
5. Resistors (330, 1K, 4.7K, 10K) These are
three dollars for a pack of 200 from Peter Anderson (www.phanderson.com) $12.00
6. Heat shrink tubing (3M). 50 feet
FP316B-50-ND (blue to get different colors, just change the B in the part
number to the color you want but look it up to be sure before you order it) at
digikey (www.digikey.com) $14.44
7. Wire crimpers and 50 insertion pins from
Lynxmotion (www.lynxmotion.com) $23.00 or you can order them
individually from jameco (www.jameco.com): PN 99442 crimping tool for $7.95 and FCH1 connectors (PN 100765) for
$6.00 per hundred. ($40 for a thousand)
8. Capacitors 10 uFd radial (from
phanderson) in packs of 10 $1.00
9. Capacitors 47 uFd radial (from
phanderson) in packs of 10 $1.00
10. 7805T voltage regulators from jameco PN
51262 package of 10 $3.50
11. Wheels I think a better deal on wheels
can be found. Right now, they are $2.50 each from Acroname and you need 2 for
each ‘bot. $5.00
You can get them locally for 4.25 . (2
½"). I got the wooden ones for .50 each at a craft store.
12. Battery holders for AA cells from jameco
(www.jameco.com). These come with a nice plastic connector that you
can chop off and use for the Stamp end of a serial cable connector, and they
have double sided tape on them already. PN105857 $.69
(10)
13. IRPD the IR Proximity Detector from
lynxmotion. These are pretty good but they are a bit pricey. $30.00
I figured a way to make them for under $10
using parts from several sources. You can buy it all at Radio Shack and still
stay under $12.00. See my web page ( /robots/ir.html )
14. Miniature toggle switches (SPST). These
are relatively expensive (over $2.00) in Radio Shack, but more reasonable from
jameco. (PN76523)$.89 (10 )
15. #4 self tapping metal screws about $2.50
a box of 100 from WestLake $4.00
16. LEDs (with resistor embedded). I use
these and still include a resistor because I’m paranoid about burning up a
Stamp port. PN MR3350QT-ND (yellow), MR3050QT-ND (red), MR3450QT-ND (green)
these are .45 each or .42 for 10 or more $.42
(10)
You can also get them from phanderson for
4/1.00
17. 9 pin D-Subminiature female connector
(for the RS 232 interface) digikey (www.digikey.com) (PN 209F-ND) these are $1.29 in Radio Shack or $.58 (10)
You can also get them from Jameco for about
.35 each if you order 100 or more.
18. Wooden 1" balls for the tail drag
(and some ¼" dowel) a package of 12 from the nearest craft store. $
2.00
Additional stuff you might want (most are
available at Radio Shack)
Volt Ohm Meter, Soldering Iron (think about
getting a solder station Weller Workhorse costs over $100, but it is very good
DigiKey has them), solder, solder sucker, double sided tape (a must), hot glue
gun (really kewl), solder flux, square 3/16 plastistruct for making standoffs
and other things, small screws and hardware (I just pick it up at Radio Shack),
hemostats ($4.95 at the Shack), wire (22 awg) in both solid and stranded ($4.50
at the Shack for packs of three rolls), dikes or wirecutters; wooden dowels.
This puts the price of making one item at
about $60.00 give or take a couple of dollars.