- 1 Chris Stratton
- 1.1 Electronics Website
- 1.2 Current Interests
- 1.3 Skills to Contribute
- 1.4 Past Projects & Experience
- 1.5 Wishlist Items
- 1.6 Tools possibly available for loan or donation
- 1.7 Please watch the curb for...
Note - I've tossed a lot of generic things on this page temporarily which should probably go on public pages in the long run
As some of my projects are nearing the point where I may release them as kits, I've started working on a website.
Suggestions for a real name welcome...
Within the hackerspace
- Specific application project utilizing a small ARM chip and some generic support parts - ultimately comprising a cheaper and more powerful alternative to arduino+wave shield which could have more general applications if I get around to doing a PCB. But I need a better approximation to a surface mount workbench than I'm going to be able to set up in my apartment.
- I'd like to have access to or at least join in hacking on a 3D printer, CNC, and/or "generic cartesian machine" which might take a variety of toolheads/probes. I have a lot of professional skills in embedded systems & firmware, and amateur machine shop experience, but what I don't have is space or enough need to justify doing the whole project myself. I would be substantially more interested in a machine with a working envelope the size of an adult human foot, which is a little bigger than most desktop models.
- Shoe making - specifically custom ballroom dance shoes. The ability to 3D print and/or digitize lasts (ie, plastic feet) would be very interesting
- Things that fly - given the urban environment, more along the lines of micro/indoor than outdoor class UAVs. I have some experience with indoor R/C helis, but a small semi-autonomous quadracopter/hexacopter project could be fun.
- Looking for embedded linux/general embedded/Android opportunities
- Ballroom Dance competitor, costume maker, and sometimes teacher
Skills to Contribute
- Low level software/embedded systems troubleshooting expertise.
- Anything involving a scope probe in one hand while typing one handed with the other
(Have been known to hit run/stop button on scope with toe when neither hand is available)
- Design reviews - ie, pointing out why that architecture proposal is not going to have the needed performance or extensibility
- Machining, mechanical fabrication, light carpentry
Past Projects & Experience
- Staff engineer doing electronics & software support for the MIT 3D Printing Group at the lab for manufacturing - powder-based rapid prototyping using inkjet technology to deliver binder, as commercialized by Z corp and Extrudehone/ProMetal
- Firmware, Embedded linux, FPGA, and software defined radio work for a company in NJ
- Historic Brass Instruments - shaping brass sheet with hammers and fire into the form of trumpets and french horns
- CNC lathe & mill conversions, mostly temporary to produce specific workpieces. Custom software and EMC2 (real time linux)
(should this be on a shared page?)
Good Soldering Iron
Either a metcal or budget equivalent. The RF/induction? heated models are so much nicer than resistive - quick heating, and the effective wattage varies by the tip chosen. All but the tip of the tip stays cool, so they are very easy to change. For a shared space, there's the benefit of having some shared tips, but if someone needs to do really touchy work they can bring their own tip they take particular care of.
- I asked the sparkfun people at Maker Faire what the iron they were using for their soldering demos was. If my memory is correct, it's the ["http://www.amazon.com/Aoyue-2900-Lead-Soldering-Station/dp/B000ZPUKQ4"], which looks like a very budget (<$100) unit of the same idea as metcal (ie, only the tip itself heats). Some net research seems to indicate these are sometimes flaky but can be fixed by tightening up the internal connections in the handpiece. Also someone claims they use thru-hole components and at Atmel micro - hacking potential?
Surface Mount Microscope
Preferably binocular - video add on would be a plus for when people are working together, but not essential. Probably look on the surplus market. Hacks of using a small video camera could be considered as a temporary stopgap, but really this is a tool with little equivalent.
It would be good to have a few arduino and other (ARM?) microcontroller boards and an FPGA board or two people could play with while gaining familiarity.
- Scope - obviously, sometimes there is no alternative. Though I get a lot done with thoughtful use of status LEDs when I don't feel like breaking out the scope.
- "Bus Pirate" or similar FPGA/CPLD logic analyzer. These are cheap and pretty capable.
- JTAG cables/programmers
- Public PCs
- For access to space reservation/use log, general web browsing, etc
- For use in specific projects
- Small-partition Win XP box for pesky proprietary microcontroller tools, with a saved disk image that can be used to clean it up regularly
- LCD monitor - we should have one large one suitable for multi-person projects. It would also be good to have a few small ones that can be used on CNC control computers, or FPGA/microcontroller projects with video out. Some with TV/composite in could be good too.
- Laptop usability/preservation gear - a bench and fingers covered with solder flux are not necessarily healthy for your machine. Perhaps one of those stands and some cheap USB keyboards and mice, maybe on an already-powered hub? Just brainstorming
- We'll need a bunch of powerstrips even after we do formal wiring
Tools possibly available for loan or donation
Presently Available for Use
- microwave oven (donate)
- 4-5" craftsman bench vise (loan at least initially)
- Canon Pixma cheapy printer. Essentially unused. Needs black cartridge, has unopened color
- Xilinx Spartan 3 FPGA kit (needs one status LED replaced) (loan)
- Netduino embedded ARM board (loan)
- Fez Panda embedded ARM boards (2) - one needs a production solder error fixed under microscope (loan)
Materials possibly available for trade or small quantity donation to other members for specific projects
- polycaprolactone plastic (shape-lock/friendly plastic/etc softens in hot water)
- 3" wide white pine boards 49" long
- low-VOC water based contact cement (not entirely solvent free though)
- small tank-tread robot base (spy gear ATV 360 toy minus the video components)
Items stored in CT which might be fetchable in the future
- sherline lathe & mill (Only has one motor which needs switching between headstock, one of which has a non-removable three jaw chuck. Lathe bed has weak steppers plus parallel port control box. Have mixed feelings about making this available - requires careful use to avoid damage.
- CNC & Motion Control Parts
- Largish steppers (but high impedance, won't get fast rapids from these)
- A few GeckoDrive Stepper and Step-servo drives
- 90v PMDC motor somewhat servoable
- US Digital linear and rotary encoders (mylar based)
- Big linear power supplies for drive amps. Several voltage options, but I forget them
- Big torroid to make a servo power supply
- Tubing draw bench (yes, it's obscure)
Please watch the curb for...
- PC's with true hardware parallel ports - these are a great resource for stepper-type motion controls and I/O projects. USB I/O not only requires more complicated programming, it has a huge round-trip latency which prevents doing any kind of closed-loop control across a USB bus. When true parallel ports can no longer be found, it's necessary to move the real-time loop into a microcontroller or FPGA downstream of the USB and use the USB only to drip-feed high-level commands and asynchronously monitor status.
- Inkjet printers - most have either a linear encoder strip, or for the original deskjets, a fairly high CPR wheel encoder. It's not necessary to keep the entire printer
- Production laser printers or copiers - ie, larger motion control stuff
- Sewing machines