I was notified late Wednesday that I have been awarded the October 2011 grant from the Chicago Awesome Foundation for completing the full prototype of the Scanning-Tunneling Microscope. Their posting is over here. For the record, yes, I officially love the Awesome Foundation.
At nearly the same time, Make magazine blog posted an old video of me playing with the version 0.1 electronics and then Element 14 posted as well (wow, I’ve come a very long way since then – I need to shoot some new video), bringing in a flood of new folks over the past 48 hours. Hello new folks!
For folks who are new, here’s how things stand:
- The version 0.1 electronics in the video posted on the Make blog was a poor implementation of a good analog design with a microcontroller slapped to the inputs. I’ve since learned that analog is weird compared to digital, and getting those two worlds to talk properly involves a lot more finesse and art than science and equations (equations do get you into the ballpark, however).
- I’m nearly done with a complete redesign of the digital and analog electronics (now at version 0.3). The new electronics incorporates nearly complete digital control of the STM (I’m working on ways to further increase the control the microchip has over the STM to include gain control of the many op-amps). Thanks to Idea Petri Dish for the assist on analog circuit design and troubleshooting.
- With new electronics comes new firmware and software of course, which is in-process.
- I’ve done a very rough draft of the vibration dampening table design. I’ll be using a classic floating gravestone style table – a heavy slab of material suspended by rubber bands, surrounded by a support structure. It’s not fancy, but it works.
- I’m working with Bart Dring, of MakerSlide fame to design the rough approach (basically a screw, direct-driven by a 400 step motor and a 1/16th step driver, like the pololus popular with the RepRap folks).
- I quit my job to pursue my dream of working in the device design industry, so if you’re feeling particularly generous, please purchase a periodic table – 100% of the proceeds goes towards funding this project.
- If you want to find out when kits are available (soon, I hope), sign up here.
I just finished building the version 0.1.5 machine.
Here’s what I’ve been working on during the past month and a half:
- Fixed EAGLE routing flaws (thanks Dorkbot Chicago for a very timely EAGLE CAD class!)
- Fixed part specification flaws (it turns out that the digital pots I originally used can’t handle much more than 8V, I was giving them 18V – oops!)
- Built a completely new test machine from scratch, by hand (not as bad as I originally feared)
- Started an arduino shield based design (using adafruit’s excellent protoshield as a starting point)
- Started testing the MCP4912 DAC as a replacement for the dual 4911s, I’m currently using.
- Switched from arduino duemilanove to freeduino/boarduino for physical design improvements (I’d like to use the UNO, but I’m waiting/hoping for improvements in the USB functionality of that board before switching).
- Added a fast prototyping area for experiments.
- Stopped using magnets as fasteners for the scanning head – those were awful.
- Built a completely new physical support with improved tripd geometry and stability.
- Redesign the X/Y signal pathway to use the full +/- 9V range and be flexible enough to handle +/- 18V via switch and/or gain adjust (I’m only using +/- 5V now, and it’s not flexible at all).
- Redesign the transimpedance amp pathway to improve signal/noise ratio and gain.
- Investigate alternative approach mechanism designs.
Reminder: I’ll be showing the ChemHackerSTM version 0.1.5 at the Armand Hammer Museum in LA on Saturday afternoon/evening as part of CRITTER Salon’s Enormous Microscopic Evening.
This project is not dead, it’s just pining for the fjords!
Actually, I’ve been up to my neck in:
- rebuilding the circuit from scratch
- debugging software
- debugging hardware
- redesigning circuitry
This is all stuff that is slow and relatively unglamorous.
I’ve been working frantically because I’ll be in LA next weekend showing the microscope at the Enormous Microscopic Evening at the Armand Hammer Museum in UCLA on November 6th at 4pm, and I’d really like to have version 0.2 ready for the exhibit.
I’ve learned a lot in the past month – notably that I had made a few poor design assumptions (now thankfully corrected).
Many thanks to everyone for being patient, everyone who has helped me with debugging and redesign, and to CRITTER salon for inviting me to the Enormous Microscopic Evening!
I’m happy to announce the formation of a new Open Science group here in Chicago, called ChiOpenSci. We’re open to enthusiasts, amateurs, researchers, hobbyists, anyone interested in solving scientific problems using (and making) open source and open culture tools and philosophy.
New website here.
Google group here.
First meeting will be on Sunday, September 12 at 4pm at Pumping Station: One in Chicago 3354 N. Elston Ave.
Feel free to bring your enthusiasm and ideas for problems that are best tackled via open software style approaches. Also, all realms of science that study natural phenomena are welcome: astronomy, physics, chemistry, biology, math, engineering, and many more I’m sure I haven’t mentioned.