First, the bad news. The Linux board has taken a lot longer to realize than initially planned. We're still in a development phase of the board and until that happens it's difficult to integrate the computer with the electronics on the spectrometer. On the other side, the prototype of the spectrometer works just fine, I've been working on getting an idea of how accurate it is and how much loss there is due to mirrors and such. Overall, it looks quite promising. Also, I have apparently not uploaded any of my schematics, designs, or materials to the repo, so I am going to do that as soon as I have the chance. Now, onto some new cool and exciting news.
We're always cooking up plenty of different things to work on, and currently we are designing and producing a fairly affordable manual pick and place machine. We're using standard chromed linear rail, and aluminum plate for the base and armature, with CNC'd plastic brackets holding everything together. We don't have a great estimate on price, since most of the base materials were from scrap (we've only bought the rails and bearings, which along with some other pick and place equiment ran ~$240). The base plate and armature could reasonable be built with some reasonably dense wood material like MDF or the like. I'll post pictures tomorrow, it looks reall cool.
The other thing we've been working on is a complete rework of the electronics for servo drivers in a machine we have at Lib3. The original servo interface was for IBM PC's ISA (obsolete) so that was disappointing. However, we opened up its casing to find 3 AMC 10A8 servo ampilifiers, and after fiddling with them for a bit and reading the data sheet, decided they were more than salvagable. So, the next step is to write firmware for the Stellaris to control the motor controllers using some external op amp setup to get the proper signal. The servo amps take a reference, and then a + or - to determine speed and direction. A microcontroller can do stop and one direction, or both directions, but cannot do all forms of motion needed to drive the motors by themselves. I'll have more details when we finish designing the external circuitry, but basically we are going to turn the machine into a big USB peripheral that will be able to do some serious macaroni art (if you'd like). And now a couple pictures. This is the test circuit I'm using to debug the motors. There is an Arduino nano pictured, but not used, although that would be simpler than an ARM chip.
This is an Astrodyne DC-DC converter. They're really cool devices if you ever need to do anything that needs a differential supply.
This is a closeup of our servo amplifiers. They're a little pricey, and we're lucky to have them, but they are industry grade amplifiers. I think that having an available interface to them would be useful in cases like ours, where people get secondhand equipment where most of the parts are perfect, but there are logistical issues preventing them from being easily used (e.g. you can't you its control interface because it was obsolete in 1993). But once again, they seem pretty solid.
That's all the news I have for now. We're continuing to work hard to bring open electronics to the world, whether its through the spectrometer, motors, or even mechanical devices to aid in the construction of electronics. Have fun, feel free to ask us any questions, things you might like to see, or even just your favorite color.
