You may have noticed that I have recently been laser cutting almost non stop for about a week, regardless of numerous death threats (metaphor) from year 11 (who have probably failed their deadlines for coursework, thanks to me hogging the laser cutter). The slight problem was that it wasn't just coursework I was holding back. This is the post-mortem of our robotics team (but we still are the national champions). If you have read previous posts you will know that I am the electronics guy in our pretentiously names school robotics team (RoboCup Junior Soccer). We are a very disorganised team (Laser cut about 2 weeks before, all broken, hot glue, all works not very well, programmed badly on coach there) apart from the electronics, wich of course (being done by me) is always done perfectly, on time, without issue (er...). But this is not helped by the fact that the actual design could not be laser cut even 3 days before, as I had taken up all the laser cutter cycles for the matrix (oops, major lack of communication there...). The construction was completed by about 1:45 on Friday (competition on saturday). All the electronic modules (solenoid cap circuit, RC low-pass filter, motor controllers .etc) were all finished about three days before that (and tested might I add), but they couldn't be soldered in until the actual construction was done. So from 5:30 (when lessons finished) until about 4:30 the following morning (when we left) and a bit when we got there, me and Gabe (official solder-monkey of the team) soldered it all in. But we still only got 70% done by 45 before the first match (admitedly excessive soldering after construction might have been a slight design flaw). So, our (would have been) decent robot was not finished. But we quickly build backup robots (out of NXT, cue vomit), and actually won with them. Methinks we should get one big PCB next time. (P.S. the worlds are in Mexico City. We can't afford to go, but if anyone here happens to have £10,000 in spare cash that they want to donate within about 2 days, it would be appreciated )
Finished the glueing and drilling (with help from midget), Leds came today. Placing them now. Going well.
Here's the Pics as promised
All the boards cut, ping-pong balls are here, time to start sticking them on and drilling them. This time I can lay them out on one board and then glue them onto another (like a sandwich) which saves a lot of time (down to about 45 mins a board, 30 if I push it). Done three already, but now I have conscripted Midge (our captain for RoboCup) to help drill and glue, and have left him doing it, whilst my lazy self goes off home (he has to stay to 8:15 tonight, I go at 7:00). The dreaded task of soldering them is getting ever closer... On the plus side I have settled on how to attach them, with 2 3/4 inch flatbars, screwed at one end, whilst bolted at the other (disassembly for storage). No Pics yet, but will post when all done.
Ok, just finished laser cutting the MDF boards. This time in luxury "semi-waterproof" baby sick coloured MDF (might have to paint this time round). This time I have engraved it. In total I averaged about 3 boards a day (3 days). I have settled on a T stand, with possible addition of tank traps if it is to be used broken up as well. Next up is joining it, I'm going to just use bits of wood nailed/screwed to one board, then bolted (wing nut) to the next one along and above. I will post photos of the eight boards soon to this page.
Just finished the mainboard (not done connectors). It is basically a boarduino, with extra bits for purpose. Tis on vectorboard, and is yet more proof that I can't use it. I can solder literally anything perfectly in any obscure space, but for some reason, whenever stripboard comes out, I kill it.
PCBs have arrived, starting to solder them up. Waiting for the MDF to come so I can laser cut it. All designs finished.
The wheels are in motion
110 hours of soldering ahead of me, Happy Days...
Ok then, $4.30 Dev Board, could I resist ?
First I'll start with the price, which is (obviously stupidly cheap). But there is one problem. It's much more expensie here in the UK. I got mine from ProtoPic (albeit not the cheapest advailable, but average price). It cost me £7 (Plus shipping, which I am told is free in the US). This irritated me. But then I was thinking if it was in fact the cheapest board I could have picked up. After about 5mins of searching I had a result, much to my suprise, It wasn't. The PICAXE dev board, the XINO BASIC stole this title. But the two really cannot be compared. The XINO is the definition of bare bones. All you actually get in the kit is the PCB, 4 resistors, a 0.1uF ceramic, DIP target sockets, and headers (maybe a bit more, I haven't actually bought one) But you have to solder it yourself. And now for a list of what there isn't. FTDI (or similar USB programmer circuit), Power regulation, Crystal. In fact, you should really just think of it as a breakout board. Oh, and it dosen't come with the PICAXE chip. And you cannot compare the platforms, MSP430 is SOOO much more advanced than PICAXE (although SOOO much harder to use) (except for the massive PICAXEs, which are cool). But then we look at the Launchpad, comes with 2 different MCUs the MSP430G2231 and MSP430G2211. It is pre-soldered (save the headers), has a micro-crystal, USB, power regulation, and 2 IDEs !!!!! This is a really polished and complete package. But what if, like me, you just happen to be the worlds worst programmer. You may think that there is nothing but that PICAXE board above for you cheaper (or more easily remoed from the dev board) than the arduino. But here again you are mistaken. You can now, thanks to the wonderful world of open source, write for it just like (and in) arduino. There are libraries just for this. So there. In your face, XINO.
All in all, pretty cool.
BUT, there are slight problems. Firstly the IDEs only work on windows, with no wine compatibility. There are community compilers and debuggers (gcc msp, and an apple only one, of which I have no idea about). There is also a known problem of Windows showing the device as being assigned a COM port, but it not actually working (normally due to a conflict, but you can read more on google). Personally I couldn't be bothered resolving this, so I just used GCC on my ubuntu laptop. That worked, but all the tutorials (there isn't a lot of them) and documentation (even less) tend to have difficulties working with GCC. This is not good. But TI is not exactly known for being the most user friendly chip designers around. TI have clearly put a lot of work into this one though. All in all, good, so buy one, if you hate it, it's not like you had to sell your home.
NOTE TO TI (if you're reading, which you probably aren't)
Cost bellow about £15 doesn't matter, it's still very cheap. Spend the extra money making the software work, mainly the drivers and debuggers. Same applies to everyone with MOSFIT