The Workbench

The Workbench
Making my Dreams a Reality

Monday, April 27, 2009

So what's been happening on the bench?

Been a while, these holidays haven't lent themselves to getting anything done.

Now the holidays are over, I have started doing stuff again, getting back into the swing of things.

So what have I done on everything...? Let me see, I have started building a CNC machine, Wired up the Go Kart, Built a wireless pair, Found a F&P Smart Drive motor, Updated to Ubuntu 9.04 (AKA Jaunty Jackalope), Build a water rocket launcher.

All that in one set of holidays :-O.

Sitting on my bench right now I have this:

This is the entire go kart electrics system. I also have a multimeter hooked up to read the temperature (max to date is 55°C). I got the battery pictured and another one, (same type), for free off a wrecker in Tirau. What I need to do is de-sulfate it. This involves building a circuit designed to de-sulfate. I will get around to it... The driver along with the MOSFETs does exactly as it should, and I am very pleased. The main problem at the moment is, because the battery is so old and crappy, I can stop the motor shaft with my bare hand. If I can stop it, so can the weight of the go kart right? After de-sufating the battery, it will be able to hold much more charge.

I mentioned earlier about the CNC machine. My dad saw the IT department of #####, (place of work), was having a MAJOR clean out. I scored a computer power supply (which is now dead due to unknown causes), 2 dot matrix printers, 2 scanners, 2 USB keyboards, a UPS, (Uninterruptible Power Supply), and two gigaset network phones (Can be made into walkie talkies).

Back to the CNC machine, inside the printers and scanners there were stepper motors, these stepper motors can be "stepped" by a computer. Each step is a few degrees. I have ordered some H-Bridge chips from ST Micro to control each motor (3 in total). I also realized I will need a controller for each stepper. The program I will use to control the CNC machine is called Mach3. This program has two wires per motor on the parallel port - step and direction. I will need to create an interface so the four inputs for the H-Bridge can be controlled by the two output pins on the parallel port. I have already found the driver, just a matter of building it.

I have built a new PIC Programmer, (maybe a PIC can be used for the driver...), same as all previous attempts. It is a JDM style progrmmer built onto a Kiwi Patch board from Andrew.

I haven't tested this yet as I have to revert to windows. I know there are linux programmers out there, but I really like icprog. Maybe WINE can be used instead.

Whats happening with the smart drive motor?

I will tell you. It has been rewired for 12v operation, and is currently being "decogged". This means I file each pole, (46 in total), into a nice curved shape. This will improve performance in low wind. I also have to build a new set of blades to drive the thing, it's much "chunkier" than all predecessors. Wood seems to be the best bet, but that will take a long tie, and I don't think I have all the tools to build them. So... Maybe I will have to give the PVC blades a try. I can cannibalize them from the six blade windmill.

Another project, yes another one! I am getting back into water rockets. After being inspired by George Katz from Air Command in Aussie. I have built the "Gardena" launcher, only I used a cheap aluminium socket from The Warehouse. The nozzles on these rockets are 9mm, giving more "burn time" than my older rockets (nozzle size of about 19mm).

Deal Extreme sells cheap Chinese crap. I found a nice cheap servo motor than will do the job nicely. By job I mean deploy the parachute. I have build a launch computer built onto a PICAXE 08M capable of pulling the pin on the parachute door. Previously I used the NSA, (Nose Seperates at Apogee), and this just sucked... I only ever had one success.

It was the greatest success of all time! There was a holiday program running at the park at the end of my street. All the kids had seen a couple of my launches, (failed parachutes), and decided to come outsude and sit down to watch. It was going to be my last shot of the day. I charged it up, pulled the string, and hoped for the best. To my surprise, and the the kids awe, the parachute deployed. It was absoloutely awesome to have such a big audience cheering away at something you yourself were amazed at.

Anyway, back to the computer. This computer detects launch, waits a short time, and then pulls the pin. This should be MUCH more reliable than old NSA...

Pictured is Version 1.1 Beta. I am currently at 1.2 Beta. Please note, the rocket has not yet left the ground.

Here is 1.0 Alpha:

In the real version, I do use the nokia battery. I have three old nokia phones, with batteries! I have used one here, one is on my bench, and one still powers a phone. I have soldered a jack onto the computer so you can recharge.

Wow, that was a lot to type. Guess that's what happens when you are as busy as me, and are too lazy to blog about it!

Hope you enjoyed reading =)


No comments:

Post a Comment