Putting my money where my mouth is.

I have just ordered four Hub-ee powered wheels and matching cables from Cool Components. Well, I urged everybody else to do it so I thought I would get in on it too. My thoughts revolve around two scenarios, I can build a four wheel drive vehicle or two two wheel drive ones with a ball caster for balance. So I ordered the ball castor pack as well. I am also currently evaluating some free software, Draughtsight, to see how easy it is to design panels for laser cutting on. I know it will do the job but it also needs to be fairly easy to get accurate drawings as well. We shall see.

Worth a look

Is the latest from Cool Components. Amongst several new items is one that really rings a bell for me. The Seeeduino Stalker II is a very clever shield for the Arduino that has space for a wireless board, many different types, and also has both a battery socket and a solar panel socket. More investigation is needed but I would hope that the solar would not only power a board but also charge the battery. As the board has a charge management chip, I more than suspect this. At a cost of £24.99 this is very good value for money and a useful addition to a lot of projects.

On a more personal and immediate note, I have now moved the printer and workstation around in readiness for the rest of the work on the bench.

A clear working area!

For the first time since it was set up, my electronic working area on the bench is clear and all the components have gone into the racked bins, phew! The amount of space I have made is enough to enable me to begin the re-adjustment of all the areas on the bench and finally put computers and network kit in the various places originally assigned for them. The printer will be moving to the centre of the bench and my workstation to the right of it. The bench Raspberry Pi between the workstation and the electronics area and a space on the other side of the printer for working on the other PCs as and when. The network kit will go at the far end and take up as little space as possible.

At that point, I will sort out the things under the bench and, hopefully, make room for some more boxes to go under it. Then comes the main area of floor in the whole attic............................

A slight digression..............

I've been threatening this for months, I have now mounted my trays on the alcove and have just been busy doing some labels for the top half. I finally have a place for everything, now all I need to do is put everything in it's place! I've had a busy weekend, on Saturday I finished the new mains board for my soldering irons and on Friday, I replaced the 2 mm screws with the correct 4 mm screws on the hubs They are now very solidly fixed.

Woo hoo, again, woo hoo!

The test bed wireless remote control set arrived yesterday and, after setting it all up on a breadboard, it worked as hoped for first time. It's a digital, four channel system with a PCB receiver and a key fob transmitter. I was able to light four LEDs by pressing their respective buttons on the transmitter, that was very cool. Next is to set up the Arduino and interface the driver shield and the receiver to it.

Solvent Sticks

Well, the hubs are now completed and fit the main body really well. It didn't take very long to assemble and stick them together and then I assembled the whole mechanical side of the Trundle 2 for the first time. I know I'm biased but it looks terrific and balances really well. Next job is to load the continuous rotation sketch onto a Duemilanove and try a simple run.

This is a completed hub. The reason for building them this way is to produce a modular system for test purposes (initially) and so be able to swap drive systems and bodies around.

One view of the completed Trundle assembly. The body is, as yet, just a tube with no additional holes or parts added. In time I may insert a shelf so that the battery can sit in the lower part and the electronics in the upper. Also, there may be holes cut for sensors or parts mounted on the outside of the tube. A new set of hubs might have a motor drive rather than a servo. By using different hubs and bodies, the system becomes a 'Mix and Match' concept.

Behold, the Trundle Mk2.

More beer, more beer!!

A cry from my past.

 As I said, I did check whether the drive would be affected if I cut down the depth of servo on the outside of the hub. It doesn't, so that's the way I have assembled them .As you will see in the first picture, it makes the servo almost a flush fit with the 5 mm thick disc. A certain amount of jiggling is required to make sure that the body of the servo is on the same level as the disc but it's well worth that extra effort.

This shows just how much of the servo is now on the inside of the hub as compared to the usual mounting method. The servo itself is very stable and doesn't move at all even under pressure but the wheel will always be very slightly wobbly as it will never be a perfect fit due to the the fact that its not designed to be. Since this Trundle is only intended to be a full size test bed for the software, this isn't a serious problem. The servos will provide enough motive force to move the robot but not very quickly. In a test situation, this is a better set up than running at full speed.

The white adaptor piece (from the servo kit of parts) was first stuck to the hub and then screwed through into it in order to be as secure as possible. The screws used are M2 x 2 mm and should really be longer. The holes were drilled with a pillar mounted drill press to make certain that the holes were vertical and the tiny drill bit didn't break.

The saga continues......................

Yesterday, the Li-Po battery arrived complete with charger. The charger is the expensive part as it will be able to charge many different types of battery pack in years to come. The battery is fairly powerful but very small and light. I await with baited breath the very small self tapping screws and the solvent to weld the plastic as that will enable me to finish the mechanical side of the build. Then it's over to the electronic stuff. I already have a very simple script to run the servos continuously and that will do perfectly for testing. Later, when the remote control parts arrive, I will interface the receiver directly to the Arduino and begin to set up the remote and autonomous systems in harmony.