Team Thrifty /Fifty Build Diary for Bitza

**PJ-27** · 17th September 2010, 14:28

This is our build diary for our first robot, named BItza, so called because its made of bIts-of-this-and-bits-of-that

The theme for the robot is to re-use as much stuff as possible and spend as little money as possible.

I'll try and keep this up to date but firstly here are some early chassis photos. CAD designs to come soon. (Made in ProDesktop for anyone that went to school in the last 10 years!)

The chassis is made up of various types of steel, bolted and stick welded together.
The wheels and drive train are from a lawmover.
The motors, gearboxes, batteries and chargers came from 2 Argos value cordless drills at Â£9.99 each.
The ESC are two 2nd hand Electronize 15amp.
As for weaponry we plan on adding a flywheel made from a err... flywheel at some point but for the mean time I think it will stay a rambot.

[attachment=2:1cy2xgrk]1.jpg[/attachment:1cy2xgrk]
[attachment=1:1cy2xgrk]2.jpg[/attachment:1cy2xgrk]
[attachment=0:1cy2xgrk]3.jpg[/attachment:1cy2xgrk]

**PJ-27** · 25th February 2011, 13:48

It has been a while since I have updated this but there have been quite a few changes in that time!

The plan for this build was to make a robot for under Â£100 (hence Fifty/Thrifty). And so far we are on budget! The plan has changed and we are now aiming to make a Rambot Featherweight, instead of a spinner.

Here is the budget so far!

Drill Motors Â£20 (Â£10 each)
ESC 30amp Â£35
Radio Gear Â£15
Chopping Boards Â£20

Total: Â£90

The frame is made from scrap steel that was lying around the workshop. The wheels and mounts are from an old Lawnmower and the batteries are from old RC car's we owned. 7.2 NiMh 3K mAh.

Unfortunately the batteries are completely different in makes, previous use and rate of discharge. They just have the same stats and yesterday one of them shorted out while in the robot for reasons I can't find. So a bit of a step back unfortunately.

For charges we are using the ones we happened to have with batteries, which are rather old and charge incredibly slowely....

None the less though the build is coming along quickly! We do need to have a weight in though. Any suggestions of how to do this accurately?

Here's a photo of the robot so far!

[attachment=0:2g80c7zu]Bitza with Armour.jpg[/attachment:2g80c7zu]

**harry hills** · 25th February 2011, 15:30

looks like my kind of robot

**PJ-27** · 8th March 2011, 10:07

Quick update;

We have added some bike tread to the wheels, since we had some issues with too little ground clearance and minimal traction.

The radio tray has been re-designed to sit deeper in the robot to help keep it safe. This will also allow us to have a much deeper angle on our front scoop.

The tails on the chopping boards have been removed (see above photo) since we found they can be prone to snapping, and wouldn't want our entire armour breaking off if we were to land on them.

The Rx for our 2.4Ghz system has stopped working on us, in the process of replacing it.

Making up some spare battery packs from the drill's NiCad packs, better than nothing!

Designs have been made to give the robot some ears to stop it resting on it's sides without wheels, and designs for the scoop have been made. Rather close to the weight limit, so hoping we can do whats left within it!

**PJ-27** · 13th March 2011, 15:43

Made some more progress with Bitza.

Today we added the scoop on the front. Unfortunately due to the impending weight limit we couldn't use as sturdy a metal we could have hoped for.

The scoop is supported by 4 thick steel guides which are bolted to the robot's main chassis, which will help take the main brunt of impacts.

Still waiting for the new Rx to arrive (since the old one broke) and seem to have a bug whereby the robot is moving very sluggishly despite the batteries still putting out a voltage above their rating.

[attachment=2:bvhztuqb]Bitza with scoop 5.jpg[/attachment:bvhztuqb]
[attachment=1:bvhztuqb]Bitza with scoop 4.jpg[/attachment:bvhztuqb]
[attachment=0:bvhztuqb]Bitza with scoop 3.jpg[/attachment:bvhztuqb]