Building my first Beetleweight

[qbnut]

Hi all!

After following the live events for a while, I've decided to get my hands dirty and build a Beetleweight-class robot, with the idea of maybe competing in the future.

I've started with the drive system, bolted to a bit of hardboard. I'm building my own ESC rather than using an off-the-shelf one - if this fails though I'll be off to do some shopping at Botbitz

[qbnut]

So further progress made - it now has a chassis! The ESC is still being worked upon, the first design ran far too hot and I didn't lay it out in a way that heatsinks could be added easily.

IMG_20160501_213830.jpg

[Andy]

Looks nice, whats the chassis made out of?

[Craaig]

This is looking great for a first beetle build! I imagine you'll want to get your wedge properly scraping the ground at some point though, the wedge war is rife. Look forward to seeing your custom ESCs!

Also welcome to the community of Craig's in the UK scene! Fortunately unlike me you've chosen a sensible username so everyone won't think you're someone else whenever you post anywhere... (sobs uncontrollably)

[qbnut]

The chassis is made from uPVC. It's unlikely it would last long but it is quite light. The robot weighs in at 1.4Kg currently so has to shed some weight before anything like flipper mechanics are added.

It's very much in the prototyping stages to see what works at the moment!

[Andy]

Could probably add a thin steel plate to the end of the wedge to improve ground clearance and add some strength if needed

[mrsam]

This is looking like a great first build, nice and simple and an effective design if done right.

One thing i will say though your PVC chassis will not last very long against spinners, it's too brittle. If you're using any type of plastic i'd always suggest using HDPE sheet, it's easy to work with and will take spinner hits all day long.

[qbnut]

Agreed, I will take the advice and upgrade it to HDPE / Polycarb before taking it into battle! I like to work with real prototypes hence building this to work on. I can start to fiddle and tweak the other parts.

Plus it gives me the ability to learn how to drive it!

[qbnut]

More progress made today.

ESC prototype 2 is now built and working, and a flipper mechanism has been added. It uses a light torque servo that I had lying around to power it, I will be swapping it out for a higher torque one before it's finished. Even now it can lift its own weight if upside down, just about!

At 1511g, it's also slightly overweight. HDPE sheets are on order to rebuild the chassis, and when I do that, I'll make it shed some weight by a slight redesign including use of lighter wheels that should get it to come in under the limit.

[Eventorizon]

Looking good and maneuverable.

You need to re-balance the robot though as you won't be able to flip anyone with your flipper arm waving in the air like that.

[qbnut]

I think that was me intentionally opening the flipper! But yes I've learned a fair amount already, there are a few flaws that hopefully I can iron out with the rebuild

[qbnut]

Work has gone into a combat- ready chassis, made out of a mix of polycarbonate for the side panels and HDPE for the rest. Switched to Fingertech wheels and uprated the flipper servo. It's quite a bit overweight so there's still work to do to shed some weight by removing some of the plastic. But it's starting to look and feel a bit more like the finished job.

[Albear]

Nice!

[qbnut]

Much work done over the last month.

The self-built ESC has gone, replaced with 2x Botbitz 10A, primarily due to size - I currently don't have the means to produce something that small. Maybe one day if I build one for a larger weight category.

As a result, I've been able to lose a lot of weight by making the robot a tad smaller, and replacing the 6mm HDPE with 2mm in places, namely the base.

New flipper mechanism also fitted, using a 20KG servo and aluminium fittings.

[R9000]

Looks awesome, and definitely a lot more balanced than before!