Team BLEEP build diary

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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

1 weekend left, so I guess it must be time to scrap everything I've done for Fermented Melon, and start again. :oops:

The night before last, I removed the tabs, made L-shaped brackets to hold the shell together, squeezed in the wheels, fitted the motor mounts, and found somewhere for the weapon motor to sit. It looked proper ropey! It was so strangely proportioned that I felt like I'd designed the Austin Allegro of antweights. It was supposed to be a lot sleeker!

And so last night, I made a more basic shell:
Image

Much more like it!

I just need to work out how to attach the top to the bottom, and maybe cover up the back and sides a bit. oh, and add an axe and electronics, but how hard is that? :roll:
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

Well, AntFreeze didn't go to plan at all! Where to start with the problems?

I'll gloss over the excuses, and just say that neither bot was ready on Saturday morning. They both drove (as far as I knew), but they had no weapons. I had the bits - I just had to put them together. Cue arriving at 10:30 and frantically trying to put together an axe and an extra layer of armour on Fermented Melon, and making a wedge for Sprouting Potato. Thank goodness sign-ins were allowed until 12, coz I needed all that time. :oops:

So, where did it go wrong after that?

Sprouting Potato
After my 3D printer jammed and started printing really badly, I had to resort to Potato's old shell from BotFest. Upgrades were some cheap 20:1 motors and a wedge instead of screws. The wedge plates are steel wallpaper scraper blades, which are a great fit, but maybe a little heavy. Mounting it on polycarb didn't quite work, as the polycarb decided it wanted to be straight again, and I noticed when I got home that the wedge was 10mm off the ground. :roll:

Image

I'd given the bot a quick test on Thursday night, and it was fine apart from front/back being the wrong way around. Easily solved in the tx!

But on the day it just didn't respond. The RX was powered up and seemed to think it was bound to my TX, but the motors did nothing. I still haven't taken it apart to find out why (need to appease the wife, so no bot stuff for a bit).

edit: gah! it was a tiny bit of frayed wire shorting the RX outputs. oh well - at least it works now!
edit 2: I had another look this morning, and my wiring was truly abysmal! The perils of rushing soldering at 2am. Don't do it, kids! :P

Fermented Melon
The melonbot finally makes an appearance! :P

After doing the shell, I spent most of the time trying to get everything to fit inside it. I always worry about DasMikros losing pads, so I don't like resoldering them, hence there was much silliness with veroboard. I need to rethink it, tho - veroboard is not the answer! It barely fitted, but I think I can do it better if I reduce the wiring. There's surely no need for so much of the stuff!

Image

The bot was driving well enough on Thursday.. all the controls were mixed up, but I knew I could fix that in the TX. It still needed an axe, tho. I'd wanted to use a nail, with the thinking that it might concentrate the energy on a point, but I hadn't thought of a way of actually attaching a nail to an arm. Then, by chance, I noticed that my Stanley blades had holes in them. 2mm holes! That'll do nicely, fanx! :D

Image

It weighed summat like 114g with the axe bits, so I decided to add an extra layer of polycarb on the top. I already had it cut out, and it allowed an easy way of attaching the melon decoration, so it seemed like a good idea. I made the axe and attached the polycarb (my son did the pips of the watermelon), and it was ready!

Except it wasn't - the wheels no longer touched the ground! :o

Attaching the extra polycarb had flattened the top, which wasn't flat initially. That had made the bottom bow out instead, and the bot was now resting on bowed-out polycarb instead of wheels. :oops: So, I took off two of the screws and it was a bit better. The tyres touched the ground, but I don't think they were in full contact. I had no time left, so it'd have to do. oh, and removing the screws meant the extra polycarb layer was up in the air. omnomnom!

Image

I had a bit of time to try and fix Fermented Melon's controls, but not quite enough. Fortunately, I'd found that if I turned the controller on its side, everything was in the right direction. Except the axe.

First battle, versus.. um.. I'm sorry, but I've totally forgotten the name of the bot! :oops: It was a nice looking one, tho. Sleek-looking! I had no plan other than aim at him and get stabby with the axe! Naturally, he got under me and rammed me into the wall, and I fumbled the axe to try and lever myself out. Unfortunately, the axe doesn't go backwards thanks to some battery-protecting armour, and I also got my directions mixed up.

Then, someone started counting us out! I wasn't certain who was being counted out, as I'd been stuck longer than he'd been still (he might've been making sure I didn't escape), so I didn't stop trying to lever myself out. In the end, it seemed that my opponent had gotten stuck, or stopped working. Victory! :D

Now that I knew I had some time, I fiddled with the TX settings, and got everything moving the way they're supposed to. My next battle was against Vanguard, which is one of my favourite bots (such a cool design!), and I knew I was gonna lose. I don't think I even managed to put up much of a fight before I ended up in the pit. :roll:

My third battle was against.. er.. that long-named bot that looks like a D2. I don't think anyone was in doubt about who would win. To the pit with me! :P

And that was that! I managed to stay to the end, despite my son going into orbiting mode (apologies to anyone who he bumped into), so I actually got to see most of the fights. It was nice sort-of meeting everyone (I'm not great at socialising, so hardly spoke to anyone) The obvious favourite bot was Lasagne, just for it's ludicrousness. GeorgeR's gyrobot comes a close second - I hope someone makes that at a larger scale! :D

I hope my zip ties helped those who borrowed them achieve great victory. I'll be back with revised bots for the next AWS. 3 weeks to go, and my wife's put her foot down on bot tinkering time. It's not looking good! :roll:
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

Time for a progress report, I reckon!

After AntFreeze, I decided to re-wire everything, and started with the worst offender; Sprouting Potato.

I'd done its wiring the last spare night before AntFreeze, at about 3am, and it showed! Wires were shorted in at least 2 places, and it's a wonder I didn't blow something up when I plugged the battery in. The wires were also way too long, so I desoldered it all, and tried to get the RX as close to the ESC as I could. I didn't do too bad a job at that. I even remembered to leave contacts for adding LEDs! :D Totally forgot a power switch, tho. :roll:

Next stage was re-doing the wires to the motors, and this is where I lose a week or so. They were originally wired using 22 AWG single core, as I couldn't get any of the multicore wire to go through the motor connector holes, but it seemed like a dodgy way of doing things. I managed to remove all the single core, but I needed a thinner and floppier wire, and ordered some 24 AWG wire from hobbyking. And some 1S batteries. And some decent solder. Anyway, that all took about a week to arrive, so no robotting for a bit...

The wire went to the post office depot, which added even more time, but I got it on Sunday, and decided to rewire Fermented Melon instead. It's much better for a haircut, although two out of the three motors broke contacts when I glanced at their dodgy single core wiring. I used header shims to fix them, but I haven't tested them yet.

Both bots now have new shells. Sprouting Potato has a 2mm polycarb base, altho technically it's the roof, as I'm building it upside-down to make it sit as low as possible on its large wheels. Fermented melon now has 1.6mm polycarb for the top and bottom, joined using a hinge. I might add something thin and green around the sides, for melony goodness. :)

Weapon-wise, Fermented Melon's blade can now go fully backwards, thanks to using 1S batteries, and I've increased the reach a bit. I'm not sure how much it weighs (it was 30g underweight at AntFreeze), but I suspect the hinges will add an annoying amount. ah well - it needed ballast.

Sprouting Potato might have a wedge, or it might have spikes, or it might get a wedge with spikes.. I have no idea, yet!

So, all looking okay for AWS, so far! Maybe this time I'll remember to use the axe for more than just trying to self right. :P
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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Kyro
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Re: Team BLEEP build diary

Post by Kyro »

do you have enough power in the axe to use it as a flipper/lifter?

figure you could make a dual purpose weapon or even one you could switch out depending on your opponent...

failing that, i could try and make you an axe head to bring along to aws... any particular type of axe you would like?
i have some offcuts of 5mm o1 tool steel i could use... or a fair bit of 1mm spring steel i could harden...
id just need to know either the spacing for the holes or the length of your axe shaft so i could try make one in maybe 1 piece... if you wanted 1 piece then id like to know the hole spacing on your mount attached to the motor... i cant guarantee itll be successful, but il see what i can rustle up for you if you want
Team Rocket
Trappist 1(4wd grab 'n' lift)
Ton 618 (4wd expanding bot)
Io(4wd flipper)
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Re: Team BLEEP build diary

Post by voorsk »

It's only a 50:1, so probably not powerful enough to do any lifting, especially with a long arm taking away all the power. It's an interesting idea, tho..

Thanks for the offer of the axe head - sounds like you know what you're doing! I think I'll stick with the razor blade, tho. Partially coz the idea has grown on me (it won't go through much, but it does dig in), but mostly because I'd feel bad about someone else spending time on behalf of one of my dodgy creations. :roll:
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

BLEEP-ing immune system! I was really looking forward to AWS, even tho my bots were possibly even worse than at Antfreeze, but a cough turned into a chest infection, and I had to spend the day coughing at home instead. :(

Sprouting Potato wasn't even close to finished. The pad fell off the original RX, and then I tried re-using the RX from the defunct NanoTwo. It didn't work, which gives me hope that the ESC part of it might still work.

Fermented Melon was nearly done, but I hadn't worked out how to do the side armour. Still haven't, really. It's a wee bit open at the mo.. :P

Image

Next event is BotFest in a month. I'm sure I can work something out before then. :roll:
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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Kyro
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Re: Team BLEEP build diary

Post by Kyro »

i would have cut either the top or bottom polycarb with tabs that would be bent up (or down) that i could then cut to size and make space for the wheels to fit...

cut it like a net with enough extra to fill the gap...

but if you decide to do this, bend first and cut to shape after as trying to bend the side of a wedge thats already cut is near impossible to get right (it refuses to bend properly if the side is too short... so just bend a nice L bracket then cut the wedge angle in...

this saves weight in that you dont need some form of attaching method, plus it being bent is probably stronger than any glue would hold it...

only other way i can see would be to cut polycarb to match the exact length and shape of the sides and rear and try fit it in... again small tabs to bend to give you something to screw through or make mini L brackets but this would mean twice the ammount of screws and more weight...

hope this helps
Team Rocket
Trappist 1(4wd grab 'n' lift)
Ton 618 (4wd expanding bot)
Io(4wd flipper)
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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

I usually like L-shaped polycarb as brackets, as I used that method on my first bots. It seems a bit trickier with a mostly enclosed bot with no parallel panels. I've tried several ways of doing it with tabs, and have the papercraft models to prove it. :)

Aside from some very rounded edges, which I wasn't keen on, I was also usually faced the issue of access.

For example; if I add the side panels as tabs which fold from either the top or bottom, then I block off access to the nuts on the hinges. If I make the top, bottom, and sides as one piece, then I have even less access. If I use L-shaped brackets, then I can't access all of them. It seems to be tricky to get right.

I thought I had cracked it with this version, tho. The hinges were supposed to allow the top to flip open, so I could fix it at the back. Lotsa access! :D I didn't do it right, tho, and the hinges are stuck in place between the bolts and the polycarb. Fixable, but I didn't have time or enough sleep to recut it all before AWS.

There are other options, too.. 3D printed brackets would probably work, or even 3D printing everything apart from the top panel. There's probably a way of fixing nuts in place with glue or something, so I don't need access to hold them. Could panels be sewn together using fishing line? That's probably a crap idea. :P
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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Kyro
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Re: Team BLEEP build diary

Post by Kyro »

something like this might help you

https://www.ebay.co.uk/itm/THREADED-INS ... 8235571023

just drill a hole then use soldering iron to sink it into the polycarb... hole is just to stop excess melted plastic coming up through the middle
Team Rocket
Trappist 1(4wd grab 'n' lift)
Ton 618 (4wd expanding bot)
Io(4wd flipper)
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voorsk
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Re: Team BLEEP build diary

Post by voorsk »

Pretty cool!

I just remembered another option that I used while making the front flipper version; HDPE brackets with self-tapping screws. It worked quite well, but cutting HDPE at a small scale was a bit tricky - I had nothing that would hold it in place.

Another option was threaded clip thingies, which I used to use when installing car door speakers (last done to an '88 Nissan Micra about 20 years ago!).

I think it might even be possible to use self-tapping screws in ABS, but I'm not totally sure, and I can't currently print ABS anyway (no enclosure).

I forgot to mention one setback I encountered - the 1S batteries! I attached them in sequence, with a switch between them to kill the flow. When I tried powering the bot up, nothing happened apart from the batteries and their immediate cables getting very warm. I figured I must have a short somewhere, so I went through everything, and undid all the electronics down to the ESC. All my soldering gone, but it still didn't work. :-?

I was gonna appeal for help, but then I encountered the solution by accident. I had a green LED attached to the bot via a resistor, but it was so old and dim that you could barely tell it was there. It ran off of a 2S battery, so I tried it on the 1S combo. It worked!

Well.. sort of. For some reason, I'd put some black heat shrink on the positive side, so I'd actually attached the LED backwards and it shouldn't have worked at all. :o It turned out that the polarity of either the battery wires or the batteries themselves was wrong. I hate crimps, so I'd bought the pico connectors pre-wired. I'd read about some connectors having the polarities reversed while I was choosing a charger, so I guess summat like that has happened. They charge fine.

It's all a bit weird, but I'm sooo glad to be rid of the bulk of a 2S and those frikkin balance charge wires! :)
Team BLEEP Suspicious Houmous / Sprouting Potato / Fermented Melon / Black Carrot
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