Team Kaizen Build Diary

[Ocracoke]

I think the ESC just isn't suitable for MWs full stop. It is a neat controller but it is too fragile in terms of the components out of the box but the high gearing will definitely not be helping. Adding in the new gearbox will help but it depends on wherever it is working. Luckily, I still have the second ESC with only the coil missing. I can easily add a new one in to last until the relay controller is built. Might make a video for that.

Yeah, I guess I am a bit dedicated :P. Luckily, the next two events are in Grantham (22nd-23rd June) and Bolton (6th-7th July) so I can feasibly drive back and forth to these events for both days, likely 7am ish starts. My wife will also be coming with me to Grantham, hopefully to pilot Azriel.

[team death]

I use the same ESC in my Heavyweight so I would disagree that it's not suitable for a middleweight.

Your probably not even 60 kg compared to my 110 so it must be something else.

I would look at the ratio first, if it's on the drive or weapon side.

Also driving robots is a bit like driving a car, if you put your boot to the floor and

try pushing others around excessively-somethings going to break.

I use these ESC's because they are affordable and the next step up are scary prices

especially if your just in it for fun rather than a must win frame of mind.

[Ocracoke]

I use the same ESC in my Heavyweight so I would disagree that it's not suitable for a middleweight.

I think you are referring to the 60A dual channel ESC? I am talking about the 40A single channel ESC, which is the next one down from the 60A. The 60A dual channel is a far more reliable controller in my experience but, as you infer, it is how it is used that determines how reliable something is. I knew that the 40A controller was probably not up to the job of handling the F30-150 in Jibril for the Scythe, it was a risk putting it in but at the time, I simply didn't have the money to get a Vyper, which is the "more ideal" controller for this and I was also using the lower duty CIM motor axe mechanism that I'll recycle into Azriel. Of course, now that a custom controller is on the cards, I may not need that much money.

You are correct, Jibril is nowhere near the maximum limit for MWs, it probably clocks in at 34kg with the Scythe (I really do need to get it weighed properly). I also agree that driving it at 100% all the time, ramming into stuff, is going to break something. I am not necessarily in a "must win" frame of mind all of the time but so far, Jibril is just not performing as well as it should be able to. I want to do well in the MW championships in November. I think the drive ESC will be reliable enough to do so but the axe controller needs work.

[team death]

In that case you are probably correct, I had two of those blow on my featherweight drive

they seemed fine when not under load but they are poor performers compared to the 60 ESC.

You might be better off with a couple of solid state 100 amp relays, I assume you are not

bothered about controlling the scythe speed-quicker the better?.

[Ocracoke]

I was talking with Gareth (of Trolley Rage) about this and he suggested something very similar. In terms of an controller for axes, I guess you would want it to be a on-off affair to get maximum oomph on the swing rather than have any finesse in the controls of it. I've been putting a wiring diagram together for a controller using relays but I found how to wire up reversing solenoids last night so I may need to revise it.

[Ocracoke]

So the parts for the two stage reduction have arrived and I'll be cutting up the HDPE for both the gearbox and Azriel tonight. It did however strike me that I had forgotten the bearings! Bleh, they are on order now but with out them, I can't finish the gearbox off beyond marking out where the shafts go on each side.

I guess I can occupy the time waiting for delivery with building Azriel and fixing the ESC yet again. I've also got Ikari to rebuild with a 70W brushless motor for a spinner drive this time. Oh, and the BotFest arena rebuild. Busy busy

[Ocracoke]

Jibril
So the gearbox sides have been cut and the gears are on the shaft for Jibril but I've yet to make any head way in actually building it. Given the now tight timelines to RL Grantham, I may not have this ready by then, which would be a massive pain. I'll get the ESC fixed during this week anyway but it is touch and go as wherever the two stage box will be ready by Grantham or Bolton.

Azriel
I've finally got underway with Azriel! I've decided to scale down Jibril's design to FW for this one which whilst I am not a fan of doing this, it allows me to try out a few things on a smaller scale first before committing to the change on the bigger robot. The body has already been made and all the electronics I have, it just needs putting into the body. I aim to have it ready for Grantham and then have it upgraded by RoboDojo if I am able to go.

JPEG_20190615_205920.jpg

[Ocracoke]

Azriel
After finding a few moments to concentrate on this one, I've got it rolling. It isn't The Honey Badger quick but it is quite controllable as a result. Thanks to having the wiring loom, motors and the wheels from Kaizen, it was a simple install. Nothing is bolted down yet though, I need to extend the loom for the axe which I'll work on tomorrow. Once that is done, a lid installed, LEDs added and a removable link hole, that is it, it'll go to RL Grantham with Jibril. I'll also put a wedge on the front rather than the blocky look it has now.

JPEG_20190617_192420.jpg

[McMullet]

Nice going! What's the drivetrain made up of, the motors look like something a bit nicer than drills...

More importantly, is it also going to be pink?

[Ocracoke]

They are Gimson 13.7:1 motors (https://gimsonrobotics.co.uk/categor...tary-gearmotor). Coupled with 775 motors, they are a solid, if slightly expensive, package. These ones are quite worn as they were being used in the Middleweight class but they work well enough. Even on 4S LiFe, they are powerful enough... for now :P

Azriel really is a bot from spares. The only "new" bits on it are the HDPE body parts, the rest was recycled from other bots, mostly Kazien but some Shu! and The Honey Badger too. Think it's cost me about £40 in "new" parts.

Nah, got a different, garish, colour in mind for this one. Might not have it painted by RL Grantham mind. If I can make to RoboDojo (bearing in mind I'll be at EXR Bolton as well, so potentially spinners galore), it'll definitely be painted by then.

[McMullet]

Nice... Looking forward to seeing it finished!

[Ocracoke]

As a general inquiry, what ratio do folks run their axes at these days? For RL Grantham, Azriel will use the same 3:1 setup that Kaizen used last year with the CIM motor which in testing has been fairly rapid but I'd like it to be able to self right and reasonably effective at making an impression one way or another. I think I can add some small counterweights to help.

The bearings for the two stage box for Jibril has arrived. However, I've come to the decision that I won't have it ready for RL Grantham and if I try, I'll end up rushing it and probably end up making it worse. I am going to therefore get the ESC mended for the event and pretty much leave it there. I need the metal axe blade from the plastic Scythe for Azriel so the big Scythe on Jibril will remain where it is and once Grantham is out of the way, I can focus during the two week window for EXR Bolton, which I am hoping family is coming along to see so I really do want it working by then.

[team death]

I don't have a axe weapon but I do have some knowledge of cim motors and ratios.

You would never be able to self right with such a ratio of 3:1, I would use a minimum

of 8:1 and you will be suprised how little effect this has on weapon speed but does

increase the power greatly.

Looking at your design it may be possible to attach a chest expanding spring to the axe or

scythe head to help on the return stroke-they have a pull of over 5kg so might assist with

the SRIMEX.

[Ocracoke]

Thanks for the advice Colin. With the gear ratios on Jibril going to 15.75:1, I suspect that'll help a lot anyway but the spring idea isn't a bad idea, I think the season 2 version of Bumblebot used something like that?

Azriel
It is as finished as it is ever going to be for RL Grantham! Had a small hiccup with the axe ESC but it turned out to be a dodgy terminal connection. Anyway, a picture of Azriel 0.9! (Apologies for the black background, it was photographed on a black carpet and it would have looked weird with a white background.)

azriel_0.9.jpg

Armour: 15mm HDPE, 6mm polycarbonate
Power: 4S LiFe batteries
Drive: 2x 13.7:1 Gimson motors
Weapon: Axe powered by a CIM motor going through a 3:1 gear ratio
Weight: 11.1kg

There are elements I want to work on, like the exposed wheels and the axe gearing as discussed above (and of course, it is not painted in a suitably bright colour) but it'll run for Grantham in this configuration. There was a discussion on the MW Discord channel about wherever we'd run FW minibots with the MWs at the event, not sure if that is going ahead. I wonder if I'd be OK running this with Jibril... maybe. But heck, for a robot that cost me about ~£50 in new parts and a lot of recycling, I'll take it.

I found a 3S LiFe battery so if I can get it charged, I'll put that in Azriel for 5S in series for the extra oomph.

Now I need to work on Jibril.

[McMullet]

Looking great! Well done on using most of the mass budget.

I found a 3S LiFe battery so if I can get it charged, I'll put that in Azriel for 5S in series for the extra oomph.

I may be missing something there, but what's that going with to make 5s? Presumably not the 4s, because that would make 7s?