Ruination: The Upheaval - Discussion

Post by **Hooray For Lexan** » Tue Jul 26, 2016 6:06 pm

So, I'm actually going to bring Charybdis back for Upheaval!

So, in FRR: Backlash Charybdis honestly kind of sucked. This was for several reasons.

1: I attempted to save weight by making it direct drive. This (a) caused shock loads to be transmitted straight into the motors, causing nasty shit like broken magnets and bend shafts, and (b) meant that to keep the chassis fairly narrow the wheels had to be "offset." This is sometimes called "corner drive," and it's awesome for shell spinners who don't have the weight for 4WD because it makes the robot resist turning better as the wheels have to sideslip, which helps prevent the robot from being spun around by its own counter-torque as it spins up. For exactly the same reasons, it's fucking HORRIBLE for a melty-brain spinner.

2: The wheels sucked. I used 5" "extra-soft" rubber wheels from McMaster, with a 40A durometer, with the goal of having maximum traction. These might have performed okay, albeit with faster wear, on a normal robot, but on Charybdis, because the wheels were spinning super-fast and side-slipping all the time, especially after a hit, they quickly melted and/or ripped their own treads apart. Charybdis's ground clearance was noticeably lower at the end of a match than the start. The soft, but also hot and gummy rubber also did an amazing job of picking up dust from the arena floor, which in practice meant I had almost no traction. The press-fit hubs also tore apart the soft polypropylene wheel cores. Many of Charybdis's numerous failures were because the motor and hub were free-spinning inside the wheel.

3: My control software sucked. To elaborate, I didn't have any "throttle ramp-up" as the bot accelerated. Basically, this meant that each motor was producing its full stall torque of over 100 lbs at the wheel radius whenever I tried to spin up. In addition to screwing over my motors, controllers, wiring, etc, this easily broke the robot's traction and spun the wheels, which would have happened even if my wheels worked. This made spinning up take FOREVER.

This will be fixed in the following ways for the new version:

1: I'm switching to brushless motors. These are sensorless, so they don't have the best startup torque, but they're really powerful, and the effective "gear ratio" of Charybdis is pretty high. It also doesn't have much "friction," so it's easy to get it moving.

2: There's now throttle rampup, although it's pretty aggressive because brushless motors have less startup torque anyway. The new control software also has a cool feature where if it detects that the motors aren't actually spinning, it will automatically reduce throttle. It's not as good as "smart current-limiting" technology, but it will avoid setting stuff on fire in the event of a motor stall.

3: I'm using belt drive now, so the wheels are on the centerline.

4: I've switched to harder polyurethane wheels, and the new hubs are built into the pulleys and have essentially a spline, so they transmit lots of torque.

Post by **Hooray For Lexan** » Tue Jul 26, 2016 6:15 pm

Also: we decided that melties get a +3 traction bonus for spinup purposes, speed+weapon can't be more than 18, and you can add a single armor bonus to the teeth, right?

Post by **Venice Queen** » Tue Jul 26, 2016 6:19 pm

<blockquote class='quote_blockquote'><dl><dt>HotDealsInTexas</dt><dd>Jul 26 2016, 06:15 PM</dd></dl><div>Also: we decided that melties get a +3 traction bonus for spinup purposes, speed+weapon can't be more than 18, and you can add a single armor bonus to the teeth, right?[/quote]those are how the Melty-brain rules are currently set in the re-written rules, so most likely, assuming Kody adopts them for this tournament

Post by **That Kode Guy** » Sat Jul 30, 2016 9:47 pm

Alright, here's the deal.

If I notice people who forfeit pretty much an entire tournament just before this one starts, I'm wiping their spot. I'd prefer to not have a tournament full of forfeits, thanks.

Those of you who don't want to commit to 4 RPs a week... sigh.

The Monsterworks · Post by **The Monsterworks** » Sat Jul 30, 2016 10:00 pm

I agree wholeheartedly with regards to the forfeiting issue. You've got me thinking that I might implement something similar for CBC. We'll see. I'm certainly going to gauge interest as the tournament draws nearer (it's still over two months away).

On another note, I'm still not convinced by the revised melty rules. The intent behind them is great, but having your speed be dependent upon weapon stat has just always seemed... clumsy, and having no discernible control ratio for melties also seems to leave a lot of room for interpretation. I really think that the system that I put forward for CBC, while slightly more complex, evens things out a lot better for melties. In any event, if someone enters a melty, I'll get to pilot it.

Hiicantpk · Post by **Hiicantpk** » Sun Jul 31, 2016 8:05 am

AR9 out, Cirno in.

Y'know. Whenever I make Cirno

Post by **That Kode Guy** » Thu Aug 18, 2016 11:50 am

Okay, so a talk between me and Monsterworks got me thinking about self-damage to bots that have a spinning weapon indirectly attached to their robot (like on a hinge; think something like Archetype and Infrared). I am of the mind that self-damage should really not apply to the main body, since the spinners aren't directly attached to the chassis. Thus, I'd like to propose a different set of self-damage rules for indirectly-attached spinners:

----

Self-damage:

0-4

Post by **Venice Queen** » Thu Aug 18, 2016 1:02 pm

*puts all my weapons on hinges*

Post by **That Kode Guy** » Thu Aug 18, 2016 1:06 pm

<blockquote class='quote_blockquote'><dl><dt>The_Angry_Goat</dt><dd>Aug 18 2016, 01:02 PM</dd></dl><div>*puts all my weapons on hinges*[/quote]Good luck keeping them in play longer than directly attached spinners.

playzooki · Post by **playzooki** » Thu Aug 18, 2016 2:18 pm

I still think they should do some damage to the main body to stop walking death spinners with way too much weapon from winning matches.

Post by **That Kode Guy** » Fri Aug 19, 2016 12:51 am

<blockquote class='quote_blockquote'><dl><dt>playzooki</dt><dd>Aug 18 2016, 02:18 PM</dd></dl><div>I still think they should do some damage to the main body to stop walking death spinners with way too much weapon from winning matches.[/quote]That's what the reduced walker point system will help with.

Post by **Badnik96** » Sat Aug 27, 2016 10:41 pm

asbestosstar your robot is cool and all, but you need four robots for this tournament.

Post by **That Kode Guy** » Sat Aug 27, 2016 10:51 pm

Oh my god...

I'm going to be totally blunt here. The stats are fine, but the robot is completely horrible. Give me one good reason why I should accept that... thing, whatever it is. I can barely make out the shape, you just slapped uncropped images on each view that intersect with it, you didn't even bother to erase the grid planes that are on top of it, and speaking of which, it's not symmetrical in any plane. Plus I don't even know what is going on with the front... wedge, whatever it is. There's just a random cylinder poking up in the middle of the thing for no real reason.

I appreciate that you tried to point out things about the robot in one of the pictures, but... no. Just, no. I cannot accept that, not unless you totally fix all the issues with it.

And yeah, what Badnik said. One robot is not good enough. You need four. And... well, MUCH better quality than what you've displayed so far.

Deleted User · Post by **Deleted User** » Sat Aug 27, 2016 10:55 pm

OK tomorrow I will remove the grid planes and make more pics.

Deleted User · Post by **Deleted User** » Sat Aug 27, 2016 10:56 pm

Oh more bots OK I will.