Author Topic: Bone Dead Robotics  (Read 51871 times)

zacodonnell

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Re: Bone Dead Robotics
« Reply #120 on: July 10, 2015, 09:07:25 am »
You could do what I'm doing on the friction roller in CounterStryker - put a bearing between the motor and the friction roller. Not sure if the shaft sticks out far enough for that.

Also, on the worn out friction roller make sure to remove the hub from it. You should be able to reuse it if you get another wheel. You just need to drill a hole down through the center of the wheel, then push the hub into the bore of it with a bench vise so that the hole in the hub lines up with the hole you made in the wheel. To take the hub out you need to pull the set screw all the way out though.  It's good to have a spare. You can get the wheels at RMP or mcmaster.

-Zac

BranYoung

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Re: Bone Dead Robotics
« Reply #121 on: July 11, 2015, 11:54:05 am »
Yea the shaft no longer has room on it for a bearing to squeeze in. For next year, I might try to indirectly drive the weapon with a pulley to the friction roller much like how you did on Scurrie.

Yep, that's the plan. I already pressed it out. I actually used that same mounting technique of drilling through the wheel for wheel mounting on the antweight. Works like a charm.

BranYoung

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Re: Bone Dead Robotics
« Reply #122 on: July 19, 2015, 01:28:33 pm »
Well Bot Blast was quite an experience.

CATAPULT has still got some teething to do.

First: IT SPINS UP! While I don't have much video of it doing so, it spun up CONSISTENTLY. It takes a bit too long to spin up though, especially in the fairly tight box. Basically, if you are a moderately fast wedge, it was going to take a beating.

And it did.

It's first fight was against Landshark, a wedgebot. He rushed CATAPULT and threw it into the wall 3 times before the weapon could get up to speed. Fortunately though, it did get up to speed and got a great shot on the left drive wheel. Because his robot has Banebot wheels, the wheels cracked and the force was transmitted to the gearboxes and manage to shatter a gear in the gearbox rendering him with only a single-wheel of drive. Unfortunately, the use of set screw collars backfired on CATAPULT and the shell fully left the chassis with shaft still on it! The base was working though and the weapon motor was still humming. Landshark wins by Judges' Decision.

The second fight was against Chibi Blackout, a exceptionally well-made robot built by Don Doerfler. It was basically my worst nightmare with a vertical spinning drum, wedges on the front, and a very quick drivetrain. As a result, there was great damage. For the first few seconds he pinned me against the wall and dug in with the drum. Once CATAPULT got up to speed it delivered a good hit or two before Blackout managed to get a shot which bent the shell back into the chassis and basically seized the weapon system. He then proceeded to further mangle the shell, bending all but one of the teeth into horrific shapes. After the match, I discovered the shell was wrecked, but the main chassis and systems were almost totally unharmed. With a great deal of modifications to the shell and maybe 4WD for better drive, CATAPULT should be ready to go next year!










El Destructo was not really disappointing, but not quite satisfactory either.

In its first match, ED faced a wedgebot named Sparty Mini and won by virtue of knocking one of its wheels off. Despite this, ED's drive has been less than reliable. It seemed to be only hobbling around more so than actually maneuvering.

Its second match was against the eventual second place robot Dominant Mode. There were two main issues with it. While the weapon speed was comparable to Dominant Mode, the shaft collar on the left side fell off which made it useless after maybe 2 impacts. The persistent issue of driving weakness was evident when Dominant Mode simply swung around the back and proceeded to tear off the backplate. As a result of the innards falling out, the match was called and Dominant Mode was victorious.

The third and final match pitted ED against Chibi Knockout, designed very similar to Blackout, with a very similar result. After a shot or two being exchanged, he managed to very easily swing over and hit the wheels, effectively seizing the gearboxes on both wheels and rendering it motionless. El Destructo lost and was out of the tournament.

Play 'n Krazy v2, while it wasn't entered, was the most successful. It competed in a mock battle against 2 rc cars and Regift, the birthday present. It was glorious. I also found the part about attacking the robot covered in 'Happy Birthday' wrapping ironic because of how it was birthday the day before. It fought one more time in the Beetleweight Rumble where it proceeded to rip up battle-damaged beetles with glee. Unfortunately, I didn't check to see if the battery was charged so the weapon died in the last 30 seconds and then lost drive right at the buzzer. It was much fun. If it can get in at the right weight, it seems to be a very promising creation. I don't know what it is, but the soul of PK just never ceases to please me.

BranYoung

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Re: Bone Dead Robotics
« Reply #123 on: July 20, 2015, 10:06:19 am »
Alright, so at Bot Blast, Chibi Knockout and Dominant Mode managed to take a few good chunks out of El Destructo's weapon. At this point, the weapon bar's threads for the screws have been blasted so that they can no longer retain screws. As a result, I've decided to re-re-build ED with a better drum.

My first idea was to use a strategy similar to Grande Tambor with a motor shoved inside a drum and then using a screw and bushing on the other side to support it. I am also planning to experiment with 22:2:1 Silver Sparks in a Beetleweight. I remember Aaron Fan using them in In the Margins at Motorama. According to the Tentacle Torque Calculator, if I run them on 3s and have 2in wheels it will go 5mph. Not very quick, but most of the weight would go into the structure and drum. I'm hoping to have a 2.75" OD x 5.5" wide drum with a 7075 body and either small S7 inserts or replaceble screw design like the Wetas. Instead of the classic 1/2" UHMW, I might try to go with 7075 AL frame that are maybe 0.375" thick.

The second idea was to keep the same drum design as the previous (in-drum motor mounting) only the drum is 4.5" wide instead to accommodate for 1000RPM motor drive. The greater drive will allow for better speed.

The third idea was to use a conventional pulley to the weapon to save the weapon motor, motor is protected within the main frame, drum is 2.75" OD x 5.5" wide and is styled almost identically to the conventional Weta beater bar; pulley on the side, gap in the center, replaceable screw teeth, pressed in needle-bearing, etc. The drive would be the aforementioned Spark motors to allow for greater structural integrity (the aforementioned 7075 frame rails)

The fourth idea is basically what ED was like before with UHMW frame rails, 1000RPM motors for drive, but the 2.75"OD v 5.5" wide drum to decrease the overall footprint of the robot (and hopefully keep it on weight!)

Koolaid64

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Re: Bone Dead Robotics
« Reply #124 on: July 20, 2015, 03:34:53 pm »
just get longer screws and put a nut on the other side

BranYoung

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Re: Bone Dead Robotics
« Reply #125 on: July 26, 2015, 08:59:44 am »


Hope this guy can accompany PK for Franklin

BranYoung

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Re: Bone Dead Robotics
« Reply #126 on: July 30, 2015, 09:53:28 am »
So this is a top view of the CAD of ED's re-re-build. The idea of this design was to make the robot as dense as possible while still maintaining use of this large beater bar. To do this, I had the thought of simply placing standoffs around the basic chassis. The problem I notice with this design is that the standoffs, which will need to absorb the largest amount of energy, are being held on by nothing more than perhaps two of these screws: http://www.homedepot.com/p/Grip-Rite-8-x-1-5-8-in…/100112584 and the Garolite/Lexan plates. While the screws aren't bad, the 1/4" frame walls that it bolts into may be susceptible. As a result, I most likely will have to beef that up to 1/2", but I still fear whether this type of attachment would still be strong enough to survive the insanely powerful beetles of today.
In addition, the plan is to use Silver Sparks for drive. There is a very clear fact about Sparks in beetles: They need support. As a result, there are two dominant paths to go about it (or you could combine them for a third): using a simple pulley to create a indirect drive system from the pulley to the wheel. The benefit of this is that the wheel could be moved forward closer to the weapon which can allow for improved turning. However, if a horizontal spinner was to get a lucky shot on its side (DDT v Cyclone at Bot Blast 2015) then the motor or its belt could be wrekt. The other path is to directly drive the wheel from the motor, but to surround it with protection such as the 1/8" UHMW ring shown in the CAD. While it doesn't allow the movement of wheels, it does protect it better from the direct shot of a horizontal spinner (of which there are a LOT thanks to Ray's many robots). To test the adverse effect of not moving the wheels, I created a test bed to see how negatively it affects the drive. With 2.5" wheels, it drove fairly well on 3s so it should be acceptable on 4s. As a result, I may stick with the direct drive and just add wheel guards.




Thoughts?

BranYoung

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Re: Bone Dead Robotics
« Reply #127 on: January 06, 2016, 10:56:17 am »
Woah its been a minute since I did stuff on here! I made a proper website to look more legit even though we are all still kids playing with toys  ;).

Anyway, here's a link to the site: teambonedead.com. All robot stuff is under the "Combat Robots" tab and is linked to a Blogger. Have a look if you can!

RevRobots

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Re: Bone Dead Robotics
« Reply #128 on: January 29, 2016, 06:54:20 pm »
Really expensive toys. ;)

Adam
Revelation Robotics