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Author Topic: AmbiSinister  (Read 5193 times)

MDBuswell

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AmbiSinister
« on: August 13, 2015, 01:40:02 pm »
Whelp, I've been lurking on these forums and the old Delphi forums for years. Since I've actually been employed in the past few years in a job that pays me more than the bare minimums, I guess it's time to hop into the sport I've wanted to join going on a solid decade now.

To start this off, I have a parts list of components for an Antweight shell spinner. I manage a parts department where we sell arborist and landscaping supplies and came across a large pulley. I checked into some sizing on the typical components and figure I can squeeze the guts inside this thing and figured it'd be fun to build. Will it implode in one hit? Most likely, but it should look spectacular in that destruction as any other!

I plan on putting in a FingerTech order today or tonight when I get around to it. Lunch may not be enough time to pull out the wallet, and the boss likes to poke his head out. But I do have a question for you gents. The design that I have in my head currently would utilize a 3/8" bolt as the center shaft. I planned on making it a dead shaft and having a single bearing attach to the top of the spinner and let it ride on that. To that end, my thoughts were to use nuts to capture the bearing. I assume that may be a heavy way of doing things, and that it also might be silly to use a single bearing to have the shell ride on. I was hoping to have weight to place small pieces of plastic on some of the edges to keep the shell from twisting too drastically. My idea was to place a wheel on the weapon motor to drive the shell through friction. But the bolt would need essentially 3 nuts, one to place against the head to locate it on the chassis and two to capture the bearing. That seems like more weight than I can budget for it, though I'm not positive how much leeway I'll have to work with currently. I have to modify the pulley first before I can figure that part out. Though with basic online weigh calcs, I seem to have several ounces to play with after all is said and done.

So the main questions are, should I use a live axle so that I can have two bearings taking the forces? And would 3/8" be large enough for that shaft, or am I looking to have it bent in a matter of minutes? Could I get away with using a thin spacer between the shell and frame made from plastic?

Oh, for some hard numbers, the shell is roughly 5" in diameter and about an inch tall. I'll be cutting out most of the hub section. The plan is to buy a good steel bar and bend it 90 degrees at the ends to attach it to the shell and this will house the bearing and attach to the shaft. Shell is largely for looks and added weight at the edges for KE. Oh, and some semblance of armor. I haven't chosen a weapon motor yet, though I assume I want to spin slower rather than faster. I don't know if 6K is too high to shoot for. I've got a better idea of things with bigger bots, but haven't paid my attention to ants and beetles over the years.
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

Badnik96

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Re: AmbiSinister
« Reply #1 on: August 13, 2015, 06:29:25 pm »
Honestly I'd go with a dead shaft, easier to mount and you don't have to waste weight putting in a retaining wall for the electronics.


Also, check out this thread here:
http://battlebots.forumotion.com/t675-camden-s-confoundations

About as detailed a report for a 1lb shell spinner as you can get.

What events are you planning on bringing it to?

Good luck man!
TEAM IGNITION
FireArrow (Antweight) 23-11
Nocturne (Beetleweight) 5-10 (Retired)
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Pennbots 2014 and Bot Blast 2014 antweight champion. Bot Blast 2013 Best Driver and antweight third place.

MDBuswell

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Re: AmbiSinister
« Reply #2 on: August 13, 2015, 06:46:26 pm »
Thanks for the link! I spent a couple of nights attempting to hunt down something with a build report on a Shell spinner in the antweight class. I looked over Colsonbot a bunch and found mentions of others, but not a full run down. I never knew that forum existed.

Yeah, the more I think about it, dead shaft with a spacer is probably the easiest way to go with it. I'll check out the axle spacers we have at work tomorrow because I think we might have one that'd be small enough to work. Of course the main thing is getting the rest up and going. I assume I'm going to he pushing it on weight and have to grab it from places, but I'll cross that bridge when I come to it. Having everything but the spacer and bolts I've got like 3 ounces to spare. I'm thinking it's running a bit close to the max, but I also may be over weighing the shell. I'm going to see if I can cut the thing down tonight and then weigh it to see if this is even feasible or if I should hop back to square one. :)

The initial event would be the one they are thinking of starting up in Boston. It grew from a Facebook post and I'm hoping it takes off and I'll be able to fight it there. I live about 45 minutes south of the city, so it'll be an easy commute. From there, I hope to make Motorama this year because I am in desperate need of a vacation. I've got plans for bigger bots as well so that'll go great with having the extra time after this. After that, who knows. Mainly depends on what time I can sneak off from work, and how well I can keep the little guys running!
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

zacodonnell

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Re: AmbiSinister
« Reply #3 on: August 13, 2015, 08:28:12 pm »
I recommend a dead shaft too. I use it on my shell spinners Tripolar, Steel Shadow, Tetanus, and now Triggo. 3/8" bolt for a shaft should be way beefy for an antweight. I'd bet you could get away with a good .25" grade 8 bolt but the bearings and hub setup you're planning might not work at that size.

I look forward to seeing what you come up with at Motorama. I guess Central PA in February can still count as a vacation from the Boston area... It's been working for the Canadians for years :)

-Zac

MDBuswell

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Re: AmbiSinister
« Reply #4 on: August 13, 2015, 08:37:50 pm »
Yeah, as I read through the linked post I realized I may be over engineering things. I don't have a bearing bought yet, nor a system in place, so it's still modifiable. I'm going to look into dropping to a .25" shaft if I think I need to save some weight. I've got the pulley to be turned into the shell, and I've got 90% of the bot ordered. I'll grab the rest of the stuff and get it all on a scale before I lock in some of the last parts and just how much I'll have to modify the shell and such. I'm thinking I'm going to be up against the wall with weight on this thing already, but that's half the fun. So many places to drop a bit here and there!

Working in the landscaping business I find I have two windows for vacations unless we hire another person to work in my department. 1) Dead of summer when grass ain't growing because it's hot without rain. 2) The dead of winter, when nothings growing because it's winter. We do plow parts, but unless we get another year like this past one, a week off shouldn't hurt. But spring and fall are just too busy for a single person to work the counter a week by themselves.
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #5 on: August 20, 2015, 10:10:04 am »
Haven't had a great deal of time the past couple nights to do much. Between traffic and the fact that people keep seeming to be on vacation at the job means later nights than normal. BUT, I do now have a pile of parts that may or may not be able to become a bot. I'm hoping tonight to be able to go home and start splitting the pulley apart and seeing the weight I have to work with. Might need a stop at Harbor Freight to get a new drill that my Dad broke a couple weeks ago and might snag a scale that will actually give me more accurate weight for this thing.

https://drive.google.com/file/d/0B_IPn7qcHqNOOXBUZzJzdHNYUXc/view?usp=sharing
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

zacodonnell

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Re: AmbiSinister
« Reply #6 on: August 20, 2015, 06:26:33 pm »
A decent scale pays for itself pretty quickly. If it saves you one "oh crap, that isn't what it weighed at MY house!" at an event it was worth it.

-Zac

Travis7s

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Re: AmbiSinister
« Reply #7 on: August 22, 2015, 11:36:51 am »
If you have a uncertain about your scale, bring a consistent object like a wrench or something to a calibrated scale at the post office and have it weighed. Then you can use that object to 'calibrate' your scale to see how far off it is.

MDBuswell

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Re: AmbiSinister
« Reply #8 on: August 24, 2015, 02:30:37 pm »
Good call. I'll have to get a "calibration tool" to keep with me. My Mom actually had a spare kitchen scale that she was given as a test model from the company she works with, so I have a scale for up to 11lbs. It'll work for this project and I'll pick up a good scale for up to 30 pounds, because that's currently as large as I plan on building.

Oh, and I got the shell split by the guy at work. I need to clean it up, but it looks good. Problem is, it weighs 11oz. Definitely more than I thought it would. So now I have to see where I can cut out some weight and trim some things down. I can take material out of the shell, except I can't promise myself to keep it balanced enough to spin it up afterwards. XD So I'm looking at my options.
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #9 on: September 23, 2015, 09:14:09 am »
Been working on the little guy off and on. I'll be honest, a couple times I had to order parts and instead of getting things ready for said new parts, I went to other projects. Namely, football. Over the weekend, I got a really really bad contusion on my left knee and so had to take things easy. After a couple hours of on again off again icing, I went to the basement. I think I rebuilt the framework for this bot a dozen times now. This worked, this didn't, went to try this, oops....

But, I think I have finally figured out a final solution to get it all to fit and work inside the bot as I want and just need to remake most of it again to get it to have the bolt holes where I really need them. I had the weapon motor held on by 2 bolts and the center shaft isn't very centered. :p I've got to get a picture of the new stanchion that holds the weapon motor as it's a different piece of aluminum framing. And I need to pick up heavier duty velcro. Outside of that, I think I've got a plan that'll actually work. And in for this project, the constant rebuilding didn't really cost anything but a few minutes where it's so small and the materials I had to buy bulk anyways. Works out, right?

The shell will be the last piece I get working, but I'm kinda hoping to have the rest of it pretty much ready to rock and roll soon. I've had the pieces bolted together and moving. Now it's just a matter of getting the final frame pieces, probably making a spare or two, and putting the whole shebang together minus the shell. Then I'll see what kind of weight I have to play with. Judging by my scale and just laying the pieces that aren't bolted yet on, I'd have quite a few ounces to play with. That makes me happy because that means I can add some nice teeth to this spinner and hopefully make it actually deal some damage.

https://drive.google.com/file/d/0B_IPn7qcHqNOd3UwRWRkclVmNDg/view?usp=sharing

https://drive.google.com/file/d/0B_IPn7qcHqNONGVoX2RkRTZPNlE/view?usp=sharing

https://drive.google.com/file/d/0B_IPn7qcHqNOcXNhS2lpSk9UZjQ/view?usp=sharing
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #10 on: September 25, 2015, 12:38:43 pm »
Last night was pretty productive. Using 90% cut off wheel and 10% electric drill I'm forbidden to take apart, AmbiSinister has not only been constructed, but SPUN UP!

https://drive.google.com/file/d/0B_IPn7qcHqNON1pUVzdMVzdoWnc/view?usp=sharing

Ok, so the shell hasn't been made yet so it was just the motor spinning, but it's a proof that I can actually get the thing to do what I was hoping it would do without blowing up. And it didn't blow up! Now I just have to get used to the tiny wiring that my sausage fingers aren't adept at wrangling around. That's the last major thing with the chassis, getting it wired up. Once I have that complete, I can move on to figuring out my weight and construction of the shell. I have a small steel mixing bowl I'm thinking of using. Current plan is to cut the bottom off, flip it upside down and get a piece of square steel to run side to side. The square steel will be the teeth and mount point in one, and attached to the shell. That way the shell is there mostly there for weight. The arm does all the real work and takes the bigger beating.

Tonight I'm stopping at the local electronics/robotics store to pick up the proper tools for working with the tiny wires here. Then I hope to have it all velcro'd and zip tied down tonight. Get it locked down so I can see the final weight and get some driving experience in. Once I have the little guy mobile I can see how horrible I control it. Then the final design for the shell gets started and once it's all complete, I can actually give it a full test. Little bits!

https://drive.google.com/file/d/0B_IPn7qcHqNOdk1qOENjNEV0dE0/view?usp=sharing

https://drive.google.com/file/d/0B_IPn7qcHqNOQ0pTOVZHcVNwaVE/view?usp=sharing

https://drive.google.com/file/d/0B_IPn7qcHqNObkp1c2tBSElSaXc/view?usp=sharing
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #11 on: October 11, 2015, 10:20:50 pm »
Ambisinister - [adjective] Clumsy or Unskillful with both hands.

I can honestly say that it fulfilled that to a T.

I showed up late to the event, and luckily wasn't so late that I wasn't allowed to fight. So did my best getting it together and good to go. Unfortunately, the battery never got charged beforehand, so with tightening the nuts holding the shell on too tightly, the battery didn't last the first 2 minute fight. Whoops. Live and learn, next time find more minutes prior to the event to have it packed and ready to roll. Second and third fights went similarly. 2 I put the throttle up on the spinner and it isn't balanced nearly enough so it pulled a mauler and ended up on my head. The forces pulled the weapon motor wires out from under the zip tie and cut them. Fuller battery, still lost. Third fight, I spun up slower and it was looking good, except I couldn't get the drive to really work. I'm still not positive what made it so difficult to move, but whatever it was, I ended up drifting into the wall, smashed myself back onto the shell and the nut holding the wheel to spin the shell came off so I lost weapon. Dead in the water. Darn. Last fight, I reversed the rotation of the motor so it'd help hold the wheel on and began the fight spinning up slowly. Got up to a decent speed and began moving slowly and had enough control to move forward into a floor seam. Hit it and flipped. HOWEVER, kept the weapon alive and got myself back onto my feet. Mild Success! The other bot and I converged slowly, neither at 100%. Gave it a couple decent hits and he sat dead in the water. I guess I got a decent shot on his battery. Tap out.

So, first event I went 1-3 with an untested bot built with scarp materials and a drill and angle grinder. Can't complain too much about that. There will be upgrades. I had severe doubts about the bowl holding up prior to the fight. But hitting the wall at 70% power and not having the tooth shred itself to pieces was very nice to see. Should have had a bit more confidence. Thanks to all the builders that made the MassDestruction event. Was a phenomenal time. Glad I got to talk to a couple of you and learn a ton. Hope to keep at it and be there for the next event as well. Though, hopefully more prepared.
« Last Edit: October 11, 2015, 10:22:21 pm by MDBuswell »
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #12 on: December 27, 2015, 09:48:09 pm »
Well, I wasn't able to make the second MASSDestruction event due to work. The biggest show of the year for us swung around in December instead of January because they got tired of fighting the snow. Which made me a very sad little guy.

But it has given me some time to play around with AutoCad Fusion 360. It has been one hell of a learning curve and I've been struggling with a bunch of things. But I think I finally got most of it under control and snapped my initial upgrade ideas together. And I didn't like them. So I started over (much easier to do on CAD than physical iterations) and revised me initial thoughts. And I'm pretty happy with what I've figured out. Will it work? Not a clue! But it's amazing to have 1:1 diagrams to put on the plates to cut and drill the holes. Things might actually line up this time and the bot might work as it's supposed to!

Still sticking with the FBS. Using the same shell though I do want to switch to a belt drive instead of the friction drive. I liked the friction drive, and may still run with it, but I just feel like designing a wheel to fit on top might be more difficult than slapping on a couple pulleys and a belt. But we'll see how it all goes together the first time and what seems to work before I make the final call on that. Going to 4WD instead of the two wheels so I'm not high centering myself and unable to drive with any surety when up to speed. Hoping to have a better platform and better performance. Shooting for a slower speed as I'm not sure I really need to be able to move around all that fast.  ???

So, here's the CAD as they sit. See if the final product looks anything like this.

Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

MDBuswell

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Re: AmbiSinister
« Reply #13 on: January 09, 2016, 09:42:00 pm »
Whelp, learning to CAD definitely made the construction much easier this time around. I cut the Garolite out and have most of the bot screwed together at the moment. I actually put the battery in place and ran it around a little bit to see how it all worked. Love it.

I do have a couple questions on it. I have the shell from last time and it's pretty much ready to rock. I picked up two bushings instead of the bearing I used last time. It'll be a bunch more space on the shaft, so it'll hopefully steady the shell more. The 4WD should help too. But I'm still kinda stuck as to if I'm doing it right. It seems to wobble a bit more than I was hoping. Is there a better way to mount the shell to a dead shaft than using bushings attached to the shell and centered with nuts? The dead shaft is a 1/4" bolt. Also regarding the weapon is attaching the wheel to the weapon drive motor. I have the motor on the back of the bot and it's within decent distance of the shell. Last time I used a foam wheel that I pushed a nut in the middle to give it some centering and just sandwiched it on the prop adapter. It had a tendency of unbolting itself and disabling my weapon. Is there an adapter out there that I could use to mount a tire to a prop adapter or the motor itself?
http://www.hobbyking.com/hobbyking/store/__66423__Multistar_V2_2206_2150KV_Motor_The_34_Baby_Beast_34_V2_.html That's my motor.


https://drive.google.com/file/d/0B_IPn7qcHqNOVGFTNElueW9peHc/view?usp=sharing
https://drive.google.com/file/d/0B_IPn7qcHqNObDNvTExKYWJvZ3c/view?usp=sharing
https://drive.google.com/file/d/0B_IPn7qcHqNOOGU0SHhmZG1Uak0/view?usp=sharing
https://drive.google.com/file/d/0B_IPn7qcHqNOc0lSdGUyUkN6R3c/view?usp=sharing

« Last Edit: January 09, 2016, 09:43:48 pm by MDBuswell »
Featherweight in progress - Gallowglass - Team Damned by Design
Antweight - AmbiSinister - Team Damned by Design

zacodonnell

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Re: AmbiSinister
« Reply #14 on: January 10, 2016, 10:05:07 pm »
Are you running the bushings on the threaded part of the bolt? If you are, it is likely well under the diameter the bushing expects, which is causing some extra wobble.  Even the shoulder on a normal bolt isn't usually the right diameter.  Maybe look into shoulder bolts, as they have a precision surface for bearings to ride on. Something like this one from mcmaster might work for you (I just guessed on the length, many options available)
http://www.mcmaster.com/#91259a106/=10mn00w

As for mounting a wheel to a shaft, depending on what kind of wheel you're using, you might be able to use the fingertech blade hub:
http://www.fingertechrobotics.com/proddetail.php?prod=ft-blade-hub

Or possibly a snap hub (which you can get with a wheel that fits well probably)
http://www.fingertechrobotics.com/proddetail.php?prod=ft-snap-hubs

Get the 3mm size and drill it out to 1/8". That should work well for you.

I look forward to seeing this in person some day.

-Zac