Build Reports - Anti-Social - robots

Bot: Anti-Social
Status: Active
Weight: lbs
Builder: Dylan Patterson
dylan@killerbotics.com

The Design and Build Report

My instuctor Bill G. at DCTC told me I could build the frame there. They have a very large amout of welding machines. I'll guess here:

30 arcs
10 oxy-acenaeline(sp)
15 tigs
20 wire feeds

He said I can also order the metal through the school. That gives me a big discount. He also told me to bring in some designs. So I did. I drew them out in Rhino 3d, a 3d redering program.

I am making a LW flipper or lifter. My robot will be made out of 3/4in steel tubing with 16 gauge walls. I am using the ev's for drive. With a 8:1 ratio with 8in wheels. I got my sprockets and pillow blocks from griffco (talk to Jeff) tell him Dylan sent ya. Victors will be the esc's and a rce 220 will be controling my actuator.

Because the Actuator moves so slow i will be gearing it up. I will bolt on a 5 in piece of 12 pitch steel rack. This will be driving a 12 pitch gear on the shaft.

I have yet to decide the Ah rating for my Batteries for the drive. I will be using the same power source for the weapon and drive. I hope that I can afford some hawkers. But that would be spendy.

I am near compleation on my frame. Oh course it took longer that it should have. I hope to finish it tommorow.

Today I tacked the upright supports. It all seems to be going together pretty well it is just one upright that is off by a .25 of an inch.

I did not get to finish my frame today. I am rather annoyed/embarassed about the way my frame looks. The weld are more like repairs. The wall thickness I had was so thin that I would burn through very easily. I had no left over pieces of the same gauge to practice on. Also some of my measurments are off. and when measurement is off the whole this get trashed. Well I'm kinda over doing it, it doesn't look that bad. It still will work and it will be strong but kinda ugly. Oh well, I plan to go with a nice shade of red for the frame.

Right about now in the process I am getting scared. Why you ask? WEIGHT! At the beginning of the process I made all of these weight calcs and came right to 60 but now I keep on thinking about all of the things I forgot.

The main thing is getting the right batteries. I have 2 12v 5 Ah right now. These don't give me enough capacity to run it over 2 min. I just have to bite the bullet and buy some. Last time I bit the bullet I bit too soon. That's why I don't have the right batteries.

I am using 3 EV's. @ for drive and 1 for my weapon. I need to calculate the battery capacity for my robot. The 2 drive ev's pull 60 amps continuous each and 120 at stall. Now for my weapon I will only be turning the motor on for a sec or two for each flip. So I would think that about 20-30 flips for each battle. Now I need to know if there a way to find out how many amps I would be pulling just for that motor?

I just plan on using the batteries I have right now to practice driving. Then before the comp I will purchase the new batts. I would assume it to be around 5th-10th of January.

The main problem is getting the gearbox done for the weapon and then finish the wheel supports on the frame. I need to go to Northern and pick up chain and a #35 45T type B sprocket 3/4 in bore with a keyway. Then I need to buy/order 3 # 35 10-12T 1/2 in bore with keyway. I need to also buy some plastic. To use as a chain tensioner.

Then I need to order my spare motors. I should only need 2 or so. Hoping to win a match. My school gets scrap pieces of Lexan from different plastic companys. I will use .25" lexan for the top and then heat it up and bend it down for sides. For the bottom I either plan on 1/8" lexan and 1/16 steel or just the 1/16 of steel depending on weight of course.
Thank you Eric for helping me. I am only using 2 and 1/2 evs for my lightweight. I say 2 and a half because the ev i'm using for the weapon won't be continuous. Was that just a cheap SLA? That leads me to think that a 7 Ah or 8 Ah would work just fine. I will check before of course.

That's right!

She moves. I only ran at 12v because I don't want it going 15 mph in a confined space (i.e. my mom would get pissed. Also I don't think she wants black skid marks on the kitchen tile. It was great! I used just 1 12v 5 Ah gell cell to drive it. I don't think it was charged. It last for probably 3 min. But that was with flat tires and on carpet.

I finally finished all of my chain problems. It took a while but i got it. I plan on going to fleet farm and picking up more chain and some metal to build my chain tensioners.

A big WELL is needed - After putting it off,I finally weighed it. 55 fricking lbs without armor, new batteries, weapon, gearbox, 16 shaft collars. SO Anti-social is moving up a class to Middle weight. I hope it isn't to late to do this.

I will be adding another ev for the weapon and i will have 30-40 lbs of armor. It will be built like a tank. I wonder if this is a BAD idea.

My only thinking is that my drive train isn't strong enough for a MW. I have a theoretical force of 100lbs. I might change my gear ratio a little. My flipper now has over 500 lbs of force within a half of a sec for the 180 motion. I might want to change my ratio and go for speed. cause the 500lbs is a pushing force and not a staic lift so. Does anyone know a formula for static lifts? I would just assume it is divided by 2.

I have finnaly done somthing right! (Thanks for all of your help Paul Penrose of Team RiverKnights.)

I called Batteries Plus to see if they stocked the 8 Ah monoblocs and they don't. I was doing bargin shopping for them, but nobody stocked them. So I'll have to get them from here and have them shipped from new england.

I ordered sprockets for my gearbox and spares. I also ordered 16 shaft collars and 2 25T sprockets so I can gear it down more. I bought all new chain and put them on. I plan on making just cheap tensioners.

We're ready - more or less - forward to Twin Cities Mech Wars III