Last Week and Next Week (PA Bot Blast and Otakon)

Finally, a weekend where I am not rushing about to see new places or compete against other sentient beings. However I have stuffs to prepare for next week so after 7 hours of straight soldering, I elect to type up a post while I am still on a solder fume high (no not really).

Made the drive from Maryland to Pennsylvania for my first ever PA Bot Blast event! Driving up to Harrisburg in the wee hours of the morning but when I started up the road to Bloomsburg things sudden looked very hilly and untouched. Towns built into the valleys of the massive hills, which were covered with trees; to be honest I felt like I was in a northeastern Costa Rica. 7 halves hours later I arrived at the Columbia Mall and prepared to set up.

I brought P150, DDT, and Cake to represent the south. I hadn't really run these robots since April, so I assumed they were in working order. Boy was I in for disappointment. P150 and DDT both went 1W:2L for seemingly dumb reasons. They both lost wheels in their first matches. P150's was removed by hedgehog's angled cutter (and P150's poor control), and DDT's seem to have fallen off by chance (when Fangus and DDT hit, he popped the belt off the pulley, jamming the blade and spinning the robot, which threw the wheel off. If Fangus was the cause, my shaft would be missing). They then proceeded to defeat robots in their expected fashion only to lose again disappointingly. Some additional thought needs to be put into these robots.

Cake made a wonderful representation! 4 wins and 2 losses, both losses caused by One Fierce Lawn Boy from Fierce Robots. Every match ending up in KO. Videos below.







The money shot of the event. The final hit between Ripto and Cake in the loser's finals match resulted in Ripto being lodged between the lexan and the outer barrier. Ouch.



Jeremy ran a very professional event. Organized procedures, match listings, and even had clarifications for the grey areas of robotic combat. Needless to say, I'll be returning if I am in the area again!

PA Bot Blast 2011 Album



Next week will be Otakon, the largely anime convention in the Baltimore area. Now, I am not a huge fan of anime, but I do like to create. I had my Tony Stark, Iron Man costume shipped up to me during Independence Day break so I could work on it. A few upgrades ensued.

First I decided to add a blue tint to my LEDs. Feeling resourceful, I merely took a marker and drew on the outer surface. Nothing fancy.



The other upgrades were all for my sanity. I redid the wiring to be much more robust and clean. At Dragon Con, I had several problems with connections breaking and repairs required. This time, all solder joints were solid, shrinkwrapped, and glued.

Supermassive Updates

I neglected updating the blog for awhile due to life, but I promise this post has some good content. First, the summary:

• P0w3r Drive
• PA Bot Blast Preparations

Last time I assembled the endcaps to find they were wobbly by not-so infinitesimal amounts. Did I re-machine them? You bet. But this time I implemented a different technique.

You might recall, the technique I have been using to machine the endcaps was to first rough cut a disk of aluminum on the waterjet and then turn the parts on the lathe using a socket cap bolt through the center. I believed the source of the issue same from wiggle room between the starting bore in the waterjet plate and the OD of the bolt (since drill bits increase in discrete amounts not necessarily tuned to bold diameters).

So this time, I decided to apply some angular principles of self-centering. I angled the bore by using a countersink bit. Furthermore, I grabbed the appropriate flat screws for the duty and a hexagonal standoff for the opposite end. It basically worked like V-groove stands for machining tubes. The round object is guaranteed to sit in the center of the groove. Works similarly for the conical shape. This method returned a much truer endcap, and validates the technique.


Also, automatic feeds are AMAZING. Almost a mirror finish. Never before have I turned such a smooth part.




I was only able to finish one end before the term ended, so there is no way I will be able to test the wheelmotor this summer. What I can do, is wind the stator. More on that in about 12-14 weeks.

In other news, I'm finally going to fight robots again! Dreadfully Wicked Robots is hosting PA Bot Blast in the Bloomsberg Mall. Features robots from 150 grams to 6 pounds. Heavens know I don't have a 6lber, but I do have the insect fleet.

I will be taking DDT, Cake, and P150.

Wait, p150? isn't he dead? Yeah, kind of. But he can be rebuilt... better... faster... stronger...


...and more carbon-y. Seriously, lets use some of these resources I have at the Invention Studio to make some grade-A bots. P150v4 uses the old 7.4, 300mah lipoly and Jeti advance 4 esc but everything else is new. 30:1 micro sanyos, Turnigy 2204 brushless motor, HMC 3-9 single channel escs, and Spektrum AR-2 gram receiver.


Waterjetted the carbon fiber plates. Surprisingly I didnt have to use fodder plates to prevent the delamination. I just used a large lead-in, and low-pressure settings. There was some delam happening around the frame, but nothing superduper glue could fill in.


I had a moment of boredom while it was raining and decided to try engraving on Carbon Fiber. It won't cut but instead seems to melt the epoxy a bit. I guess an experience not to be repeated.


Wiring the beast is hell. I made a minor design change on the fly. Originally the robot was to use .5" standoffs to space the innards, but I opted for .375" because the motor would have required a massive hub to make up the height deficit. As a result, everything was 2x crammed in the fuselage. I had to buy the spektrum AR-whatever 2 gram receiver with the micro JST plugs to make it fit.


STILL I had to remove the micro JSTs and direct solder. [note to users: spektrum decided to be crafty and switched the positions of the 5v+ and gnd on this receiver. BE WARNED]

The HMC3-9's were angled (WTF) and flipped to fit. Only one superbus was used for power.

Somehow, it all fit.



After turning down the wheels from 1.5" to 1.125", I finished the bore on some old Vrogy blades Seth Carr of Team Lab Rat graciously donated/sold cheaply.


Bam. A robot. I added and bent some strips of grade-5 titanium to bring it up to weight and add protection. It looks very similar to Wazio's Pookie if anyone remembers that being built. Eitherway, it performs like a champ. Gryos like crazy, quicker than any version of P150, can rip through 1/32" steel like frozen butter.

Minor tune ups were made to the other robots as necessary. DDT required no additional servicing (as usual), Cake was lubricated and modified to include mechanical locks on the drum shaft instead of set screws (because setscrews suck), and P150 was rebuilt as noted above. I am concerned for the needle roller bearings in Cake because I was unable to remake the shaft so there is some audible play in the shaft. Could damage the rollers, so I'll bring the old drum as a back up.

PA Bot Blast on July. Cheers!

Also, Cheesecake.

Bot On! (The Victors)

Yesterday was the Gulf Coast Robot Sports competition at the Hobby marketplace down in Bradenton, Florida. And as you know, I took my three entries (Pacman, DDT, and P150) there. How did they do? Lets hit the break down.

DDT: 3 wins, 1 loss. The champ!
DDT was amazingly well behaved compared to previous outings. I kept the throttle about midway for most fights, and it kept the damage high, yet the recoil low. I might have to keep that tactic for later on. But I had only four fights because I had a first round bye and then an opponent who did not show up. So all in all, i fought against two other competitors: Piranha and Sporkinok.

V. Piranha: Piranha sported a mean vertical Ti blade directly powered by a 2212 sized brushless motor. I knew this would not be pretty, since Mike is a good driver and his bots are pretty tough. I knew wheel shots could kill me, so I decided to not allow him the chance. I lined up out blades every time and went for the "safe" impact since my blade was larger, thicker, and faster than his. He climbed DDT's front cover a few times, and flipped from some sparky hits, but soon his brushless motor had come apart and his blade bent, he decided to tap out giving me the win.

V. Sporkinok: The spork returns, but even more ridiculous than before! Now he is a 22.2v thwacker with a foot long boom of Al rod. He was fast, and almost uncontrollable, but as we fought, it didn't seem to matter... my blade was too low! It would go right under neath him, and the only thing i could hurt was the spork or the wheels. But he was so wide that it was tough, and i thought i might lose this to a judges decision. But after chasing him down, he ended up on my snout high centered, and I was able to put him out through the pit. But this was only the first of three encounters. After he beat Little Scoop in the Semi-finals, we met in the finals match 1. This time, he held a wedge attachment to try and keep me at bay. It worked in an odd way. It was enough hinderance to give a really good catch when we collided and we both flew around, with me hitting the pit. Finals match #2 started out poorly for Spork. A gyro and a change, and he was down one wheel. He tapped out giving DDT the victory.

P150: 2 wins, 1 loss. The champ!
In this I am not counting the forfeit by Nano Nightmare because I believe a fight could have occurred. No idea why he gave in though... But regardless, P150 was my second victor this competition. We ran double round robin fights in this because we only had three fairyweights.

v. Doodle Bug: I fought Doodle Bug, a Ti plated pusher, first. I spun up and he collided with me with sparks flying about. I was having control problems the whole time; the robot would go into FBS mode all too often, not like it usually does. So I suppose I got lucky, and one impact blew one of his tires out. He tapped giving DDT the win.

v. Micro Nightmare: Basically the miniature version of the miniature version of the large heavyweight, Nightmare. It sported a very similar weapon system to my own, but a slower drivetrain. I suppose I could have eaten his wheels easily, but with my control problems, he hit mine first, dropping the blade to the floor after he ripped it away. Sure I could still drive, but I was set in constant forward with the blade on the ground. At the same time, his weapon fell off, so all I had to do was stay alive! I got some light pokes at him, but an unlucky steer sent me into the pit. Time for the second string.

v Doodle Bug 2: Fighting with only one wheel was interesting. I replaced that sagging side with two nuts stacked on top of each other to give the proper blade clearance. So driving for me, was basically doing the crab walk, or using inertia to do a spin attack if he came close. There were some sparks, and some close calls when he managed to get behind me, but one lucky shot punted both robots away from the wall, where he went out of the arena, and I stayed in.

Nano Nightmare was unable to fight for the second bout so he awarded me the victory. It was a shame, I was actually looking forward to this bout.

The two victorious robots allowed me to pick up two prizes awarded at the event, totalling to $90 in gift certificates to the Robot Marketplace. Thanks to Jim, Seth, and the whole gang! I had a blast!

But now onto the big oaf...

Where'd ya go Jamo?

I've been busy. That is no secret. Many of you have no idea, because I seem just as (un)responsive as usual, but truth is, I have been quite busy.

Last post, I detailed some of the tasks I had to hit for the upcoming Gulf Coast Robot Sports competition at the Hobby Marketplace. Between then and now, I got all three robots completed! Woohoo! Okay, technically Pacman is charging, but who gives...

So to knock off the easy ones first, P150 and DDT are complete. Last post I outlined the new motor mounting scheme for DDT. The motors dried in, and I slapped some tape over the back. Looks brand new and ready for combat! P150 required a little more work, but nothing strenuous. I took apart my last spare GWS PicoBB servo, and replaced the topmost portion of the casing. Then I glued the motors in to complete the robots. Some quick test drives, and charges, they appear to be ready to kick some butt!












Pacman was not as easy. After a trek to Skycraft surplus store, I bought some replacement o-rings to use as drive belts. However they were too tight! How terrible! I tried to remelt some old belts but it turned out like junk. Apparently the material doesn't take too kind to fire, and instead of melting, just bursts into flames (sorry, no pictures).

I went to Home Depot to try and get the rings I needed: no dice, they were just too small. The largest they had was about 1.25" dia, when i needed 1.5" or something around that. I was about to leave, when my mom had the brilliant idea of using bathtub washers. Sure they start out very wide, but some quick work of the sheers, and suddenly they are custom made rings!










Some additional upgrades include a nicely polished output shaft, some added flats to help aid torque, upping the size of the weapon hub set screw, and maximizing the output pulley diameter for quicker spinup times. Check it out!

To Bot or not to Bot...

... that is the question.

Today is Tuesday and this Saturday is the Gulf Coast Robotic Sports competition hosted by the Hobby Marketplace. I am still trying to decide if I will compete or not. I love to fight robots, but somewhere between losing $30 (in entry fees) and my parents wanting to take me to my driver's test, it makes me second guess. Either way, I am still preparing the robots for Dragon Con in August.

First up, is my Antweight, DDT. At BARF, he did a good amount of damage, but after 5-6 competitions hte parts are wearing down. The motor mounting blocks actually fractured and broke completely on one side; into 5 pieces to be exact. I could not let this happen again.



Here are the UHMW motor mounts I created. Same overall dimensions, but the different material should make it more shock resistant. And yet, I didn't use them.




Here is what I actually did. I bought some standoffs to hold hte top armor, and then simply glued hte motors down like in some realier robots. It looks cheesy, but has actually been the best method in my opinion. No motors broken, and never has a motor come lose. It is just a pain to fix if a gear explodes.



Pacman got a weapon system change. When I got my wisdom teeth removed, I swung by the surplus store and bought some tighter O-rings so the weapon couldnt spin up faster. A lack of friction was costing Pacman some good seconds. But the O-rings were too tight. They transfered all the friction and the darn Wattage Cobalt actually sucked all of the current from the batteries. Ugg, I need another solution.

Easy solution. I changed the ratio of hte belts. The old setup was somewhere around 3:1. Decent, but for more torque, I made the blade pulley larger. Now it has something around a 7:1 ratio. This will mean lower top speed, but really, I never even GOT to top speed at BARF. Recent tests show that this configuration is a solid idea anyway.

Last, is P150. I have never introduced P150 here before, but simply it is hte smallest robot of the fleet. A 1/3 scale of DDT in a sense, definately one of hte most dangerous Fariweights in the nation.

It is in pieces... See the pretty pile of parts? Last GCRS, I foolishly put it in the Antweight rumble, where it made lots of pretty sparks, but it smashed both of its drive motors and its weapon motors. I already fixed one drive motor, but the bearing retainers on the weapon and the casing on the second drive motor are poo.




More updates to come later. And oh, the videos from the last event are uploaded on my Youtube. Cheers!