I am excited to announce that SendCutSend has extended an initial sponsorship offer to Btown Sting. Honeycomb has been intentionally designed so that all parts are off the shelf, 3D printable, or Laser Cut at SendCutSend. I've been having all of my G5 Titanium, 6061, and AR500 components manufactured by SendCutSend for over a year now, and I've always been super satisfied with the quality, accuracy, and quick turn around I get on my parts. Even before this, I always recommended SendCutSend to people whenever they asked how I fabricated my parts.
It's been a while since I've updated the blog. I've been a bit lazy on it because of the lack of events due to covid, so I've been taking it easy just waiting for more events to open up. Since this event in February 2020, I've only competed in one other event. I'm going to spend the next day going over design changes and other updates related to the bot.
Event Recap
Round 1 - Dark Destroyr
I actually didn't get any video of this fight as we didn't have time to set up the camera and begin recording before the match started. Dark Destroyr was a fully 3D printed bot by a rookie team, I believe this was their first event ever. Dark destroyer was made mostly of PLA and PVC tubes. Once the match started I gave them one good hit and the PLA components shattered prompting a tap out from their team. 1-0 for the day.
Round 2 - H5N1
I've fought H5N1 previously, and I was super excited to get to fight them again. At the previous event at the same location they ended up winning the entire tournament, so I was super excited to get to fight a well designed destructive bot. Off the bat I noticed that my actuated ground scraping forks were working very well allowing me to get underneath their wedge and get the best of most exchanges. However, this is where I noticed that on every hit, my bot would pivot forward and the weapon would catch the ground sending my bot backwards as well (which cant be good for my belts or weapon motor). After a few good exchanges I eventually dislodged their top panel exposing their battery for the win. 2-0 for the day.
Round 3 - Snowfire
Sorry for the crap picture, I didn't have a better one, so I ripped it from the video.
After my morning look around the pits and watching their fights from earlier in the day, I figured that Snowfire would probably be my toughest opponent. Snowfire is a 2WD robot using the Fingertech Beater Bar as their primary weapon. Snowfire has a very rugged build with the only majorly vulnerable components being the foam wheels and weapon belts. During this fight once again I was noticing that during most exchanges even if I got the better hit in, my robot's weapon would catch the ground sending me backwards not allowing me to capitalize on any good hits I gave out. During this match I managed to launch Snowfire with their weapon at full speed into the acrylic side wall, punching out one of the panes. After much back and forth I eventually lost one side of my drive and was pitted by Snowfire. 2-1 for the day.
Round 4 - H5N1 pt. 2
We ended up meeting H5N1 a second time in the losers bracket. During this match it went similarly to the first one, with my forks really getting underneath their wedge giving me the upper hand in almost every exchange. We end up getting entangled a couple times, with the second time us staying entangled for the majority of the match before a stoppage was called. After the second entanglement they were stuck on their side with no way to self right. 3-1 for the day.
Round 5 - Snowfire pt. 2
Now that we've fought our way through the Losers Bracket, we are once again fight Snowfire in the finals match. Unfortunately for us, Snowfire quickly gets the better of the first exchange and removes one of our wheels, prompting a tap out from me. 3-2 for the day taking 2nd place with our only loses being to Snowfire.
Post Tournament Design Criticism
Identifiable Issues
On most exchanges due to the design of my side plates my robot tips forward causing the weapon to catch on the ground sending me backwards. This prevents me from being able to capitalize on my opponent while they're in a vulnerable position, and this also can't be very good for my weapon belts and motors.
Just as they have been historically my wheels are very brittle and tend to get broken way too often. They need to be a more durable material.
My weapon speed seems to be really low, I'm pretty sure that with the 1500kv motor and battery at full charge its only going about 150mph tip speed which is fairly low especially for beetleweight bots and I'm ending matches with over 50% or more of my usable battery left. I think if I got my weapon spinning faster I could really start delivering those super destructive knockout hits and really send robots flying to the roof.
Proposed Solutions
1.
Old Side Plate
New Side Plate
The idea behind this new design is that the weapon will now be supported directly under the shaft instead of 1 inch behind. With the old side plate I was essentially creating a fulcrum for the bot to pivot on with the weapon on one side and the rest of the body on the other. After an exchange the bot would pivot forward causing the weapon to catch on the ground sending me backwards. With the new plate, I have essentially removed the fulcrum now that the weapon is supported directly underneath. This should eliminate the bot from tilting forward and better improve my weight distribution which should also give me more traction on my wheels.
2.
I got polycarb wheel water jet cut. I really like the sandwich design with the rubber slips, so I'm going to continue to use that, but just replace the brittle acrylic with the new polycarb rounds.
3.
I'm upgrading to a 2700kv Propdrive V2 motor. This should push my weapon speed to around that 250mph sweet spot and really start to damage and remove parts from other bots.
We ended up finishing 2nd at Maker X Ohio. Big congrats to Snowfire for taking the tournament undefeated. I'm gonna throw together a quick video of our fights, we were unable to get our first and last fight due to extenuating circumstances, but we have our 2 fights against H5N1 and 1 fight against Snowfire. I'll probably do a full event recap at some point soon whenever I finish with the video, but with Midterms this week I'm quite busy.
As far as pros and cons go I'll make a quick list, a lot of these points are relative to the old design.
Pros:
Much higher damage, with my weapon assembly being about 70% heavier than the previous we were dishing out much more devastating hits consistently.
Ground scraping forks were pivotal to us winning most of our fights as they allowed us to get under other people's wedges and really toss them around.
ABS and the aluminum standoffs proved to be a lot more robust than the old design and allowed me to give and receive many more hits than I used to be able to take.
The grade-8 steel dead shaft significantly increased the durability of the bot by moving the load from the 3D printed parts to into the weapon assembly.
Making the 3D printed parts simply dividers rather than load bearing/structural components improved reliability, and even when a part would crack/chip it usually wont warrant a full replacement.
Looks cool AF.
Cons:
With the new weight of the weapon, on lower friction surfaces driving becomes difficult/impossible due to the weight distribution being quite front heavy.
Had a scare and got weighed at 3.2lbs, even though I've calculated the weight at exactly 2lbs15.7oz. I've also used multiple scales of a higher accuracy to weigh the bot prior to the event consistantly weighing in at 2lbs15.7oz +-.1oz. I'm going to chalk that up to inaccurate scale used by the event, because it kept fluctuating between 2.9, 3.0, and 3.2lbs. This scale also didn't have accuracy greater than one decimal place, and no oz or fraction of ounce weight accuracy. We ended up checking weight on other scales and concluded that the scale wasn't accurate.
Improvements:
Move the the fulcrum point where the skids touch the ground up .75" to put more weight on the wheels and improve traction.
Lower mid plate print density to allow for the fulcrum improvement.
Up the KV rating of motor from 1100 to 1500, which should increase the max speed of the weapon significantly.
A bit late, but I'm updating a couple posts leading up to MakerX Columbus Combat 2020 next weekend. First of all I'd like to recap Taproom Tapout and what it means for me.
Taproom Tap Out was a fairly successful tournament with 2 strong wins, 1 good loss, and 1 fight of me getting my shit tossed by a Weta. Since I already posted the video I don't feel like there is much more I can add that would be worth while.
The biggest thing after this tournament is that I no longer have any spare metal parts for Honeycomb. I've been working hard to get my new bot up and running.
The bottom image is not a fully accurate representation of the new design, didn't have a most recent render on hand.
List of changes: Old -> New
3D printed weapon motor mount -> aluminum weapon motor mount now attached to the frame with aluminum standoffs
3" total height -> 2-3/8" total height
2-1/4" chassis height -> 1-1/4" chassis height
live 3/8" aluminum weapon shaft -> dead 5/16" grade 8 steel weapon shaft (also changed to roller bearings instead of ball bearings)
side plates 1/4" aluminum -> 1/8" titanium
3" acrylic wheels -> 2-3/8" banebots wheels
sprocket and chain -> belts and pulley
polycarbonate wedge -> ar500 forks
4140 weapon teeth -> ar500 weapon teeth
drum design -> new hex drum design which should be robust and significantly heavier
no z-support standoffs -> z-support standoffs to help make the robot more robust between the top and bottom plates
flat back plate -> rounded back-plate so I can no longer get stuck on my back.
no side armor -> side armor to protect the shaft mounting point
Hopefully all of these changes will solve reliability issues, up damage, and potentially lead to more consistent performance across tournaments and throughout the day at tournaments. The bot was also redesigned to be 100% laser cut with the only part needing to be machined being the aluminum drum that the teeth mount on. I am also planning on completely removing the lexan wedge option and plan on potentially introducing a large fork/full wedge option to deal with some of the bigger spinners that have historically given me trouble in competitions. This would involve removing the weapon and all related sub assemblies and replacing all that weight with said wedge/forks. This modular option will not be ready for the next tournament, but this new design was created with this potential option in mind.
For this tournament we were headed down to Nashville, Tennessee's Adventure Science Center. We ended up getting there around 10:00AM Saturday morning of the event. We unloaded the car, and moved inside to the room that the tournament was going to be hosted in. We got set up at our table and got the bot ready for weigh in.
Ready for a tournament!!!
The box was pretty cool, with a pit on one side and a free spinning disk in the middle. So when attempting to accelerate tangent to the disk, the disk will just spin out and cause you to not move where you are expecting to, or when driving over the disk it may create variable driving conditions that few drivers are used to.
The box we will be fighting in.
I compiled all the fights and the rumble together into one video. Below the video I have some comments and thoughts I had about each fight. Due to the size of the bracket there were a max of 4 fights for the day. Sorry for video quality of the rumble, we didn't have video stabilization on :(
Fight 1 Honeycomb vs Tweetle - Quarter Finals
Tweetle is an overhead saw bot with a wide base and aluminum scrapes on the front. However, I noticed early on that the center 2 forks actually ride up a bit above the ground, and I suspected if I just went head on with my wedge, I would most likely be able to get underneath him and knock him around and really control the fight. All goes pretty well and I end up winning this fight with no issues. Only thing to do is recharge the battery.
Fight 2 Honeycomb vs Pyramid of Death - Semi Finals
Pyramid of Death is exactly what it sounds like, a pyramid shaped robot that is very low to the ground on all sides, and on one side it actually has a ground scraping metal wedge. I figured that my wedge could get under it on the sides without the metal wedge, as they were not actually touching the ground. Additionally, the drive train for Pyramid of Death seems relatively powerful, but slow and lacking wheel traction, so I think if I can get to one of the sides I should be able to push POD around and really control the fight. It ends up going well, I end up getting tearing up his wedge a bit and close out the fight with a nasty hit which completely flips POD over and he gets counted out.
Fight 3 Honeycomb vs Tweetle Round 2 - Finals
Tweetle ends up making it all the way through the losers bracket and we end up meeting again in finals. Over all my plan going into this match was about the same. Part way through the match however, I break my mid plate which holds my two bearing plates the proper distance from each other so my weapon shaft doesn't fall out. The two bearing plates separate from each other enough for the weapon shaft to fall out. This renders my weapon useless for the rest of the match, and I lose this match to judges decision.
Fight 4 Honeycomb vs Tweetle Round 3 - Finals
Since I was undefeated for the day, Tweetle had to win 2 times since we were in a double elimination bracket. After the break in the lasts match I pressed the two halves together and wrapped duct tape around it so that it wouldn't come apart again. I think as long as I continue to use the 3D printed center part, I may continue to just tape it as these 3D printed parts are good with compressive forces, but are pretty weak under high tensile forces, shear, and shock. So maybe the tape will be good insurance that the two sides wont come apart in the future even if the mid-plate breaks like it did during fight 3. With the weapon fully working, I was able to get a lot of good hits off during this last match. Tweetle ends up driving into the pit after a while. This is the final round and I ended up winning the tournament 3-1.
3lbs Rumble
The remaining functional bots took it to the arena to bout it out for 5 minutes. During this shoot we forgot to turn on our image stabilization so during some refocusing of the camera it ended up being pretty shaky for the majority of the match. :(
The Recap
Just like last time I think I still have some of the same issues with just material properties. Currently, I am designing a new 3lbs robot, and when I go to have parts cut for the new bot, I might have some new parts cut for Honeycomb to make it more reliable.
I think I could also cut down the size of my battery to 850mah, 650mah, or possibly even lower. Currently, I'm running a 1000mah 3S battery which is definitely over-spec'd for this bot. I could probably up the power of this bot by cutting down to a 850mah or a 650mah, but up to 4 cell battery for higher weapon speeds. Need to do some rough calculations, but current estimate is I can definitely reduce to a 850mah battery, possibly the 650mah.
Overall, this was a really fun tournament that wasn't too far away, hope to make my way back for the next tournament hosted by MTRAS. (Also love coming down for the BBQ :P)
This is pretty late, but I have been very buy with the start of the school year. Without wasting anymore time lets get into it. For this tournament me and RJ traveled to Wilkes-Barre, Pennsylvania. We left home about 10PM Friday evening, with plans on arriving there at about 8-9AM Saturday morning. Travel goes well without a hitch, and we end up arriving at around 8:30AM.
This tournament was hosted by Raymour and Flanigan furniture store, and they had the box set up in the middle of the Store, and it was the first thing you saw when walking in to the store. Very cool setup with a lot of couches and chairs surrounding the box for people to sit and watch the event.
The box setup in the main lobby of the store
When getting there, they had us move around back to their warehouse area which is where they had us set up pits.
I ended up wearing my old high school robotics shirt, represent.
Me rebuilding the weapon assembly for the 4th time that morning.
The first fight of the day was against Captain Doom. Captain doom had 5 ground scraping forks on the front of their bot and a powerful drive train that made them very difficult to bully around the box. Without my primary weapon this match was going to be near impossible to win due to their more powerful drive train and low ground clearance. At the end of the match however, we have a giant collision that ends up knocking something lose in Captain Doom and they are rendered immobile. We win the match and qualify for the round of 8.
Since Captain Doom was just a push bot, we didn't have any repairs to do outside of charging the batteries. This left us a lot of time to try and figure out why our weapon wasn't spinning up. Upon the recommendation of another builder (I can't recall who) we lowered the kv of our brushless motor and swapped from a 3200kv motor to a 1100kv motor.
Me rebuilding the weapon assembly yet again.
Finally ready, with the weapon working.
For the next match of the day, we were facing Mondo Bizarro. Mondo has a very nasty vertical spinner on the front, but a relatively weak drive train. So for this match I wanted to stay away from the front of his bot and get around to the sides and the back. However, this did not go quire as planned, and I took a lot of early hits that ultimately led to the failure of my weapon. This fight won me "Most Destroyed".
After it was all said and done, we were unable to continue on the day. We finished top 8 and got this cool gif.
cool gif
Overall Thoughts:
I think performance was pretty okay, but had issues with reliability off the bat. Below are a few thought on how to change the design and how to prepare for future competitions next calendar year.
Remove all 3D printed parts from the design. They are pretty rigid, but tend to snap and break instead of losing chunks and chipping. Want to switch over to UHMW for the mid and back plate, or possibly 2 different materials. The logic being that the back is subjected to more hits, and the mid is subjected to more torque and sheer force as the different sides get hit. Will probably get completed after the November Tournament in Virginia.
Make the permanent switch over to a lower kv motor. Maybe not 1100kv as that seems a little bit too low, but under 2000kv. However, all I have on hand are 1100kv, I'll see if I can find some 14-18 hundred kv motors before the next tournament. (Will probably get completed before the next competition in 2 weeks)
Practice driving, I really shot myself in the foot not practicing driving more, with that being very apparent in the Mondo match.
