Meet The Bot:
Razors Edge was the very first bot designed and built by RE Combat Robotics President Owen Cokley, with work on the bot starting all the way back in 2017.
A hub-motor driven, 15 lb. drum spinner is far from the easiest design to start with--and the initial CAD of the bot shows the concepts that were toyed with, including 2 and 4 wheel drive, a feeder wedge on the drum, and a ludicrous number of batteries due to a calculation error.
The first version of the bot was built to compete at the Xtremebots 2018 Fall event in Dayton Ohio while Owen was at Centerville High School.
Key features of the robot included:
Hub-motor drum using an E-flite Power 60 outrunner.
Castle Phoenix Edge 75 Amp Weapon ESC
Banebots P60 and RS550 Brushed drivetrain
Robot Power Scorpion XXL drive controller
6S Lithium Ion batteries
1/2" 6061-T6 aluminum frame
Mild steel drum, with bolted mild steel teeth
UHMW front and rear skids
The First Event
Razors Edge V1 proved itself to be a competitive design, going 6-1 and taking 2nd place at its first event. Overall there were two main takeaways from the event:
The bolted teeth ripped out of the drum, causing the robot to shake itself to death
The hub motor eventually broke due to the undersized weapon bearing breaking
Additionally, both of these failures occurred during the final match when going weapon-to-weapon with a beater bar armed robot.
Owen didn't go home empty handed though, and was able to win the Xtremebots "Most Innovative" award for the work on Razors Edge's hub motor.
The Second One
Razors Edge V2 was a massive change from the first. While the overall concept and look of the bot stayed the same, there were a ton of internal changes:
3/4" 6061-T6 aluminum frame
Brushless drivetrain, with Propdrive 2826 1000kv motors and Mamba X ESCs
Grade 5 Ti drive axles
Overall smaller size
New gigantic drum bearings
New Mamba Monster X reversible weapon ESC
These changes were all aimed at solving the issues experienced at the previous event, and the brushless drivetrain was added to shrink the footprint of the robot.
Ultimately, the new changes worked--but the build was rushed. The hub motor ended up breaking round 1 because Owen ran out of time to battle harden the weapon motor. Razors Edge's record ended up being 2-2 at this event due to being relegated to a push bot for most of the competition.
Not all went poorly though--this event, Razors Edge won Centerville High School $500 for being the most innovative bot, once again due to Owen's work on the hub motor.
Disappointed with the performance at the last event, Owen signed the bot up for the 2019 NRL National event a couple of weeks later, and got to work making changes.
In order to fix the issues from the last event, the broken weapon motor was replaced with an Alien Power System 5065 500kv sensored outrunner and a new-stronger mounting system.
With this fix, the bot was near-indestructible at nationals, going 7-2 at the event. The two losses were from a massive hit on the rear of the bot which broke the power switch, and melted every set of batteries that were brought because no-one anticipated fighting 9+ matches with tight turnarounds.
Individual match footage from this event is available on the RE Combat Robotics YouTube Page.
Xtremebots 2019 fall was the first event where team RE Combat Robotics was officially formed, and Owen started running the bot independent of any school sponsorship. For the Event, Razors Edge received an all new frame, as well as a brand new wire EDM cut tool steel drum donated by Triangle Precision Industries.
Additionally, the bot moved to using a custom made power switch, Sidewinder 1/8th ESCs for drive control, a 750kv weapon motor for high speeds, and a large steel plate added to the rear or the bot for additional armor.
Fall 2019 was also the first event where Owen's younger brother, Cale, built his first bot on a team at Centerville High School, and brought Cyclone to the event.
This event, Razors Edge was finally able to stretch its legs and run through an entire event nearly damage free, and take home team RECR's very first 1st place trophy.
Cale and Centerville high school were the only ones able to put up some resistance against the bot's run, with the best fight of the night definitely going to Razors Edge vs Eddie.
This event was also the first time Owen filmed an event recap and uploaded it to the RE Combat Robotics YouTube Page, a trend which the team tries to keep up on and put out a recap video for every event we attend.
For all the matches and full event recap for this version of the bot, check out the recap here.
COVID In The Cage
The next event Razors Edge attended was some time later thanks to COVID, but during the off-season team RECR was busy making changes. Razors Edge was upgraded with:
To break these changes in, team RECR headed out of state to take 1st place at Rage in the Cage 2021. A full recap of this event can be watched here.
Spring of 2022 marked the return of Xtremebots, as well as Razors Edge. To prepare for this event, Razors Edge was upgraded with a couple of new components:
Smaller drive ESCs tried out on Kaleidoscope
A spare Kaleidoscope power switch
New carbon fiber supports for the hub motor
A new UHMW top cover to protect against top attacks
Because Owen was busy with running Kaleidoscope, Cory Cokley ended up driving the bot to yet another first place. During the event, team RECR didn't do much more than open the cover and change the batteries on the robot, and let it walk right through the field.
In the second to last match, Razors Edge's drum was cracked open against Caden Korzan's bot Earl, but miraculously continued to operate fine--giving the hub motor a final test of durability.
Razors Edge is currently living out its days as a wall hangar at the RE Combat Robotics shop. The most recent Xtremebots event burned through the last set of spares for the bot, to the point where everything would need to be made new. While the team has some ideas as for what to do next, nothing is set in stone. It would be nice to add even more wins to its very impressive track record though...