| Weapon Drive || 2x Badass 3515 710kv. Mamba X ESCs. Gear ratio 1:4
|-
|-
| Drive || Repeat Ultras
| Drive || Repeat Ultras
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|}
|}
=== <u>V3</u> ===
=== <u>Design Iterations</u> ===
==== <u>V5</u> ====
Inertial-v5 will compete at Hive Hysteria in July 2026
The name of the game with v5 is rigid mounting of the parts that matter, namely the two parts that kept failing during v3/4 competitions
[[File:Inertial-v5-mounting-points.jpg|thumb|The five points of contact for the shell top plate in Inertial-v5]]
Those are
# The shell itself
# The shufflers
Both were subject to a number of issues that arose from poor mounting
# The shell would rock when spinning up (see Caldera and Grim Ripper fights)
# The shufflers would get misaligned and melt themselves (see v3 fights)
So both are getting serious mounting upgrades
# The shell is going to be mounted along 5 points, rather than just the center axle
# The shufflers are going to be on aluminum mounts, rather than just TPU.
There are also some other upgrades that are included as part of v5
# The shell is going to be driven by friction (polyurethane wheels) rather than by gears, this solves the v3 gears-melting-upon-spinup problem, as well as the v4 motors-melting-themselves-upon-impact problem. This required a serious overhaul of the design of v5, accomodating a more rigid mounting (again, that's the through theme for v5) to accomodate a spring-loaded mounting mechanism for the wheels (see Drift's design). This requires a number of other things to also become quite rigid/adjustable, namely the top plate (which is now aluminum) and the horn mounting (which is now aluminum and adjustable (though maybe after prototype 1 it'll be spring loaded as well))
# The shufflers are integrating an idea from The Wall's shufflers, namely wrapping the cams in bearings. This solves a huge issue that has been plauging the bot since v3, namely that the shufflers would get gummed up and eventually grind to a halt. Hopefully including bearings on the cams will solve this issue entirely.
I'm excited for v5, though it is early stages now (06/2026), let's see how it performs at the Hive in July
===== An aside about building a shuffling shell spinner =====
When designing 4wd vert number #1000, there's a lot of design inspiration you can get. It's not a solved problem by any means, but there are plenty of successful bots to steal ideas from and integrate into your own bot. Whether that's from your own weight class or higher.
There are kits, bot breakdowns from top builders, and speciality products made by JCR or Repeat.
But building a shuffling shell spinner is a totally different story.
There's literally nothing for me to steal ideas from. No other bots in the weight class, and only one other bot (Chonkiv) really that I can take inspiration from. And trust me I've stared at Chonkiv whenever I had the chance, but ultimately so many things are different that I'm basically working from scratch.
All I get are little bits and pieces, a shuffling mechanism here (12lb shufflers like Weather Report and Galaxi), a weapon drive there (Chonkiv and Drift), but there's literally no one in the weight class that I can "copy".
''I don't think this is a bad thing though.''
Inertial is such fun to work on because it's jam packed with ideas that are truly my own. The spring mounting mechanisms, the outer bearing mounts, even the cams and the shuffler design are all unique to Inertial because I came up with them on my own.
If you ever see me in the pits and are curious about these unique design elements just come by and I'll happily rant about them.
This is just a random aside but I really do encourage anyone reading this to take up a unique design for a robot. Make something truly unique and experiment with it. Learn from your mistakes and build something that ''you can really call your own''.
Maybe you'll have to be the worst ranked robot in your weight class for awhile, but that won't last forever. Or maybe you can just be like me and not care at all about results.
Working on Inertial is one of the most fufilling and mentally stimulating things I've ever done and I'm so glad I dived straight into the deep end (12lb AND a shell spinner) for my first ever robot (of any kind).
Anyway soapbox rant over.
==== <u>V4</u> ====
[[File:Inertial-v4.jpg|thumb|Work in progress Inertial-v4]]
Inertial-v4 will compete at NHRL Feburary 2026
<u>What went wrong with v3?</u>
If you watch the fights with Inertial-v3 you'll see that they're both quite disappointing, the bot would just seemingly stop moving and stop spinning.
This was due to two issues
# The clearance between the shell and the shufflers was basically zero, which meant any instability (from hits for example) would lead to the shell clipping the shufflers, leading to the shufflers melting and jamming up
# The weapon motors drove the center gear via plastic 3D printed gears. These would consistently melt and cause the weapon to fail
So v4 aims to address these two main issues in a minor design pass. Most of the DNA of v3 is good (I think?) so I want to give it a proper shot to perform by fixing these two glaring issues. This is more of a v3.5 than a v4.
<u>Changes</u>
* Center gears replaced with metal 3D printed aluminum. Pinions replaced with press-fit 3D printed aluminum
* The entire shell is bumped upwards by a good amount, increasing the clearance to an acceptable amount
* A simple housing was printed to keep the shufflers in place
So overall, a very minor design pass, v5 will be a much more major design overhaul to address the new and exciting issues that v4 will hopefully uncover.
==== <u>V3</u> ====
[[File:Inertial-v3-wip.jpg|thumb|Work in progress Inertial-v3]]
[[File:Inertial-v3-wip.jpg|thumb|Work in progress Inertial-v3]]
Inertial-v3 will compete at NHRL November 2025
Inertial-v3 competed at NHRL November 2025
<u>Notable changes</u>
<u>Notable changes</u>
Line 38:
Line 113:
Some things were very bad
Some things were very bad
[[File:Inertial-v2-blade-failure.jpg|thumb|The failure mode of the V2 blade. Completely snapped by The Invisible Hand right where the blade thins to accomodate the shell bolts]]
* The battery being only velcro-d on (cringe) meant the bot would lose its batteries often. See the Galaxi fight and the Chonkiv rumble.
* The battery being only velcro-d on (cringe) meant the bot would lose its batteries often. See the Galaxi fight and the Chonkiv rumble.
** The complete lack of a top plate was my downfall multiple times
** The complete lack of a top plate was my downfall multiple times
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[[File:Inertial-v2.jpg|thumb|Inertial-v2 at June 2025 NHRL]]
[[File:Inertial-v2.jpg|thumb|Inertial-v2 at June 2025 NHRL]]
=== <u>V2</u> ===
==== <u>V2</u> ====
Inertial-v2 competed at June 2025 NHRL, where it went 1-2
Inertial-v2 competed at June 2025 NHRL, where it went 1-2
Line 77:
Line 152:
* Re-soldered electronics
* Re-soldered electronics
=== <u>V1</u> ===
==== <u>V1</u> ====
Inertial competed in its inagural event in May 2025 at NHRL, where it fought in a single fight and forfieted its second fight, going 0-2
Inertial competed in its inagural event in May 2025 at NHRL, where it fought in a single fight and forfieted its second fight, going 0-2
2x Badass 3515 710kv. Mamba X ESCs. Gear ratio 1:4
Drive
Repeat Ultras
Power
2x 1600mAh 6s LiHv
Design Iterations
V5
Inertial-v5 will compete at Hive Hysteria in July 2026
The name of the game with v5 is rigid mounting of the parts that matter, namely the two parts that kept failing during v3/4 competitions
The five points of contact for the shell top plate in Inertial-v5
Those are
The shell itself
The shufflers
Both were subject to a number of issues that arose from poor mounting
The shell would rock when spinning up (see Caldera and Grim Ripper fights)
The shufflers would get misaligned and melt themselves (see v3 fights)
So both are getting serious mounting upgrades
The shell is going to be mounted along 5 points, rather than just the center axle
The shufflers are going to be on aluminum mounts, rather than just TPU.
There are also some other upgrades that are included as part of v5
The shell is going to be driven by friction (polyurethane wheels) rather than by gears, this solves the v3 gears-melting-upon-spinup problem, as well as the v4 motors-melting-themselves-upon-impact problem. This required a serious overhaul of the design of v5, accomodating a more rigid mounting (again, that's the through theme for v5) to accomodate a spring-loaded mounting mechanism for the wheels (see Drift's design). This requires a number of other things to also become quite rigid/adjustable, namely the top plate (which is now aluminum) and the horn mounting (which is now aluminum and adjustable (though maybe after prototype 1 it'll be spring loaded as well))
The shufflers are integrating an idea from The Wall's shufflers, namely wrapping the cams in bearings. This solves a huge issue that has been plauging the bot since v3, namely that the shufflers would get gummed up and eventually grind to a halt. Hopefully including bearings on the cams will solve this issue entirely.
I'm excited for v5, though it is early stages now (06/2026), let's see how it performs at the Hive in July
An aside about building a shuffling shell spinner
When designing 4wd vert number #1000, there's a lot of design inspiration you can get. It's not a solved problem by any means, but there are plenty of successful bots to steal ideas from and integrate into your own bot. Whether that's from your own weight class or higher.
There are kits, bot breakdowns from top builders, and speciality products made by JCR or Repeat.
But building a shuffling shell spinner is a totally different story.
There's literally nothing for me to steal ideas from. No other bots in the weight class, and only one other bot (Chonkiv) really that I can take inspiration from. And trust me I've stared at Chonkiv whenever I had the chance, but ultimately so many things are different that I'm basically working from scratch.
All I get are little bits and pieces, a shuffling mechanism here (12lb shufflers like Weather Report and Galaxi), a weapon drive there (Chonkiv and Drift), but there's literally no one in the weight class that I can "copy".
I don't think this is a bad thing though.
Inertial is such fun to work on because it's jam packed with ideas that are truly my own. The spring mounting mechanisms, the outer bearing mounts, even the cams and the shuffler design are all unique to Inertial because I came up with them on my own.
If you ever see me in the pits and are curious about these unique design elements just come by and I'll happily rant about them.
This is just a random aside but I really do encourage anyone reading this to take up a unique design for a robot. Make something truly unique and experiment with it. Learn from your mistakes and build something that you can really call your own.
Maybe you'll have to be the worst ranked robot in your weight class for awhile, but that won't last forever. Or maybe you can just be like me and not care at all about results.
Working on Inertial is one of the most fufilling and mentally stimulating things I've ever done and I'm so glad I dived straight into the deep end (12lb AND a shell spinner) for my first ever robot (of any kind).
Anyway soapbox rant over.
V4
Work in progress Inertial-v4
Inertial-v4 will compete at NHRL Feburary 2026
What went wrong with v3?
If you watch the fights with Inertial-v3 you'll see that they're both quite disappointing, the bot would just seemingly stop moving and stop spinning.
This was due to two issues
The clearance between the shell and the shufflers was basically zero, which meant any instability (from hits for example) would lead to the shell clipping the shufflers, leading to the shufflers melting and jamming up
The weapon motors drove the center gear via plastic 3D printed gears. These would consistently melt and cause the weapon to fail
So v4 aims to address these two main issues in a minor design pass. Most of the DNA of v3 is good (I think?) so I want to give it a proper shot to perform by fixing these two glaring issues. This is more of a v3.5 than a v4.
Changes
Center gears replaced with metal 3D printed aluminum. Pinions replaced with press-fit 3D printed aluminum
The entire shell is bumped upwards by a good amount, increasing the clearance to an acceptable amount
A simple housing was printed to keep the shufflers in place
So overall, a very minor design pass, v5 will be a much more major design overhaul to address the new and exciting issues that v4 will hopefully uncover.
V3
Work in progress Inertial-v3
Inertial-v3 competed at NHRL November 2025
Notable changes
Everything. The entire bot was redesigned from the bottom up. The only components that survived the transition were the kakes, shoulder bolts, 20mm aluminum rod, and Repeat Ultras
Design philosophy
Some things worked well on v2
The geared dual motor spin-up was excellent despite the high MOI of the shell and blade
The TPU shell was excellent and survived a Chonkiv hit during the freestyle
The TPU core was also excellent and survived getting roofed by Galaxi. The SPLA core in contrast exploded when it was shot up by The Invisible Hand
The long counterbalanced tooth gave excellent reach
The Repeat Ultras performed very well
Some things were very bad
The failure mode of the V2 blade. Completely snapped by The Invisible Hand right where the blade thins to accomodate the shell bolts
The battery being only velcro-d on (cringe) meant the bot would lose its batteries often. See the Galaxi fight and the Chonkiv rumble.
The complete lack of a top plate was my downfall multiple times
The blade was too thin and prone to failing catastrophically. See the fight against The Invisible Hand.
The shell was high infil instead of having a heavier blade. This is both a waste of material and of weight.
There were also some things left on the table
Mobility is uniquely an almost non-concern for shell spinners, making shufflers a very easy potential power buff
While everyone in the 12s loves the BA 2820, the shell is nearing the weight and MOI of a 30lb weapon, meaning we should look for 30lb weapon drive
The internal gear ratio was also not ideal, leading to an impossible to reach max tip speed
Everything relies on a single battery and a single switch, leading to those two both being single points of failure
So this design revision was based around addressing those problems, while attempting to keep all of the strengths of V2
A geared 1:4 weapon drive with dual BA 3515 with Mamba X ESCs
The two halves have split batteries and switches, leading to the receiver being the only single point of failure (v4 will address this)
A top plate. V2 did not in fact have a top plate. This top plate is not defensive (it's a thin layer of tpu), it's meant to keep the insides in, which V2 was prone to ejecting
A 1/2" AR500, 23" dia weapon blade
A low infil shell with top stiffeners to fix the bending issues encountered during testing
Inertial-v2 at June 2025 NHRL
V2
Inertial-v2 competed at June 2025 NHRL, where it went 1-2
Due to the short turnaround between May and June, most of the DNA of the bot stayed the same from v1, with a few important changes
Notable changes
Geared weapon drive instead of belted weapon drive
A full TPU outer shell
Metal 3d printed wheels that combined the pulley hubs and the cleats
A slightly more sane weapon tooth profile
Re-soldered electronics
V1
Inertial competed in its inagural event in May 2025 at NHRL, where it fought in a single fight and forfieted its second fight, going 0-2
Inertial-v1 had a number of interesting quirks
The asymmetric drive motors on Inertial-v1
Asymmetric drive: In order to fit everything in the shell, an asymmetric belted drive was chosen for Inertial-v1. This actually worked well despite of how jank it looks.
A side profile of Inertial-v1, showing off the dual belted weapon systemA S3M dual belted weapon drive. This belt profile does NOT work for a high-moi 12lb weapon
The shell was half TPU and half NylonGF. This was a mistake, as you can see by Marshmallow ripping the nylon pieces to shreds during its first match
Along with a number of straight up design mistakes
The poorly designed blade and 90 degree rake angle
The wheels and pulleys were attached with m1 screws. I could not find a hex key small enough to even turn them so "screwed" them in with pliers. This did not work, as evidenced by the wheels falling off BEFORE THE MATCH EVEN STARTED
90 degree rake angle. Need I say more?
The bot lost because of
The wheels falling off
The belts failing
The shell being half nylonGF
The electronics being poorly soldered and failling after the first match
