@Kraken4me Thank you very much, that poster is up there with one of the best things i’ve made, loved putting it together.
@morgan_ls Thank you. I will go into detail regarding that srimech when I get to writing about v4, people seemed to love it. And the horizontal frog, maybe if someone twists my arm enough 
But without further ado, It’s time for:
Sir Lance-a-frog v3
aka “One of the UK’s many beetlweight 4-bars”.
4-bars are cool.
In the early 2000s, on the rare occasion I was able to catch a showing of Battlebots on Comedy Central here in the UK, there was one bot that always stood out to me – Biohazard. It always stood out as such a cool robot design, super low with the side-skirts, and the lifting arm that would just effortlessly tip and hoist other robots over. And after my first year in robots and using the flappy style lifter design, I felt like a 4-bar would be more effective overall, and to take things up a notch. It was something I initially wanted to try and adapt Frog v2 to have, yet after hmm-ing and haa-ing for a while, eventually settled on making a new version, that could incorporate a few other tweaks:
[Experimenting with bits on v2, post UWE 2019. Maybe it could have worked ok, but to give the idea a proper go, it was time for a new chassis.]
-
A redesign of the back of the bot to reduce the mount of panels and parts to manufacture, give more area for the back panel to bolt into. Why? V1 and V2 had two angled back panels, which had to screw or bolt into the chassis rails or the base/top plates themselves, and they never felt 100% secure, and there was not enough space to use the same fixing method on both. Simplifying this would allow me to use one method that was more permanent.
-
Incorporating a link door into the top plate of the robot. Why? The link door was located on one of the back panels, so was now moved to the top plate to retain easy access to the link. And there was no way I was going back to a bum link.
-
Having a spare top plate that could be set up to have a weapon setup similar to v1 and v2. Why? A contingency plan, should the 4-bar be irreparably FUBAR’d at an event, I’d be able to pivot and still run an active lifter, rather than be stuck with no active weapon.
[Chassis bits. Cut out with a multitool. No death by a thousand drill holes this time!]
[Once cut, sand everything down to the dimensions needed with one hand, because the other is needed to pull the trigger on the drill. Make all the dust. I was wearing masks
before it was cool!]
[
CHASSIS
ONLY
]
The 4-bar itself was designed with the aid of some knock-off Meccano, as designing something like this from scratch was something I needed to do visually. I’m not smort enuf to just go into CAD and smash this out in a few minutes, it had to be something I understood and could look at in real life. With the Meccano, it helped me get a good idea of how long he arms would need to be in order to get the motion I wanted, AND to fit into the constraints of Frog’s internal height. When I had gotten my head around that, then I was comfortable attempting to design the actual linkage in SketchUp – not an ideal program for testing linkages due to the lack of proper joint support, another reason for wanting something to work on IRL.
[I’m glad this made sense to me back then, because looking at this in December 2024 (and taking the photo of it now) it’s a bit “huh?”]
It was also decided at this point to bolt the arms to the chassis walls, rather than having it’s own rail in the middle of the bot to bolt to. This was done to again keep the part count and the weight down. Figured the space was there and the mechanism would fit there, so that’s how I proceeded. Trying to keep the weight down nearly buggered things up however, when I decided to lighten the chassis rails with two large holes, and nearly had to scrap and start over due to picking the worst place to put these new “speed holes”. Surely these will not cause problems later.
[Video of the first test of the 4-bar. Cuppa in progress (not pictured but heard)]
[v3, functional, with the new bent wedge design. 5mm HDPE bent with a jet lighter. Job done.
I do not remember WTF I did to the lance between cutting it and here. Why is there a hole there, past Nick??]
V3 proved to be quite adaptable during it competitive lifespan, or rather, I was less wary or hesitant of adapting it. At SXS it had a version of the 4-bar that re-used the titanium plate from v2, and it briefly fought as a front-hinged flipper at BBB Champs ‘22, because why not? It could also self-right in this form, imagine being able to self-right during a fight, crazy…
[He do a front flip]
Overall, these were only relatively small tweaks compared to v2, and in theory allowed me to reuse certain parts and pieces from v2, on v3. However, this was only done on certain situations and occasions.
Internally, v3 was very much the same as v1 and v2 before it at first. There were gradual changes, namely the move to brushed 22mm motors as 25s became a little harder to source and keep reliable. Towards the end of it’s run, I also moved to the BBB Dual ESC, which helped in simplifying the internal spaget.
Frog v3 is also where I started to get ✮ 
𝒻𝒶𝓃𝒸𝓎 ✮ with the liveries and paint jobs. Whilst v2 had started the paint trend, and I’d enjoyed the gunmetal/copper look, It became a great source of satisfaction and distraction to decide what new look I would give Frog for an event. And a lot of these ideas were spur of the moment ones that ended up being fun. “What if I made decals for this version?”/”Oh hey, this event is super close to Halloween.”/”Froggy Chair my beloved.”
Doing robots in general has given me such an outlet to be creative and to get ideas out and into the world, and it is a great feeling to have an idea come to fruition, expressed in the way you wanted it to be. I’m very proud of what I’ve done and always wanted to be one of those builders that is making something cool-looking, even if it’s never ultimately super-competitive.
[So many looks, which one is your favourite?]
For a robot built in 2019, it was always fun to try and keep it running, push it to do as many fights and events as possible. Making it all the way into 2023 feels impressive to me (even though I didn’t compete for two years thanks to da Virus), and for a while it lived up to the reputation of being a tanky mofo… there was plenty to be proud of with this robot. The Last Chance Rumble in Bugglebots S2, the run to Top 8 in it’s return at Robot Rebellion in 2022 showed what it was capable of on a good day.
I will say though, in my opinion the tankiness definitely dropped off in the last few events it ran. The deep runs felt less possible towards the end, for many reasons. There are and were a ton of new and exciting robots that’ve appeared that have done some super stuff (Rudimental, Luchador, EMP and Chucky do the lifty/flippy thing far better than Frog ever did), existing robots improved a ton, drivers matured and got/continue to get the best out of their robots (Abracagrabra, Babrog, Attitude Adjuster spring to mind), and spinners in general became so potent even compared to where they were a few years prior (Gizmo, Propane, Icebreaker to just name a few) - and Frog v3 never really made a step forward to keep up with that. There was never a real ‘magic bullet’ that was going to get Frog to go from ‘Top 16’ to ‘Easy Top 3’.
[So bemdy]
And then it got smoked. Remember the speed holes from earlier? In it’s final competition fight at Robot Rebellion 2023, the right-side of the chassis was was basically torn in two by Baby Dead Bod, a horizontal spinner that likes to throw hands and wheels/motors at its opponents and itself from time to time. Over the course of one relatively short fight, it tore that large, major section of the chassis off at its weakest points, leaving a mounting point for the 4-bar hanging on by the smallest amount of warped HDPE. Turns out if you give a horizontal with dutty strength a nice opening to hook into, it can absolutely ruin your shit, fam. Aside from also bending an arm of the 4-bar, snapping the mount for the wedge, tearing through the holes for the chassis bolts, and generally just carving that side of v3 up. Elsewhere, there were also large gouges taken out of the rear of the left chassis wall, which compromises the ability to secure the rear panel of the robot. The paint was also scratched. What an asshole!
The thing is, aside from a fat dent in a new lipo I’d bought specifically for the event (disposed of at the event), internally it was untouched. It worked. With the wheelguards prised off the wheels, it drove. The servo still worked fine, the receiver was fine, the ESC was fine, it’s just the chassis it was attached to was all kinds of buggered. Yet it’s a point of pride that I got it into a whiteboard an hour later.
Whilst it has been “repaired” to a functional, driveable state since, these are not repairs that will hold up to any sort of scrutiny, in a competitive situation fighting spinners, so v3 currently sits in retirement alongside v1.
[Punished Frog]
At 16 wins, 12 defeats, and 36 fights over 8 events, it’s definitely the one version with the most longevity out of all the frogs.
In summary: Get 4-bar’d, Son!
