Posts by Underloaded

    So current plan on the circuitry for the Solenoid looks like this. Its quite bulky but I am sure I can design something compact enough but still be able to fix if a specific component dies.


    I believe 3S 300mAh is enough for the circuit to function 3 minutes. The regulator circuit also turns off the ZVS driver when the voltage set with the potentiometer is met and will only turn on when it "underloads" so itll be at a stable 50V all the time with no overshoots/undershoots and will also save power. Using it to detect signal on only one capacitor bank as they are both powered by the same transformer so both will get (almost) the exact same voltage and current and will cut off the entire ZVS driver so I believe a second Regulating circuit is not needed.

    NCL from the discord server had a brilliant idea to split up the solenoid coil in a number of parallel coils with their own capacitor. That would work a lot better than a single coil. So I'm using two so I dont have to have to complicate anything too much while still getting better performance than a single coil.

    Using relays at each coil so they can be turned on in a sequence like a coil gun with individual stages to hopefully raise efficiency, power and save a small bit of power and not load the transformer as much during a flip. And most importantly to isolate the high voltage side entirely from the receiver and Arduino. If I were to use a thyristor and that blows it would be a disaster. So Relays seemed like the obvious choice.

    Flyback Transformer and ZVS inductor chokes will use Litzwire so they work better. (and ofcourse the flyback transformers output is directly rectified to DC with a full bridge rectifier.


    I wrote capacitor bank but i take it back. i will just use a single 15000uF capacitor at each secondary instead of a bank of 20000uF. I use only 2 capacitors instead of 4. Price is relatively the same and the size and weight is cut in half and i get 18.75J per capacitor before was 25J but its whatever. i am happy with it currently)

    Short link will probably be a screw switch instead so i can just screw it in and discharge both with enough screwing (will be fun to make as the capacitor banks aren't wired together and need to be discharged individually with a single screw) Although before using the short screw/link i could just flip one last time with the ZVS driver's link pulled out and discharge it beforehand into the solenoid so the screw wont be abused as much from the short.

    Arduino Nano is only there to switch on the relays in a sequence for greater power and to cooperate with the receiver- planning to use CH3 switch to trigger the flip on the transmitter. and maybe even using the left knob on the transmitter to make it able to turn on a single coil so in a emergency where instead of dumping all power into a strong flip and missing i can have 2 weaker flips and maybe toss the opponent away from adversity and then charge up for a big flip. Or in self righting issues if the flip is too powerful and just flips back to the same position a weaker flip could help get back on the wheels without flopping around like a fish with no success.

    For the ZVS driver i need a big capacitor on the primary of the transformer and the bigger and beefier it is the faster it'll charge. And i dont want to use something too big so it might charge a bit slower (hence why 2 weaker flips before a big one in emergencies) The gates of each mosfet is connected via 2 diodes to a BJT transistor on the Regulator/Limiter circuit so when the regulator kicks in they will be pulled to ground and turn off.

    For now that is all on the circuit side.

    On adversity all that has been thought of is instead of 2WD ill have 4wd with timing belts and 2 deadshaft wheels. Planning for the chassis to be 3mm thick aluminum or so with HDPE or TPU wheel guards or so.
    For wheels probably diy rubber wheels and maybe cleated wheels aswell

    It's one of these cases where "nothing will happen with the right precautions" is good enough for private use, but as soon as the whole Association gets accountable for what might happen a very tiny risk, however small, gets unacceptable. From what i understood, those of us putting the most volunteering work in (by organising everything and managing the whole stucture) and such would at the same time be those having to take the full consequences even with their private money at risk and such. So... Yeah, sadly not a matter of "taking enough precautions", but more "make it somehow fit inside the rules/paperwork", even if the latter might be less safe for th person handling the bot, it's a lot safer for the Association and its "management".

    Nevermind then. i am staying within the limit as i don't want to make a stupid bot and get the association in trouble because i like what MMM and GRA do and I don't want to mess anything up and put the entire organization at risk. Will be a bit difficult due to this rule but it doesn't matter I will most definitely find a way around and have been exploring a few other alternative 50v capacitor bank ideas and from what I saw one has a LOT of potential to be as good if not better than the original 220V capacitor bank idea. Thank you for going a bit more into depth because I didn't know much anything about the paperwork and I do not want to screw anything up for the organization and get them in trouble.

    The 50V are also due to german paperwarriors, insurances and stuff.

    If i understood that part correctly, anything above 50V may only handled by professionals.

    As the arena marshall is very likely not a professional in that sense, that would be problematic.


    there might be a solution once an extra beetle arena is there and maybe there could be some workaround (like you're being the only one touching the bot and retrieving it with a stick or whatever), but honestly I doubt it. And as cool as the concept is, the hassle and paperwork around it might just not be worth it if it's somehow possible to stay below 50V.

    Oh, I didn't think that German paper warriors and insurance were the things forcing the rule in place. I thought it was at first just a safety precaution for more inexperienced roboteers trying out something new and dangerous and dont really taking in account other stuff that comes along with high voltage and working with it.

    For the workaround, I was thinking of the short link I mentioned and for extra added (probably unnecessary unless Adversity is fully mangled and split in half) protection wear some electrical gloves (i don't think fully solid thick rubber gloves because that would be overkill for 220V which is also inside a box and faraday cage over it all hidden inside the bot imo and i only see it as a must in anything that has reached 1000V to be 100% safe )

    I will be willing to try to keep it under 50V and still work the way intended because paperwork is not really fun. If I can't manage to get it under 50V I will try the hassle of the paperwork in the worst case just to be able to bring it into the arena and see if it can also be as effective as pneumatics and hydraulics.

    We just recently agreed on a voltage limit of 50 Volts because a combat robot may get ripped apart and then high voltage lines would be exposed.

    Might be able to get that working with enough experimentation... I'm fixated on the solenoid flipper idea so I will try to make it work at 50V the way i'm imagining it. Wanted to use 220V as I already have a handful of those capacitors lying around and I could get them for cheaper if anything went wrong and easier to get the required power. Will see what i can do : )
    ditching the idea of adjustability then and making sure it's a fixed 50V driver as it just wouldn't make sense to add something adjustable like that with a lower voltage anymore.

    Hello everyone! I wanted to make this thread because it involves something that "Kinda" breaks the rule of the max voltage inside a bot. I've been looking into these Solenoid Kickers and thought to myself that they might be a good alternative to Pneumatic or Hydraulic Flippers. (I have no experience with them and I have tinkered with high voltage projects in my past in fact they were the thing that started getting me interested in the world of electronics!)

    This is a video I quickly pulled out but is the exact thing I want to do. Charge a Capacitor bank (in the case of the video there's just a big capacitor) and dump all that power into a solenoid.

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    I have thought of a few safety precautions and features I'd put on my bot and I would like to list them and also ask if it is possible to actually allow this bot into the arena and compete Or even be allowed in fun fights due to it breaking the max voltage rule and even having the danger of electrocuting the user while fixing the internals.

    Here are my safety precaution ideas :

    Short link. This would be a link that's wired up to the output of the capacitor bank and will, as the name implies shorts the capacitor bank so there's no way it can charge up. So handling it outside the arena and repairing stuff on the bot is safe

    Power link separate to the high voltage driver. Link ONLY for the high voltage driver so without that link nothing will be connected to any power without that being plugged in first.

    Making it a subsystem unit with its own separate smaller battery and making it easy to tell what's high-voltage and what's the drive system.

    Putting the entire high voltage system in a 3-4mm thick PLA with an aluminum Faraday cage around the entire PLA Enclosure and for it to be connected to battery GND so it can't destroy nearby receivers and general electronics and for the safety of the user so you can't accidentally grab a rogue HV wire lead as its all enclosed in that box.

    For repairs, it can be a unit so it can be switched out to a new undamaged unit to prevent the risk of getting electrocuted.

    Now onto the triggering and features I want/need to add

    For the trigger circuit for the capacitor bank to be dumped into the solenoid, I was thinking of using a thyristor like in this video. (((
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    ))) They use a higher voltage and higher capacity capacitor bank so I'm sure the thyristor could handle the solenoid no problem. The trigger circuit will most likely be a arduino connected to a small receiver and when the value goes from 0% to 100% it should trigger, thinking of using CH3 switch for that.

    For a bit of control and adjustability, I was thinking of Tesla und Mehr's way of controlling his ZVS driver in a way to set a specific voltage. (((
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    ))) I was at first thinking of using an Arduino too and making it adjustable over the knobs on the transmitter but I believe that wouldn't be that secure because i cant code something that precise and if something messes up inside the Arduino or something happens to the receiver it could get stuck at a high voltage position and no longer respond to me lowering the voltage.

    The reason I want it to be adjustable is just for extra controllability and to be able to tune it if the power is too high for example or if the power is too low I can just increase the voltage. The way I would adjust it at the event for extra or lower power is to have a special attachment for my multimeter so it has a XT30 output that will plug into the short link so I can read the voltage of it safely and for me not to have to unscrew stuff and mess around the circuit.

    For the potentiometer I would just incorporate that into the PLA enclosure it'll be in so I can adjust it how I want with a screw without having to, once again pull the unit apart and mess with the circuitry. I can see the problem of the potentiometer slightly rotating during big impacts so I will think of a way to somehow "lock" it in place after adjusting the voltage to my liking.

    More specifics :
    Capacitor bank: 220V 800uF (4 220V 200uF Capacitors in parallel) I might change it to 5.
    Energy: 19.36J (would be 24.2J with 5 capacitors)
    Charge: 176m Coulombs (220m Coulombs with 5 capacitors)
    1.5kg x 10 x 1.3 = 19.5J (should launch a beetle 1 meter into the air)

    I will update and add to this thread more and more during the design process and model so it more clearer what I'm talking about and what I'm doing specifically as I can't really explain stuff that well and I just rely on showing what I have in mind than talking from the top of my head. Looking forward to any replies and will do my best to answer any questions :grinning_face_with_sweat:

    It's a bit upsetting for me to say that Lunaris was kind of a horrible bot, I should've used thicker bigger wheels and added more clearance because I kept getting stuck on the smallest of wood chips/flakes and the weak flipper was also not doing its job. sometimes it wound down but couldn't flip as it got stuck or (what happened most and even visible on the stream) the flipper wound down halfway and then flipped air. (and not like it was nearly strong enough to flip 1.5kg, sadly enough also couldn't self right anymore) if I tried to tune it more than that it would just flip sooner or not at all and if I tuned it less it would just get stuck on the side wedge or bottom. It also didn't help that I couldn't drive well with it while the drive power due to the wheels was not there. Unsure if a V2 will come but there is a chance that later down the line I revisit the idea of a spring flipper and make it better. Currently, I have my eyes on a different type of flipper : )

    Can you tell me the kind of defect? Is it mechanical or the integrated electronic?

    => In my ant-rockeys, the flip-up-system use the electronic of the speed-controller. Therefore the integrated electronic of the servos is not need.

    => If your servos has metal gear and only the electronic is defect: We can exchange our servos. :winking_face:

    I believe its the motor brushes being vibrated out of shape if that makes any sense? like it doesnt short or anything (i used a esc to drive the servo motor itself directly beforehand because it just could not wind down at 5V with the circuitry) and strangely enough the motor works rarely for maybe a pulse but otherwise nothing. Cables were soldered on tight so i am sure its something to do with the brushes- it didnt even get hot a single time. (to be fair it also kinda struggled even with the esc) maybe a current spike killed it?


    = => If your servos has metal gear and only the electronic is defect: We can exchange our servos. :winking_face: =
    Mine are 13kg full metal gear servos- i have 3 of them (just the gearbox) and if you want them you can have them- i have no use for them

    Thank you all so much im really speechless and really thankful- i was over here thinking i just wasted a lot of time into the flipper and programming and everything- it means so much to me i really did not expect you all to be this kind :,)

    In the menue of the forum you see on the right side the field with the double -bubble? It is "Konversation". Please send me a PN (Destination ist "IBF".) Tomorrow I will bring the servos to DHL. (Time ist running...)


    About paying... let's talk next week about. :winking_face: . I don't know the price and the source for delivering. If it is OK for you, you can order two new servos directly to me. Or you can send "my" servos after MMM back to me.


    To your information: The servos did not used by myself. I tested only one servo about "functionallity". No mechanical load and no over-voltage. But the coverage is away.

    I have done it (or so i think... still kinda new with the forum)

    I fear, that I could not participate next weekend in Hannover. :loudly_crying_face: :loudly_crying_face: :loudly_crying_face:


    I have two Power-Servos for my two beetle-weight-bots. If you see a chance for repair of your bot, I could send it to you. (If interesst, please send me your adress asap)

    Thank you so much for offering your servos- it means so much to me. where can i send my adress and more importantly how can i pay you back?

    All my servos are dead so this means its no longer a flipper it'll just be a weird-looking (probably) ineffective wedge with extra steps- I tried so many things to get it to just flip properly again like before, didn't work and all servos decided to bail

    Lunaris is pretty much ready for hannover just that i need to somehow make the servo a bit stronger so its able to wind the linkeage down better, Before i have just taken off the control circuitry of the servo and hooked up a esc to the motor and it worked very well but it came at the cost of my servos dying very strangely. they werent fully dead and still worked when they wanted to but very unreliably. i think maybe vibrations got the brushes bent but i am really unsure...

    To go into more details on whats going on in it just because i have nothing better to do right now :face_with_tongue:

    I am using a 650mAh LiPo and it seems like i went a bit overboard because it can run like 15 minutes without a issue so i am set for a few fights or a long fun fight :smiling_face:

    Using a dual esc from amazon- basically the only ESC i could find that is for a brushed motor and at 3S they work pretty well but i do have some troubles turning after going in a straight line and have to let joystick go to the middle and then i can turn

    If you ever make a spring flipper you should really do your research unlike me- i was thinking that a 13kg servo would be enough but thats far from the truth. You need a way torquier servo or geared motor for a spring flipper- Its my first ever flipper and didnt want to mess with Pneumatics or Hydraulics as i have 0 experience with those. Really hoping that it can atleast be able to lift a bot if anything-


    (V2 will still not use those two or springs either but a diff experimental idea- i can make a seperate thread about it and documenting my experiments and results if anyone would like that, but that will be wayy in the future and hopefully allowed to be able to compete because i havent seen something like it before)

    For the drive motors im using 12V 1000RPM geared motors because i like having a fast bot instead of a slow one- i dont know, faster bots really catch my eye and are more fun to drive imo.

    I'm using a arduino to sense when its armed and hold that state till i flick a switch but the button decided to not work or maybe its the code so i will have to figure that out before hannover-