E-Freeboard Freebord Open source Electric Caster

Maybe this pursuit is all about reaching the platonic ideal of a freebord: motorized ripsitk

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wave you seen this?

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Thatā€™s actually pretty impressive! Aside from potentially having the electronics getting taken out by a twig, the design of the swivel arm mounted components is clean seem to work well.

It wonā€™t work with the dual motor on the single wheel, but the inboard mounted motor looks nicely protected from scraping low siding damage.

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What an amazing project, cant wait to see how it turns outā€¦

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I might get a little sidetracked buying a broken leiftech so I can get a feel on the whole electric freebord concept. Would be really good to compare the leiftech system VS what I came up with and VS a normal freebord too I guess.
Putting the 5-X trucks on the leiftech would be fun, might need a big spacer or something.

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I came across someone who was making their own casters that could use wider center wheels, The JMK freeride wheels are actually one of the ones they use so I feel smart that I found those.


The wide center wheels are much better for riding through rocks and over soft ground they say.

I still havenā€™t tried fitting my freebord hangers into some random TKP baseplates I should do that.

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on that note, the otherbord axle extenders seem reasonably durable if the freebord trucks become hard to source.


The relative durability may be driven by the main load being carried by the caster, but Iā€™ll take what I can get.

edit: I just realized that since all your turning is controlled by the caster and carving, your kingpin angle (almost?) doesnā€™t matter, which should open up baseplate options too

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I bet the boardnamics 270mm hangers would be nearly wide enough :rofl: It has 10mm stepped axles so they could be extended super wide with custom axles.

I would really like to just power the two normal center wheels but the slip ring headache is terrible, I will keep thinking about it tho I have a few ideas.

Both one that could be attached to/used with the standard Freebord 5 caster mounts (hopefully 3D printed mostly) and one that would be a completely ground up caster design like VillainousJackalā€™s. I would split that idea into one with a DIY slip ring and one built around a wind turbine slip ring (really hard there is no room so the wheel has to move outwards)

Of course also my E-Caster prototype I will toy around with to see if it will work.

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Some really dope people over at Harfang Wheels! :supervillain:

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Ah cool someone taking inspiration from FRC, my one and only area of expertise :). If you arenā€™t an FRC alum or member/mentor, allow me to impart some wisdom about swerves implementation in FRC.

Swerve drive is notoriously difficult to implement for our robots and teams can (and have) spend thousands of dollars refining, tuning, and implementing their designs over 5+ something years before they reach competition level capabilities. And when they fail, they fail catastrophically, generally leaving the team unable to compete until they can get back to their machine shop unless they have spare swerve ā€œmodulesā€ with them. Also for reference, a team will use 4 (or, in very very rare cases, more) swerve ā€œmodulesā€ per 120ish lb robot.

Not driving the wheel along the lazy-susan axis is definitely going to save you some headaches with striped gears and cut down on your tuning time, but I donā€™t know if the lazy-susan youā€™ve chosen is strong enough (it says its only rated for 150 lbs on the site) especially with the variable of the torque from the motor and wheel applying forces in directions the bearing is not designed to take on top of your weight). If your bearings seize up from weight or shock as youā€™re riding, theyā€™re gonna throw you off. As was mentioned before too- bearings donā€™t like shock forces and the tracks will deform fairly easily from what Iā€™ve seen.

Finally, I know belts are our choice of power transmission here as the standard but I honestly donā€™t know if itā€™s the best bet for you in this application just because of the nature of the drive and I feel like skipping on this drive would really **** some stuff up.

Sorry for the long post this is super interesting and I love the idea of swerve I just had some thoughts I wanted to share with you. I look forward to seeing what you do with the project and Iā€™ll follow along with it!

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Hey man!

Yeah I did 2 years FLL, 3 years of FTC, and 4 years of FRC the latter half as the design and build captain.

I should have mentioned in the post background that I have designed and produced a swerve drive of my own.
https://www.chiefdelphi.com/t/pic-4450-orf-off-season-tribot-swerve/161042
Here is the monstrosity.

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The module is spring loaded so I can tune it to apply whatever amount of force to the ground I would like, Iā€™m hoping less than 150 lb is enough for it to not lose traction when under high torque. The geometry also makes it so the force of driving the wheel on the ground pushes the wheel into the ground further (wants to lift off the ground). At this point I am mostly just hoping it is strong enough, a steel one would be much preferred. Mainly focused on cost for this first prototype.

A properly tensioned belt should be able to take this imo, I can go up to 20mm width if need be.

I have been thinking about driving the wheel through bevel gears which would shrink the whole thing significantly as well as avoid a hole in the deck. To prevent the driving torque from turning the module (although this might not be a real problem because of the caster element) I was thinking of using a coaxial drive with bevel gears so the driving force is split and opposed to itself to cancel out turning forces like a differential swerve. Bevel gears in a high rpm environment is a bad idea though and it would be complicated and expensive.

The more people that talk to me about this the better! Bring it on!

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This dude seems to think any powered caster a copy of the summerboard, and they they would really try to stop me from open sourcing it like assholes.

Any thoughts on this?

My real defense is that if you remove the freebord that it is attached to, the E-Caster is pretty different from the summerboard one. It just happens to be attached to the same thing that the leiftech one is.

update they banned me from the group
image

Would love to hear the logical reason why.

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First they rip Freebord, then bring out the V1 with tons of failing parts, then they cant deliver any spare stuff long time, as i started to advertise on their secret forum some hopups to get the other guys back on board i get some pissed comments of moderators ā€¦ would love to see a non patented and nice working solution for community because the expierence is so freaking amazingā€¦ i totally felt in love with this 3D kind of esk8 ā€¦ wish you the bestā€¦ keep on good work (-;

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I would like to still be in the group so I can share my experience with the V2 and ask questions. Iā€™m going to ask for an explanation and to be unbanned on the condition I donā€™t talk about my DIY electric Freebord.

Shame they have to be dicks to anyone who isnā€™t a blind follower.

Really appreciate your encouragement @NoWind Making my day big time.

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While you are here am I dumb to try to hook up 12S to it?

Or should I stay around 8S? Iā€™m thinking right now Iā€™ll try 10S first.

I have to totally agree with this, the extra axis is unreal to ride with - I love it (but my summerboard is broken right now).

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Thanks my friend, always a pleasure

I switched to Vesc4 before using 8SLipos. Thought about higher Voltage but was afraid because 400kv and max erpmā€¦ generell i dont see advantage with original motors and higher voltage because i never missed topspeed on thisā€¦ still got some turnigy sk3 laying around to replaceā€¦

Whats up with her?

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Ah ERPM I forgot about thatā€¦
I heard people talking about swapping to SK3ā€™s, do they share a bolt pattern?

I also want to remove the whole motor/wheel mount and make a diy version. Iā€™m glad it bolts on instead of being 1 piece.

It arrives tomorrow!

Well, truth is I dont know, could be one of three things. Inside the battery there are three circuit boards, on optical isolator board that controls the LEDā€™s, a Hall PCB that detects a magnet in the battery housing and a discharge BMS. One of them is causing the board to cut out intermittantly, Summerboard have sent me all three boards and I will find out soon.

Itā€™s a great upgrade on the V2, the 12S makes a huge difference

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