This is not like a Zboard, its way better. There is no lifting of the feet to control acceleration and stopping. It's even better than mine, which I know is better than the Zboard. The only differences are that I have mechanical brakes and freewheel clutches. But for the most intuitive and the ability to be the stealthiest-looking longboard, this wins by a mile.Hummina Shadeeba wrote:The weight sensing is interesting but I think your hands are probably the best place to keep control..
These are regular Randall trucks, nothing fancy about them other than turning down a constant diameter on the ends to give a concentric support for the motor, and of course gluing on the strain gauges. Agreed it would be super awesome to be able to fit the inline motors without any mods to the truck, but the nonstandard profiles of truck hangers complicates things. We came up with a few schemes for this where effectively the motor is supported by the 8mm steel axle instead of by the diecast truck hanger, and which then presents a 10mm axle for the skateboard wheel bearings.Hummina Shadeeba wrote:The motor/wheels are awesome. The simplicity appeals to me. If they could work on regular trucks the world will go ape.
This doesn't have much to do with foot controlled video games, as others have pointed out the analogy of surfing and snowboarding is much more appropriate. Riding an electric skateboard with a joystick control is like riding a surfboard with a hand linkage to a rudder for steering the board. My initial motivation for this project came from riding an original eXskate board and thinking that hands are totally the wrong place to control a skateboard. You really had to train yourself to lean before you pushed the trigger and coordinate all the finger motion and body weight shifting, the brain figures it out like anything but it's not natural.The weight sensing is interesting but I think your hands are probably the best place to keep control..not many people are doing well with foot-controlled video games.
Yeah, if there's ever going to be a deck failure we know where that will be at. But having the display screen inlayed is so cool.The hole for the screen..leaves a big hole in your board. Carbon it up!
Dang, those would have been Ideal for this project. Absolutely ideal. I will order a set for sure for the next prototype, since if we can design an inline skateboard motor that at least works with one model of off-the-shelf truck out there, it would still make it way more accessible to all the people without machine shop tools. Thanks for sharing that.lone_deranger wrote:Although more expensive than Randals (but cheap for precisions) this truck design may require less machining.
A concern with modifying a cast hanger is a loss in the structural integrity - they do have a tendency to banana through normal wear and tear.
In almost all strain gauge circuitry you are running a low pass filter in the amplifier, so any high frequency changes in the strain (as you have indeed on a skateboard truck) are filtered out, and only the average weight remains, unaffected by all the rapid coming and going of bumps in the road. So no there aren't any false readings, and even if there were, they would still have no net contribution since vibration noise averages out to zero.Pediglide wrote: Justin, I have questions about your strain gauges. The way I understand it is that they are measuring the strain on the hanger/axles of the trucks; would this not give a false reading based on the smoothness (or lack thereof) of the road surface instead of the input of the rider?
The Cycle Analyst is configured so that it doesn't command any power to the controllers until the board is actually moving faster than about 2mph. So when you just stand on it, nothing happens, give it one kick and off you go.Also, I'm assuming it does not go in reverse and you mount the board stepping on top of the rear truck first, right? Otherwise, the board will move in reverse or you would have to mount on the board with both feet simultaneously.
It's tempting, and my friend Frank who worked on this many years ago (see start of thread) did his first builds with pressure sensitive resistors. But they aren't nearly as accurate or as linear as strain gauges. You can deal with non-linearity in software, but they aren't very stable or consistent either. I'm sure you could design a pressure sensitive riser that simply installed under the truck and would be a bit more friendly for most people to use, but since I have strain sensors and circuits on hand from other projects this approach was easiest for me.Why not just put Force Sensitive Resistors on the risers?
Thanks, I'll be happy to see more e-longboards of any kind making inroads in urban travel. That would be a future I could live for, so everyone else doing or considering electric longboard builds, Go for it!I can see this setup and interface, add in the ability to control the parameters via a phone app, to be the next e-longboard design best suited for urban travel. Great work.
Pediglide wrote:Justin, thanks for your reply.
I think this truck would be easier to mount the motor on. You can take out the shaft of the motor and replace it with the replaceable 8mm axle. You can also use the other tapped hole to bolt and secure the motor on.
had a chance to ride Justin's board at Maker's faire, there is a delay in the response to prevent the scenario ur describing.I still can't imagine pressure sensing boards being as controllable. What if you were to slip and lean toward the front or back...because you're going 25 on a skateboard, and then you're further jostled by the changes in speed from your foot weighing somewhere just trying to balance yourself?
Yup, I bought a 2' x 2' sheet of 1" thick UHMW and we hogged them out of that. It's not the most cost efficient, we only got 10 pieces out of the $86 plastic sheet, but it means we could viably do a small production run of e-board battery packs which any one can just screw onto their deck like this. The stuff is slippery. I'm not sure if it'd really be wise to do a rail grind on the belly of this board but if you did you'd surely slide pretty fast!torqueboards wrote: What did you use for your battery enclosure? Did you CNC mill the enclosure out of a plastic block?
Well at the very least it should be an option on the table that people have. The belt drive will always be able to get more torque for the same size motor due to the advantages of the gear reduction, but direct drive should have the lowest rolling friction when used as kick board board without power. Both requires some mods to the drive wheel itself, but hopefully those mods are easily doable at home with minimal tools since wheels wear down and need replacement.bandaro wrote:Congratulations justin, you have proved me (and many others) wrong or settled our fears and/or curiosities. An incredible build all around, making me reconsider plans on a board design; "hub motors" for skateboards may be the way.
Unfortunately I am the wrong guy to answer that, there was a time in the 90's when I could land a kickflip but that's about it, right now slides and jumps etc. are not in my ballgame. This is why I'd really like to have some more experienced longboarders try this out for their kind of feedback, not just around the block but on some long trips and descents. When you are really used to a certain vehicle behavior it takes a longer time to get used to and familiar with the nuances of something different, so for a fair comparison they'd really need to ride it for quite a while.So now I'm curious as to it's freeride abilities? It's all well and good to use one for a commute along a road, so how does it survive the sliding and rapid weight shifts when you jump, ollie, ride off curbs, etc? Does the delay in controls allow time for you to slide/land/whatever and continue normally? Can you slide at all or will the wear on the wheels be too great and wear down to the motor too quickly?
I'm with Ben on all these points. Hands free is such a ticket to do rad stuff while riding the board.ZBoardBen wrote:One benefit of weight-sensing boards is the ability to pick it up and still have a hand free (to open doors, your trunk, etc). This is becoming less of an issue now that controllers are getting smaller, but back when they were bigger you couldn't put them in your pocket easily.
Also its nice to have both of your hands free when riding if you need to carry something large. Lastly you don't need to keep track of your controller, or keep it charged. Small benefits for sure but they add up.
If you tried to foot brake with your back foot, then the board accelerates and you quickly learn that's not a good idea. If you foot brake with the front foot, then you come to a stop even faster. We kept telling people at the faire to lean back until they come to a stop and then get off. Most people had no problem with that, but those who were boarders would regardless try to foot brake and run into one of those two issues until it was trained out of them.Justin your build looks awesome btw. I'm curious, what would happen if you tried to foot brake?
That's a good question. Theoretically if your weight is even on both trucks then there is no acceleration, since it's just looking at the force differential. But on the field it's for sure trickier to keep your weight balance in check when turning sharp corners; it takes a bit of practice to pull a 'U' turn on the road and keep your speed consistent the whole while. I tend to lean forwards when turning inwards, and lean backwards when turning outwards, so in one case I tend to accelerate a bit unintentionally and in the other I tend to decelerate. Once I notice what's going on I adjust, but it's still not perfectly smooth all the time.Also, if you theoretically kept your weight distribution completely consistent, and then went into a tight turn, would the board accelerate? That was an issue we had with this one of our original prototypes (http://goo.gl/IEA6Rl) which led us to having discrete sensing areas.