Dual Drive vs Diagonal Drive

lol so are they getting the good one?

ummm ā€¦ no. They can ride the bad one screaming into the gutter.

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I have only ridden Singe drive and DR. I look forward to @roller loaning his DD out for a demo. Rental car antics may begin now! LOL

Here is what I have learned and tinkered with over my many years of racing and 4wheeling: As far as the debate of different distances traveled by the inner and outer wheels and axels one only needs to drive a drag car with a spooled rear & race slicks to completely understand the forces at hand; those cars have locked differentials and any attempt of turning is countered with ā€œI donā€™t think soā€ from the car. So the discussions about different circles traveling different distances and the larger outer wheel having to be larger to travel the same number of revolutions to travel around a outer end of the circle are all accurate. Read em an weep if not back to math class for you non believers. No snake oil here just proven math theory.

Basically and ā€œopen differentialā€ will transfer 50% of the available traction to each wheel. NOTICE I did not say power. IF traction is less on one wheel than the other anybody that has watched ā€œMy Cousin Vinnyā€ knows a car such in the mud with open diff only turns one wheel, the one with the least traction. (path of least resistance)

Limited slip has a clutch pack to try to even out the power going to each wheel but depending on how tightly packed the clutches or how worn they are you will get some power to both wheels but not all and not necessarily all evenly.

Several versions of Locking differentials will transfer power to the wheel with the most traction and allow the faster spinning wheel (typically the outer wheel, if both have equal traction) to accelerate by disengaging the geared locker to allow it to advance which is the clicking sound often heard. if the powered wheel (typically inside wheel) slips both sides will lock to allow 100% of power to be applied to both wheels.

Lots of info available on google researching off roading setups or locking differentials.

SO all skateboard Single, DD, DR and 4 wheel drives I have seen to date are all essentially open differential drivetrain design transferring as much traction as the tires/wheels can to the ground. I have not seen one that has linked the drive wheels together yet. I cannot imagine it would be a smooth carving type design without the ability of the wheels to travel as different rates so they can maintain constant smooth continuous contact with the ground at all times.

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Yet, if the dragster had locked spindles, and turned from a center point on its axle (kingpin) it would be different. I keep trying to explain to people that you need to think of the wheels on one skate truck axle as on wheel. Because it turns from one point. Not two like a car with two spindles. Do this if you canā€™t grasp it. Take a skate truck with wheels on it and, with your hands, put it on the floor and roll it around. Now turn it. And roll in a circle and then try and tell me the wheels spin different speeds. One skate truck with two wheels= one wheel

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Interestingā€¦ i am going to put tape across both rear wheels and test the theory. I would think the outer wheel would turn a little more but not as much as a carā€¦

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In my own mind I think I just debunked my theory anywayā€¦When you turn the truck one wheel will spin backwards,I hate my mind.

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When I turn the truck with wheels, one wheel runs forward and the other one turns backward, like you realised. Obviously this wouldnā€™t work if they were connected by an axle and no diff.

Now look at below diagram. Its a skateboard taking a turn. Are the inner wheels on a smaller radius than the outer wheels ? Yes. Can the inner wheels be spinning at the same rate as the outer wheels ? No. Why ? Because within the same timeframe, the outer wheels need to cover a greater circumference than the inner wheels

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Test done. Inner wheel definitely spins slower. So traction control on vesc fixes this then? Or does it do the opposite and tries to keep them spinning at the same speed?

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According to Vedderā€™s blog, traction control reduces the torque on the motor that spins faster than the slowest motor, proportional to their speed difference. So the VESC on the outer wheel will give that wheel less torque than the one on the inner wheel. But because the speed difference when turning is extremely small, the drop in torque will also be very small. Now imagine your left wheel hitting an ice patch and slipping. Now the speed difference will be significant and so will the torque drop, thus counteracting that slipping.

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Actually that is pretty much how the new Jeep with traction control works. It uses open differentials but takes signals from the the tone ring in the ABS system as a speed sensor and once it senses a difference between the left and right side it uses the brakes to slow down the faster wheel (usually the one with less traction) bring the pulses to within an acceptable tolerance essentially keeping the wheels spinning at close to the same speed. Electronic traction control/locking differential.

The motorā€™s rotation on a dual drive works like a sensor because the rotating speed can be measured. Instead of the brakes being applied on a car the amount of current supplied to the motor is reduced creating the same traction control effect. I believe this is correct according to what I have been reading.

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Actually thatā€™s pretty much how stability/traction control on most modern cars work. When its snowing, I prefer to switch that off to get a feel for what the car is really about.

I always find a nice open parking lot whenever I got a new car and also tested how it would stop slide and emergency stop. Tough explaining that to cops because we were usually having too much fun. Luckily I was always let go with a warning. Once I set up cones and took the wife to do ā€œtrainingā€ they actually commended me for learning how to do car control BUT told me to wrap it up. Wonder if I could put spikes in my board wheels and do winter cruizing? Now a tracked E-board for winter would be a neat idea. Damm taken: http://www.gizmag.com/ungoverned-powered-all-terrain-skateboard/29574/

Dual diagonal using Chinese clone boards

why doesnā€™t that guy just tune the brakes down instead of buying more ESCs?

He has no real idea what heā€™s doing ā€¦ Heā€™s just finding matching parts

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Actually Iā€™m not a complete novice when it comes to thisā€¦

ā€œwhy doesnā€™t that guy just tune the brakes down instead of buying more ESCs?ā€

Itā€™s impossible to. As my videos show the ESCs in these boards are locked down by the manufacturers. They take an off the shelf RC car ESC, alter the acceleration curve to give it a very slow startup to avoid it shutting down/restarting, and then they lock it down so prevent anyone from altering this.

ā€œHe has no real idea what heā€™s doing ā€¦ Heā€™s just finding matching partsā€

Again, as my videos clearly explain, the ethos behind the modifications I show is indeed to find ā€˜matching partsā€™ because I target my videos towards people who:

  1. Canā€™t afford the expensive, higher end models, and,
  2. Donā€™t have much practical experience, therefore the modifications are kept as simple as possible, and to use stock parts as much as possible.
  3. To show that these boards are ā€˜almost thereā€™ and donā€™t need a ton of mods, or esoteric parts, to make them a viable means of transport.

In short, Iā€™m actually helping people get into the electric skate/longboard scene.

Itā€™s a shame some people think this should be belittled rather than recognised.

Itā€™s also a shame that this, my first post, has to be so negative.

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@DocCircuit of the shelf RC car ESCs are programmable. in the same way that the acceleration curve has been modified so too can the breaking curve. I wasnā€™t trying to be negative. simply pointing out a way to make your life easier. to say its impossible is a bit defeatist. nothing is impossible. all ESCs are controlled by a micro controller and by design micros are programmable at worst you might have to reflash. (google ESC reflash) or as is the case with most just a simple programing card will do the job.

ā€œof the shelf RC car ESCs are programmableā€

I repeat: this has been locked down.

ā€œsimply pointing out a way to make your life easier.ā€

I repeat: Iā€™m not a novice at this, but my videos are targeted towards people who are.

Additionally, the advice youā€™ve supplied does not ā€˜make my life easierā€™.

ā€œto say its impossible is a bit defeatist. nothing is impossible.ā€

See answer above.

Also worth noting, in one sentence you say you are trying to make my life easier, in the next you are saying nothing is impossible and my approach is defeatist. Iā€™m confused, should I try the path of least resistance or should I try the impossible? It canā€™t be both.

ā€œor as is the case with most just a simple programing card will do the job.ā€

Not with this ESC. The manufacturers do indeed have bespoke software and specific settings to alter the ESC to cater for the demands of e-skateboards, but they are loath to send it to users (Iā€™ve been in contact with them). So itā€™s a bit pointless for me to tell people to ask the manufacturers for software and settings they are reluctant to supply.

And, as I also say in the videos, this particular ESC is a poor choice for e-boarding, itā€™s so much better to replace the thing in itā€™s entirety.

Then why take them down the paths of non-useable ESCs and just show them ones that will work?

Dont get me wrong but they way you explain things just makes it seem you are just searching around unsure of what ESCs will work

Hereā€™s a cheap esc works used on different boards

And there are plenty others as well and parts etc :point_down:t2: