Hi, I am new to the EV thing, I was wondering if anyone has ever seen anyone using a differential with one motor to power two wheels on a longboard? Also what is the best system in an ideal world to power a longboard, Direct drive, belt drive, Differential if it was possible? I want to build a longboard and am willing to take input.
Has anyone tried using a differential?
- Thread starter Slistack
- Start date
torqueboards
1 MW
Slistack said:
How does it work? I would think they would be better sensored than not.
So is this like a 1/5 baja differential? I think this would be great so you could mount a motor and not worry about the deck hitting it.
Although, as torqueboards touched on, you may need a sensored setup AND a bigger motor. May add to the weight too.
BTW, two motors setup per wheel per axle has electronic differential.
Although, as torqueboards touched on, you may need a sensored setup AND a bigger motor. May add to the weight too.
BTW, two motors setup per wheel per axle has electronic differential.
I was looking into it as I want to do it. I found a nice pdf on gear strength calculations, including bevel gears. I haven't had a chance to run the numbers yet.
I think two motors are just right for a board, so one motor front and one back with awd would be really nice. Any pics how you have the gearing setup?
I think two motors are just right for a board, so one motor front and one back with awd would be really nice. Any pics how you have the gearing setup?
it is a 1/8 scale truggy? Differential, also that motor was WAYYY to big for anyone. I fell off of it 2 times cause it had way too much torque. I had to replace a differential after about six months of abuse IE not current limited controller. I really don't think you need 4wd. I made this in September last year and used it in the winter and it was fine. I have been looking for better wheels and I found some i just cant buy them. I have never riden a long board before, so I have no idea what longboarders think of. But when I made this I made it as a pure engineering test. It turned really crappy but it would throw you up a hill at 20mph and didn't complain. I have now moved to a 6354 sk3 motor and I think that is even a little to powerful. Also I have had sensors installed makes a HUGE difference at low speed and in efficiency. When I built this one I had no idea if it would work or not but guess what it does. On this one i literally have a floating differential in its stock case I didn't change any gearing. I don't like electronic differentials too messy two speed controllers and all. I am a mechanical guy not a electrical guy, I dabble but twice as much to deal with no thanks. In my version 3 I am using a 1/8th scale race car differential.
onloop
10 kW
- Joined
- Jun 24, 2013
- Messages
- 600
Definitely thought about this for hours....
I think it is worth testing. But the cost of the diff needs to be less than the cost of buying that extra 1x motor. 1x. Motor mount 1x ESC. To setup a dual drive (two motor) eboard. & if the diff is cheaper than adding the 2ND motor the performance when using a diff needs to be equal or better then the two motor drive.
Otherwise it's not worth it.
Also there is a mechanical loss that needs to be considered.
Also there is a weight factor to be considered.
Also a maintenance schedule for replacing different oil etc.
My conclusion was it's too expensive for no real gains.
I think it is worth testing. But the cost of the diff needs to be less than the cost of buying that extra 1x motor. 1x. Motor mount 1x ESC. To setup a dual drive (two motor) eboard. & if the diff is cheaper than adding the 2ND motor the performance when using a diff needs to be equal or better then the two motor drive.
Otherwise it's not worth it.
Also there is a mechanical loss that needs to be considered.
Also there is a weight factor to be considered.
Also a maintenance schedule for replacing different oil etc.
My conclusion was it's too expensive for no real gains.
Two motors will probably survive longer. If each motor has its own ESC, it should work much like a differential. With brushless motors it's not possible to run two motors off a single controller.
Its like 20 dollars for the diff, and another 60 dollars for another motor and another 60-80 bucks for another speed controller. You will lose the efficiency in your motor controllers more than the gears. so you are looking at another 120 at least in additional electrical components. I think that these crappy Chinese car esc's are not as efficient as you would think. I should know i've blown up at least 4 really nice car and plane esc's. I think its more elegant and put together. I think that the differential will last as long as the battery with the proper speed controller so that it doesn't strip the gear's which is what happens when you apply way to much power. I hope to be making a product someday soon. I hope it will change what people do with long boards. I mean most people just don't have cnc milling machines and beautiful lathe's in their basement. Gears have really good efficiency while belts tend to lose some energy. I don't have all the answers but I am looking for maximum efficiency. right now I am getting about 12wh/mile. Which is pretty darn good but I can increase by at least 20% with some cleverness.
The only way your going to reduce efficiency with a diff is if your just turning circle the whole time. The bevel gears are stationary in a straight line. Generally a larger higher up motor is more efficient than two smaller equalling the same hp, plus one less set of pulleys or gears to loose power on. It has potential.
I am currently on my version 3 board and might finish this week. There are tight tolerances and i screw up, haha. Anyway I will post pictures when i am done but I hope to make something out of it but if nothing comes of it, it will be my last build.
Hummina Shadeeba
1 MW
How bout a link for us? Show us a pic of the one for sale.
I though a belt was more efficient than mechanical diff with a 90 degree angle and teeth.
I though a belt was more efficient than mechanical diff with a 90 degree angle and teeth.
all it is is the differential, and the differential is more efficient then a belt drive, probably like 10% or more.
http://www.ebay.com/itm/HPI-Trophy-Buggy-Flux-3-5-DIFFERENTIAL-Front-Rear-Diff-Pinion-Case-1-8-101077-/371130515940?pt=Radio_Control_Parts_Accessories&hash=item56691a41e4
http://www.ebay.com/itm/HPI-Trophy-Buggy-Flux-3-5-DIFFERENTIAL-Front-Rear-Diff-Pinion-Case-1-8-101077-/371130515940?pt=Radio_Control_Parts_Accessories&hash=item56691a41e4
Slistack, I'm very interested in this as it allows me to use a single long and powerful motor to drive both wheels, put it under the board and still have a differential system. My question is, do you use it for the front truck or the rear truck?
As you can tell, both trucks (rear and front) turn on a skateboard. On the front truck, the outside wheel needs to be faster during a turn. Conversely, on the rear truck, its the inside wheel that needs to turn faster during a turn.
So if i'm going to use this, which truck would benefit from this?
Also, seems this is up your alley, have you looked into transmission/shifters system. I see some at AndyMark.com, but its quite expensive.
As you can tell, both trucks (rear and front) turn on a skateboard. On the front truck, the outside wheel needs to be faster during a turn. Conversely, on the rear truck, its the inside wheel that needs to turn faster during a turn.
So if i'm going to use this, which truck would benefit from this?
Also, seems this is up your alley, have you looked into transmission/shifters system. I see some at AndyMark.com, but its quite expensive.
Similar threads
