...A new one! [low-cost dirt bike] -- second test video

[sigimem]

It would be like a dream coming true!
But you know, without a small budget you can't start anything new, especially here in Italy.

You can not say that I find your build is one of the most Inspiring works here on endless sphere I have seen so far.
So Maybe this is not such a bad idea after all ?!
But beside that what do you think makes a difference between Italy and a other country in europe in this matter?


Greetings from Germany

 

[BATFINK]

One of the coolest projects I've seen here on endless sphere

Sent using Endless-Sphere Mobile app

 

[silvocross]

But beside that what do you think makes a difference between Italy and a other country in europe in this matter?

Greetings from Germany

Just because the salary for a young mechanical engineer is around 1000€/month, or what about the complexity and the costs to begin a business?
Another funny thing is that here you can not legalize any vehicle if you're a private, but you've to get a TUV licence in Germany, and then convert it in an Italian license.
There are no start-up projects for new ideas, nobody here has a long-term point of view.

The only way to have some kind of success, here, is to born in a very rich family.

Sent from my Nokia 3310 using Endless Sphere

 

[silvocross]

One of the coolest projects I've seen here on endless sphere

Sent using Endless-Sphere Mobile app

Thanks a lot!

But hey, there are many bikes here really impressive!

Sent from my Nokia 3310 using Endless Sphere

 

[silvocross]

some electronic stuff arrived from HK.

2 servos for switching the transmission gears:

battery medic:

400w charger/balancer:

 

[VANDY]

It would be like a dream coming true!
But you know, without a small budget you can't start anything new, especially here in Italy.

You can not say that I find your build is one of the most Inspiring works here on endless sphere I have seen so far.
So Maybe this is not such a bad idea after all ?!
But beside that what do you think makes a difference between Italy and a other country in europe in this matter?


Greetings from Germany

lol! I think in Germany that is a compliment ??? :lol: Add one more mechanical to the list...

I like the idea of mid-mounted motors from about 3 years back now, when my buddy Flo built his very first e-bike. Very ingenious use of the transmission gears inside the frame. The frame looks pretty good, have you said what it is made of yet; steel, chromoly, aluminum? What is your head tube angle?

I have two suggestions:

1. Throw a hub on the bike and start test rides! Let us see how the frame performs.

2. Examine the rear shock angle; it looks as if it is going to be cantilevered, but there is no cantilever? The shock needs to compress in a straight line or it will seemingly bottom out even though it's not fully compressed. Basically the shock should be as close to perpendicular to the rotation of the rear control arm as possible. Does this make sense?

 

[sigimem]

So Maybe this is not such a bad idea after all ?!

lol! I think in Germany that is a compliment ??? :lol:

Do you refer to the part above? I might not get what you want to say.

 

[VANDY]

You can not say that I find your build is one of the most Inspiring works here on endless sphere I have seen so far.

I refer to this statement along with the one that follows...it sounds negative, but I am assuming it is supposed to be a compliment.

I, on the other hand, find this to be an inspiring work. Look forward to updates!!!

 

[sigimem]

Yes what silvocross has done is very inspiring.
With the statement

So Maybe this is not such a bad idea after all ?!

I refered to this

Maybe we can build the Europe Eletric Bike together :wink:

Anyway I hope you have time soon so the bike build goes on keep up the good work.

 

[panurge]

Hi Silvio

Those are impressive steps forward (both the new bike and the Graduate in English), we are all waiting to see your dry servo driven gearbox working!!!
But you are a good guy and I know that study will be your priority now...let me say...just put few minutes at weeks in it, and with your working speed no doubt that you will be working on the next project when lot of us will still playing on our first build....

 

[silvocross]

Hi Silvio

Those are impressive steps forward (both the new bike and the Graduate in English), we are all waiting to see your dry servo driven gearbox working!!!
But you are a good guy and I know that study will be your priority now...let me say...just put few minutes at weeks in it, and with your working speed no doubt that you will be working on the next project when lot of us will still playing on our first build....

Thanks Lorenzo, your support is really important :wink:

The build is still alive, I'm not able to perform mechanical working atm, but the design of the electric/electronic system is going forward.

The idea is to set up an ACTIVE electronic system, instead of the usual passive one.
For example, I'm implementing a smart engine regulation with different riding modes, such as power saving mode, street legal mode, max efficiency mode, race mode etc..
Riding modes will also depends on bike's parameters, so if motor or esc temperature is getting higher, power will be automatically reduced, or if the current over speed ratio is getting too high (an hill?) the system automatically engages a lower gear, and so on..
Also the bike lights will be controlled via software.

INPUTS:

- ESC thermometer
- Engine thermometer
- Wheel speed
- Direct/inverse current
- Battery tension
- Throttle position
- Other..

OUTPUTS:

- Servo 1 control
- Servo 2 control
- ESC control
- Lights
- Other..

A 128x64 backlit LCD will display all the riding infos, such as speed, temperatures, power, autonomy etc..
It's the core of the user interface, where the rider will manage the entire bike behavior.
Will be essentially based on my modular LCD driver:

Here you can see the very first sketch, many corrections and refinements are needed yet. :wink:
This will be connected with the LCD driver via a serial communication.

Thanks for following!

 

[crossbreak]

Hi, nice to see your work is passing on! I've got an idea for the servo shift mechanism:

One servo is used for shifter each fork. Each fork could be moved by a spindle, driven by a gear from the servo, turning multiple times per shift. RC servos use a potentiometer to measure position, but can not turn more than ~90 to 180°. This potentiometer could be swapped for a linear potentiometer connected directly to the fork. By adding additional potentiometers at each end of the linear potentiometer you could adjust the end positions. There are similar servo mods out there for other applications, like this one for pulling ropes: http://translate.google.com/transla...epage.t-online.de/servosegelwinde.htm&act=url
This way the accuracy of the servos could be improved

 

[silvocross]

Hi, nice to see your work is passing on! I've got an idea for the servo shift mechanism:

One servo is used for shifter each fork. Each fork could be moved by a spindle, driven by a gear from the servo, turning multiple times per shift. RC servos use a potentiometer to measure position, but can not turn more than ~90 to 180°. This potentiometer could be swapped for a linear potentiometer connected directly to the fork. By adding additional potentiometers at each end of the linear potentiometer you could adjust the end positions. There are similar servo mods out there for other applications, like this one for pulling ropes: http://translate.google.com/transla...epage.t-online.de/servosegelwinde.htm&act=url
This way the accuracy of the servos could be improved

Hi crossbreak,
I'll use 2 servos, but the forks will be completely remade from sketch, to simplify the connections.
For the first tests I'll lock the trasmission on the 2nd gear.

By the way, here's the PCB design of the main system:

Also the firmare is under development, I can correctly acquire data from the throttle pot, speed, voltage, current and temperature from the two thermistors.
I hope to power up the bike in the next week!

 

[jpgey]

Hello, very nice project !
One question: why don't you use electromechanical solenoid instead servo ?
Some hall sensor near the gearing to return the committed ratio.
Is there any characteristic from the gear box ?
Perhaps i'm wrong, a regular gear box is shift up / shift down / standstill ?

Something like this: http://www.speedycom.co.uk/shop/product.php?productid=18779&cat=&bestseller=Y

 

[crossbreak]

a solenoid is heavier than a servo with the same force and needs more power. but this is still a nice find, these solenoids will most likely do constant torque it would make sence to drive the servos in torque mode rather than position mode - or a mix of both, to get a fast and gentle shift. I do shift up most times without clutch when I drive my 650cc enduro, it works fine as long as I give the shifter a constant force, while closing the throttle - just fast and gentle of course this needs skill - something the chip has to learn first So good luck with that, i'll try to support if i can

For the first tests I'll lock the trasmission on the 2nd gear.

I guess this needs no software

 

[silvocross]

a solenoid is heavier than a servo with the same force and needs more power. but this is still a nice find, these solenoids will most likely do constant torque it would make sence to drive the servos in torque mode rather than position mode - or a mix of both, to get a fast and gentle shift. I do shift up most times without clutch when I drive my 650cc enduro, it works fine as long as I give the shifter a constant force, while closing the throttle - just fast and gentle of course this needs skill - something the chip has to learn first So good luck with that, i'll try to support if i can

For the first tests I'll lock the trasmission on the 2nd gear.

I guess this needs no software

You're right, a solenoid requires more power, and I need 3 positions for each fork, so I'm not sure a solenoid will be easier then a servo..

 

[silvocross]

Here's the printed PCB:

 

[silvocross]

Slowly, but the project is going forward...... 8)
I'm testing the controller at the moment:

 

[silvocross]

....And a first concept of the user interface (zoom needed):

 

[silvocross]

ok, I finally finished the charger and cables:

 

[silvocross]

ok, finally I completed the first prototype of the controller, I've got a display now.

I need to write so much software yet, but I looks good I think.

 

[jateureka]

Some really great and innovative work!

 

[Whiplash]

Please tell me these will be for sale some time soon!

 

[silvocross]

Please tell me these will be for sale some time soon!

It will be finished soon, then if you would be interested in this I could send you a second prototype.. Which are the requirements you're looking for?

 

[silvocross]

Here you can see a very first alpha version of the controller interface, so many bugs atm.
There are also other functions not implemented yet, and I'll add many animations in the code.

And, at last, I'm sorry for the really bad video quality.

http://www.youtube.com/watch?v=fD0pLX8qzJ8&t=9s