Comments (0)

By Jerome, April 7, 2010 12:11 pm

I was doing technical support on the phone and found this while searching for a customer. http://members.westnet.com.au/page3/picaxe-08m_electric_bike.htm

Remember back when I posted that neat push scooter from Maker Faire. Well, this scooter is the same but electric!

That is a 24V 500W DC motor.

Those are two 12 Volt 26Ah SLA in series for 24V total.

Here is the first model he built. It looks more like the one from Maker faire.

That is a 24 VDC, 18 Amp, 450 Watt DC motor. It has a 4.t:1 ratio so the RPM is around 550.

This is something I would love to build. Yeah more stable at high speed and can handle turns better. It would not be that hard to modify my existing scooter to something like this.

Comments (0)

By Jerome, February 15, 2010 5:03 pm

Hello everyone, I am doing my second intern at www.Solarbotics.com. I brought with me a friend, Rudy to work at SB. We are having a blast here. The weeks go by way to fast!

I just wanted to let you know where my project is going. I broke the motor of my scooter.

I tried to fix it, it did work… for 10 meters when it broke again.

What happen is that the motor lead short circuited and that made the motor heat up a lot!
The vibration of the scooter rolling around made the battery move, thus pulling on the motor driver and unconnected/shorting the motor leads!!

Here is a picture of the power consumption when I had the short circuit. Look at the current, 143Amp!!

This is the motor I might buy

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idproduct=7071

Rated Power: 1580w
Kv: 580rpm/v
Cell count: 4~8 Lipoly

It seems to be a very good candidate for my new motor. My original motor is 380rpm/v, this mean I will go faster!
I will have to wait to got back home to machine a new shaft.

BTW, did I told you I crash with my scooter going 34km/h? I popped a wheelie at 34km/h. The throttle was too sensitive.
I coded a function that would smoothed the input read from the throttle.

On a other note, I am also thinking of getting a motor controller devboard from Microchip.
http://ww1.microchip.com/downloads/en/DeviceDoc/70331A.pdf

Since I have no experience in brushless motor controller, I guest I could start with this neat product.
I has a user interface on the computer so I can see different things about the motor in action.

The PCB looks like this:

Here is the block diagram:

Rudy is working on a Hybrid SAE formula car for is final engineering 2 years project.
http://www.formula-hybrid.org/

He his working on the electric motor drive system and I send him links to lithium battery, MIT go kart, etc. He got really interested in motor driver.
He will help me in the fabrication of the motor controller.

I am also posting this from a desktop wordpress application call Blogjet. It works nicelly for the moment. I am on the free trial. Not sure if I will buy it since there are tons of free one out there. Adding pictures to post is really easy. I will try a posting with w.bloggar too.

http://www.centernetworks.com/wordpress-desktop-blogging
http://www.iamkarthik.com/12-wordpress-editors.html

After posting, I realise that when you click on a image, it link to the the wrong images. I remove the links. We will try again.

Comments (0)

By Jerome, November 20, 2009 8:00 am

I was surfing the web and found this awesome build by some guys at MIT. They made this scooter during a summer engineering workshop.

http://web.mit.edu/first/scooter/

They design and made there own 590W hub motor. Not only one motor but 2 motors! 2 wheels drive scooter!

Me and my friend Jérôme ( yes, one of my good friend is also name Jérôme and we always work together so it is Jérôme² ) are thinking/planning of making our own hub motor for a scooter.  On the BWD scooter website, there is some pretty good info and mathz equations to make your own. Worth looking into.

This is pretty darn sick! Those motors are really powerfull.

Comments (0)

By Jerome, November 6, 2009 8:58 am

I have been searching the web for all kind of interesting stuff and found many good things.

Lately I have been following thread of this forum

http://endless-sphere.com/forums/index.php

This forum is a gold mine for people studying and making electric vehicule.

When searching, I found this thread
http://endless-sphere.com/forums/viewtopic.php?f=2&t=6892

and here is the specific post to download the software.
http://endless-sphere.com/forums/viewtopic.php?f=2&t=6892&start=75#p119810

You can also make some graph  that can be useful.

You can enter all your info about vehicule to get some pretty good result. It give a good idea on the speed you can achieve. I am still skeptic about the distance I can go with the scooter compare to what the simulator told me. That is something I will be testing when I get my new motor.

Member swbluto is the creator of the simulator you just saw. He is also making a electric scooter.

You can follow the thread here: http://endless-sphere.com/forums/viewtopic.php?f=12&t=7638

Comments (0)

By Jerome, October 27, 2009 5:27 pm

When I first installed the motor, I really wanted to test it. I did not have a motor controller so I when to see the guys from www.vamudes.com to borrow one of there 60Amp ESC controller. They did not have “gold bullet connectors” they had normal terminal connector.

I had to remove the “gold connectors” from the motor to change them with blue terminal connectors.

You don’t want to cut those wires, each individual wire strand is covered with thin insulation. The insulation of each tip was remove. So if you cut the wire, you will need to remove the insulation. I recommend high power soldering iron , this  will melt the insulation. I use to take a open flame to burn the insulation… not good, the wire was black and was hard to solder.

The connectors are now crimp to the wire.

I was now ready to test my super scooter.

As we speak,  I have my controller and I soldered back the originals gold connectors.