My Electric Longboard Build – BOM

While I was creating my first build and began to put my first working prototype together, I figured I would document my parts, their prices, and explain why I chose them. I’ve split up the BOM into two parts, the electric longboard components and the board components which are usable on their own for a normal longboard. I decided to go with a single motor design for my first build (it seems fairly trivial to add a second motor in the future) and so far it’s been handling pretty well on hills. The only downside is that sometimes if I lean all the way to the left, the right back wheel comes off the ground slightly and I lose the driving traction. For more info about the trade-offs, check out my previous post.

The way a typical electric longboard works is, you (the rider) use the transmitter to speed up or slow down. The transmitter interacts with a receiver that is hooked up to the ESC (Electronic Speed Controller) which interprets the signal and turns it into a motor signal. The ESC needs to be hooked up to the battery for power since the ESC is what drives the motor. The motor then turns a gear which is hooked up to a belt that will then turn another gear that is attached to your wheel. This is how your longboard will gain movement.

ElectricLongboardDiagram

 

Electric Longboard Components
$70 – 5065 170kV sensored brushless DIYElectricSkateboard motor with 8mm wide and 35mm long shaft
5065 designates the size of the motor and is a common size for electric longboards although they typically have a smaller shaft. 170kV designates the torque the motor can produce (the smaller the number the higher the torque, but the lesser it’s top speed).
motor
$25 – Wiiceiver – (Not needed if you are using the VESC)
 A way to control the input to the ESC coming from the wii nunchuck
wiiceiver
 Has a better feel and is less bulky than a traditional RC controller.wii-controller
$110 + $20 – VESC
I found someone with experience making them and bought one but it needed to be custome made and shipped to me. The extra $20 is because I had to solder on wires and 2200uf 63V capacitor myself.
PCB_Front-1024x683
I used this in the interim while I was waiting from my VESC to be made and shipped to me. With some configuration it turned out to work decently well. I was able to ride it on flat or a slight incline, but with less power and it would cut off if the motor started to draw too much power. 
mambamaxpro
They were a lot cheaper than the 6S1P 5000mah batteries and have decent power and capacity.
5S1PBatteries
DIYElectricSkateboard sells an aluminum part for the motor pulley and I figured that since it’s the part coming off the motor shaft and is only connected by two set screws, it makes sense to get this part made of aluminum to handle the stress.
FREE – 15mm width 36 tooth wheel pulley (3D-printed it myself)
Originally based off a 9mm pulley model, I had to add bigger holes for stronger screws and a couple other changes. I will link to the design I put together for this part once I’ve tested it and made it fit reliably.
OrangatangPulley
$10 – 8mm width 280mm length HTD5 belt
15mm width is better than the 8mm width belt due to it’s wider area and less likelihood of snapping, but an 8mm belt allows for some leeway in alignment.
$5 – 5x M5 x 70mm bolts + washers + nyloc nuts for the wheel mount
These come in a lot more usually than only 5, but it doesn’t hurt to have more just in case.
This works out well and is made of aluminum. This can be replaced with a cheaper non-adjustable mount, but I didn’t like the idea of welding on a mount to my longboard trucks and had not ability to do the welding.
MotorMount
Subtotal: $400

Board Components
I chose these due to the holes in the hub of the wheels that could hold screws in order to mount a gear through.
orangatang_kegel
Due to my choice of wheels, these had to be altered in order to fit them (I used a file to make a bit of room for the screws that hold the gear onto the wheel) If I were to do this again, I might try the Paris trucks since they are more symmetrical.
caliber2fifty
These are some of the better bearings and ride really smoothly.
bonesredsbearings
$100 – Board of your choice
Subtotal: $224

Total $510 with new wheels and trucks on an old longboard
Total $624 from scratch

Node-OpenZWave on Raspberry Pi 2

As a continuation of my Open Smart Hub project I have been interested in adding Z-Wave and Zigbee devices to my supported devices and recently decided to swing for Z-Wave devices first. I bought a Z-Wave Z-Stick Series 2 USB Dongle from Aeon Labs and a simple Z-Wave Door Sensor in order to create the basic mesh network with just two devices.
z-wave-usb-stick

Since the Open Smart Hub is based in NodeJS, it only made sense to search for a Node port of the OpenZwave library. I stumbled upon Jonathan Perkin’s port of it to NodeJS (https://github.com/jperkin/node-openzwave)

Unfortunately, it does not work on Windows, and it seems to be having issues with the latest version of NodeJS… But luckily (or coincidentally) the Open Smart Hub runs on a Raspberry Pi 2 running Raspbian and NodeJS v0.10.28.

After the initial setup of my RPi2 with NodeJS, I got to work getting the node-openzwave module on my RPi2. I was seeing build errors when it was trying to install the module, but found a couple of blogs with information that in order to get it to work I might have to install a couple more tools.

sudo apt-get install build-essential make subversion
sudo apt-get install subversion libudev-dev make build-essential git-core python2.7 pkg-config libssl-dev

After that, it worked and I could call “npm install openzwave” and have it install properly.

Note: If you are interested in using it on Mac OSX, you will need to install the drivers for it. Read more about that process in a previous blog post.

OpenSCAD (Required for the Maker)

Today after finishing the prints for the parts I need for my 3D printer model, I realized I had made a huge mistake. I hadn’t checked the measurements for the holes / rods and since I had gone with the US alternatives to the metric measurements, some parts just wouldn’t work. DOH!

This led to my next realization. The open source community provides the files in easily configurable SCAD files not Autodesk files or STL (STL would have been alot more difficult to edit although it can be taken and printed immediately).

In case you didn’t know, the beauty of SCAD files is that they are essentially programs. OpenSCAD is pretty much the open source standard for creating 3D objects before exporting them into STL format. It is a functional description Red and Yellow Cubes SCADlanguage that dictates the characteristics of the object that allows for reusable variables and one configuration file with the power to change your whole print library! Here’s an example that creates these two rectangular blocks:

If you have been reading my blog posts, I had started using Autodesk Fusion 360 and I thought it was one of the best programs for 3D modeling. Little did I know that the open source community didn’t hand out files consumable in Autodesk and the power behind SCAD files in the open source community is how easily the objects can be customized especially since altering a bunch of STL files would take serious time in Autodesk Fusion 360.