Joseph Ravichandran (jpr3 ECE 120), Taiqing Ling (taiqing2 ECE120), Yunhan Fu (yunhanf2 ECE110), Kanad Sarkar (kanads2 ECE 110)
Final Report:
Electric Skateboard Remote Proposal:
Introduction
An important thing to make the electrical skateboard work is the remote control. Thus, in our project, we decide to build a controller. Besides, because people use phones almost everyday nowadays, we also want to connect the phone to the skateboard controller so that people can control the skateboard using a phone so it can be convenient and there can be a double insurance. To achieve this, we’ll need to connect the phone to the arduino through bluetooth and then connect to the skateboard controller via XBEE. We’ll also make an IOS program to realize the control.
Background research:
For this project we looked at the XBEE radios to communicate between the skateboard and the controls. It is a chip small enough to fit into a controller, and it is efficient in communicating with and arduino. We also looked at how to communicate between the Adafruit Bluefruit and an iphone. We also started to look at what other electric skateboards used for their controller design in hopes to 3d print it.
Complete Parts List:
Motor: https://hobbyking.com/en_us/turnigy-g160-brushless-outrunner-290kv-160-glow.html
Batteries: 2x 2200 mAH 7.4V LiPo Batteries
Lillipad (for the remote control): https://www.sparkfun.com/products/12921
Battery Charger: https://www.sparkfun.com/products/10473
Electronic Speed Controller: https://hobbyking.com/en_us/turnigy-ae-100a-brushless-esc.html
Bluefruit Feather: https://www.adafruit.com/product/3406
Pulley conversion kit: https://hobbyking.com/en_us/gear-set-with-belt.html
Motor mount: https://hobbyking.com/en_us/motor-mount-5.html
ESC Connectors: https://hobbyking.com/en_us/polymax-3-5mm-gold-connectors-10-pairs-20pc.html
Small Pulley: http://shop.sdp-si.com/catalog/product/?id=A%206A25M014DF0906
Large Pulley: http://shop.sdp-si.com/catalog/product/?id=A%206L25-040SF0910
Belt: http://shop.sdp-si.com/catalog/product/?id=A%206R25M057090
Parts (Remote)
Input potentiometer
Adafruit Bluefruit (with BLE for connecting to iPhone)
XBEE radio (for communicating to the skateboard itself)
Rechargeable AA batteries
MicroUSB port for recharging
Jumper cables, breadboard, and MOSFETs to create NAND gate
Shell of the controller
wires
Challenges
Connect each parts;
Programming
Assemble the controller
Design
System overview
We’re going to make a controller to control the skateboard. We’re also going to make a program on the phone to achieve operate and record the battery level of the controller and then connect the iphone to the arduino uno. Then, we need to connect the arduino uno to the skateboard controller via XBEE. We also need to achieve distance recording using hall effect sensor and then send data back to iphone. Also, we need to solve the emergency power off of the controller and make a shell of the controller using 3D print.
Electric Skateboard Control System
Introduction:
One of the biggest challenges facing our society today is finding a form of fast, energy efficient and quick transportation that is affordable. Many students find a solution to this problem in the form of a bike, but bikes are bulky and cannot easily be stored. Locking up a bike requires carrying around a lock, and then finding a free space in the crowded bike racks. Then the person has to walk from the bike rack to their class. Our proposed solution is a much more effective method of transportation- one small and light enough to carry into class with you, and powerful enough to rival the speeds of a bicycle while requiring zero effort of the user. Imagine a world in which people effortlessly canglide from class to class without having to lift a foot. Imagine a form of transportation in which turning is as simple as leaning from side to side, and accelerating as simple as pushing a lever. Our goal is to create an electric skateboard that can easily meet the demands of a student on a large campus who needs to quickly get from point A to point B without carrying around large bulky locks or finding a parking spot before going to every class.
Background Research:
The transportation market is currently saturated with various forms of student transportation. Bicycles, longboards, and even other electric skateboards are available. What separates us from the competition is our affordability. The current standard for electric skateboards is the “Boosted Board” which can cost up to $1500. We plan to construct a much more affordable electric skateboard in the $300 to $400 range. While this price tag is similar to that of a good bicycle, our skateboard offers added portability and effortless control. Our skateboard offers the premium experience of effortless control, extreme portability, and security for the same cost as a bicycle.
System Overview:
The central hub of the system will be an Arduino mega that processes the data and performs computations. While we know that this chip is an Arduino and is not a chip of our own construction, we feel that the Arduino mega is the only chip we can trust to reliably and quickly handle important data to deliver a safe and reliable experience. We need a system we can trust when accelerating people on a moving object so that nobody gets hurt due to a glitch or lag in the processor. This chip will have an XBee radio attached to it designed to pair to an electric skateboard remote control, and this connection will transmit data such as encoder data, distance travelled, current speed, and other relevant data. The chip will also communicate over bluetooth with an iPhone for displaying and inputting data in an easy to use touch interface. In a pinch, the iPhone will also be able to be used as a controller, albeit not as precise as the remote. As a side note to the overall system, we feel that an iPhone cannot offer the tactile feedback we want for a reliable and precise input method, and that is why we are going to design our own remote control. The main Arduino will be powered by a battery which is connected to an emergency shutoff switch powered by a NAND gate. The NAND gate will output a 0 when both a constant voltage and an input switch are pressed. The output of this will be used to power the Arduino. Therefore, when an emergency shutoff switch is pressed, the Arduino will physically be shut down, and all power will cease flowing through the system. The Arduino interfaces with the brushless motor over a motor controller. The motor itself will have a Hall effect encoder which is hooked back up to the Arduino to provide motor state data. The Arduino will also control a braking system and an H bridge to control the drive train. Lastly, the Arduino will control an ambient lighting system that turns on when it is dark outside. The ambient lighting system will increase safety and visibility, as well as turn signals and colored LED surround lighting for a coolness factor.
Battery:
9 or 10 cell 35 Volt LiPO battery and charger to power the motor
Voltage step down circuit for powering Arduino chip
Challenges:
The most challenging part of this project will be creating a secure connection between power delivery and the motor, and then converting that energy into motion for the skateboard. We plan to solve this by precisely engineering the most effective method of attaching the motor to the skateboard and wheel.
