HELI-DASHCAM Project - Part 1 (Overview , Theory, Components)

1. OVERVIEW

Because filming videos from the sky provides a viewpoint that can never be seen on ground level, people use drones to record unforgettable sceneries. As an avid cyclist, there were beautiful moments that I wanted to record while riding but couldn’t because I did not have an onboard camera. Also, I thought it would be cool to have an easily portable drone that can sit on my handlebars so I can use it whenever I want. Furthermore, I figured that a drone that has a follow me function is preferable while riding a bicycle in case of an accident. The drone will provide videos from a higher perspective and the police will be able to make more accurate decisions.

DJI Inspire 2 - equipped with a 6K camera, is one of the greatest drones out in the market. Even though it can create Hollywood-grade videos, it may be too big to fit on your handlebars. (picture from https://www.digitaltrends.com/drone-reviews/dji-inspire-2-review/)

The major features of this drone will include:

- 130mm diagonal distance between motors, which will not be bulky

- Can be easily mounted on a bicycle / motorcycle handlebar using a GoPro handle mount

- Can be used as a dashboard camera when mounted on the bike

- Automated follow me function, using GPS signal from a phone

- 2 axis gimbal, equipped with a small action camera (resolution: 1080 HD)

- Regulated maximum height (5 meters)

- Automatically lands on your phone if battery voltage drops low

- Obstacle avoiding using an ultrasonic sensor

- 4cell 1000mAh battery, which will provide enough torque to haul the system and decent amount of flight time (approx. 15 mins)

- Small size controller that can fit in the back pocket of a cycling jersey, while still having a transmitting range of 1100m

- Under $200

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2. THEORY & COMPONENTS

I. How does it work?

1) Follow Me The follow me function allows the drone to literally “follow” the user: more specifically, the user’s cellphone. A phone (an Android phone) sends its location via Bluetooth to the drone. The drone receives this data using its Bluetooth module, and compares the information sent from the phone and the drone’s location. The drone will then adjust its location so the two data is the same.

2) Obstacle avoiding function

The drone uses its ultrasonic sensor to avoid obstacles. The sonar sends out sound waves which bounces off objects and calculates how far a particular object is. If the drone decides an object is too close, it adjusts its throttle to avoid it. The

II. Components

1) Drone

i. Body

*MultiWii: Multiwii is an Arduino-based flight controller, thus can handle various sensors (GPS,Sonar etc) and can be programmed using C++. The MultiWii board is basically a combination of an Arduino Pro Mini and a Wii Motion Plus extension (similar to one installed in the Nintendo Wii Nunchuck).

* Matek 5 in 1 V3 PDB: Includes PBD, BEC 5V output, BEC 12V output, LED light controller, Lost plane finder, and low voltage alarm function

*FDTI USB Module: Used to program the MultiWii board

*I2C-GPS NAV Module: Converts the signal from the GPS module to I2C signal (the signal that the Arduino can understand)

*NRF24L01 Module: Reads 2.4GHz signal (PWM or PPM) from the controller

*HC-SR04: It provides 2cm – 400cm non-contact measurement function using ultrasonic waves. It has an accuracy of 3mm, and has a measuring degree of 15°. The module includes 2 ultrasonic transmitters, a receiver, and a control circuit.

ii. *Gimbal

*Gimbal: I am going to build a light weight servo gimbal to stabilize the SQ12 action camera (size: 1 inch * 1 inch * 1 inch). The FC (MultiWii) will control the gimbal, and power will supplied by the PDB.

2) Controller (transmitter)

I am also considering building an Arduino based R/C transmitter, since most controllers that are out in the market are too bulky to carry in a bicycle jersey. If this does not go well, I will modify a FlySky FS-i6X transmitter and make it small enough to fit in my pocket.

* Transmitter Module: The module above is an amplified module that can radiate more signal, which allows to obtain more range. It transmits 2.4GHz and the receiver module reads it.

* Voltage Regulator: Arduino Nano can be powered by any input voltage between 7V-12V. However, normal input voltage for the NRF24 module is between 2.7V-3.6V. Thus, we need a voltage regulator that can fuel the NRF24 module with 3.3V.

* Charger Module: Allows charging the battery without pulling out the battery and connecting it to a LiPo charger. A mini usb cable is needed to charge the battery.