ROCHESTER INSTITUE OF TECHNOLOGY, DEPARTMENT OF COMPUTER ENGINEERING
With the Heart of an Android
An Android to Android remote controlled vehicle
Independent Investigation
Hangwei Wang hxw3306@rit.edu Required Physical Characteristics Jun Yi Lei Jxl4284@rit.edu Android phones Communication Johnnie Xue Jxx2664@rit.edu Android-Arduino Communication Investigation of the required physical characteristics of the RC car. Investigation of effective and usable forms of the communication between two Android phones. Investigation of effective and usable forms of communications between the Android phone and the Arduino board.
Computer Engineering Design Projects 0306-654-01 Instructor: Dr. Roy Czernikowski Due: January 5, 2011

Table of Contents

1.0 1.1 2.0 2.1 3.0 3.1 4.0 4.1 5.0 Project Overview.... 3 RC Car Mechanism.... 3 Speed..... 3
Testing Strategy of Speed.... 4
Power Consumption... 4 Testing Strategy of Power Consumption.... 4 Weight Capacity.... 4 Testing Strategy of Weight Capacity... 4
Alternative/Decisions.... 4
Figure 1: Connection between motor servo, ESC, and Arduino Board.. 3 Figure 2: E10 DRIFT MAZDA RX7.... 6 Table 1.1: Bobby-Grade RC Car versus Toy-Grade RC Car.. 4
Project/Investigation Overview
To explore the flexibility of the android operating system and android devices, we will design and build a remote control (RC) vehicle using android devices. The goal will be to allow users to enjoy the multiple functions of the RC car incorporating android devices. This investigation attempts to address physical issues with the RC car. The investigation is focused on the required physical characteristics of the RC car such as speed, power consumption, and weight capacity.

RC Car Mechanism

A typical RC car is made of four major components, which are motor servo, electronic speed controller (ESC), receiver, and transmitter. The motor servo is the servo that does the rotation of the wheels; it determines the maximum speed of an RC car. An electronic speed controller is a device that controls the speed of the RC car by turning off or on the DC motor attached to its output. A good motor servo requires a good ESC to control the speed. A receiver receives the instructions from transmitter, and sends the signals to motor servo and ESC to operate the RC car. A transmitter sends the message from the user to the receiver. In this project, the receiver and transmitter of the RC car will be replaced by Arduino Board and android devices to improve the performance of system. The investigation will be focused on the motor servo and electronic speed controller. Figure 1 shows the connection between motor servo, ESC, and Arduino Board in this project.
Figure 1: Connection between motor servo, ESC, and Arduino Board
The speed of the RC car is one of the major concerns for choosing an RC car. Due to space constraints, the speed limitation of the RC car in this project is between 3-10 MPH. Under low speed, the system will gather a better image from the camera on the RC car; meanwhile, the camera will not fall off so easily. 3
Testing Strategy of Speed
The speed can be tested by running the RC car in the testing area with simulated weight. The speed will be recorded, and the performance will depend on how successfully the RC car carried the simulated weight items.

Power Consumption

Both the RC car and the android slave device will consume a moderate amount of power. The average battery life on an RC car will give 15 to 20 minutes of run time with full speed. However, the RC car will run on low speed and will not be constantly running; the battery life on an RC car will be much longer.
Testing Strategy of Power Consumption
The power consumption of the RC car can be tested by constantly running the car with both maximum speed and minimum speed for a fully charged battery. The result should show the upper limit and the low limit of battery life of the RC car.

Weight Capacity

The RC car has its weight capacity; it is very important to investigate the weight capacity of the RC car for this project, because there will be a lot of items placed on the RC car such as Arduino Board, batteries, and android slave device. Nothing can be done if the RC car is not moving. Knowing the weight capacity of RC car will minimize the risk caused by overloading.
Testing Strategy of Weight Capacity
The testing strategy of weight capacity is exactly the same as the testing strategy of speed; however, the performance is determined by the maximum simulated weight on the RC car.
5.0 Alternative/Decisions
Hobby-Grade RC Car Toy-Grade RC Car Speed 5MPH to 50MPH 1 MPH to 3 MPH Weight Capacity High Low Power Consumption High Low Quality High Low Flexibility Easy to Modify Hard to Modify Price $100 - $900 $10-$40 Electronic Speed Controller Yes Usually No Table 1.1: Bobby-Grade RC Car versus Toy-Grade RC Car
Based on the information from section 1.1 to section 4.1, an ideal RC car for this project must have low speed, high weight capacity, and low power consumption; however, the weight capacity is fixed on the RC car, and there will be a lot of modification work to be done on the RC car, so the weight capacity and the flexibility will have high priority for choosing the RC car. There are two different types of the RC car available in the market, which are Toy-Grade RC car and Hobby-Grade RC car. Table above shows that the Hobby-Grade RC car is more likely to be the solution. Speed and Power ConsumptionThe speed of the hobby-grade RC car needs to be controlled; the speed is directly related to the motor servo and the electronic speed controller of the car. The motor servo provides the maximum speed of the RC car, and the electronic speed controller provides the speed reduction mechanism of the RC car. Both components are rated by the unit of T (Turn). A turn is the number of times the wire inside the motor is wrapped. Most RC car motors are rated from 10T to 30T. Lowering the turn means higher speed and less torque. The power consumption of the RC car is directly proportional to the speed of the car. The high speed RC car consumes a lot of power. If the speed can be reduced, the power consumption reduces. CompatibilityThe RC car components will be integrated with Arduino Board; it is very important to make sure they are compatible. The Arduino Board controls the motor servo and ESC by generating the pulse-width modulation (PWM) signal, so a PWM controlled motor servo and ESC is required for this project. Tips from Previous Senior Design ProjectIn the CE Design Project - Wi-Fi Based Remote Exploration Vehicle (Spring 2009), an RC car with 20T was used. This shows that any RC car with 20T+ should be usable for this project, because the testing constraint of this project is the same comparing to the project, Wi-Fi Based Remote Exploration Vehicle. Alternative: Figure 2 shows a sample of the Hobby-Grade RC car with detailed specification that can be used in this project; it has 27T motor servo and 27T ESC. Both motor servo and ESC are PWM controlled. The speed is relatively low comparing to other Hobby-Grade RC car; and with adjustable motor, the speed is more likely to be reduced. Since the speed is low, the power consumption is also low. It has roomy space to put all required components on it. Overall, it is perfect RC car to be used in this project.

Figure 2: E10 DRIFT MAZDA RX7
Item Specification: Price: $199.99 This is the 1/10 scale electric powered, radio controlled, ready to run HPI E10 on-road Mazda RX-7 Trueno Drift Car. Length: 14.8" (375mm) Width, Adjustable: 7.32, 7.56, 7.80" (186, 192, 198mm) Height: 4.25" (107.95mm) Chassis: Bathtub type 0.078" (2mm) thick with quick change battery holder and adjustable motor and radio equipment positions to easily convert from street/touring to drift driving with no extra parts to buy Drive: Four wheel shaft Radio: HPI TF-1 AM pistol grip radio system with RF-1 receiver, SF-1 steering servo Electronic Speed Control: EN-1 with reverse Motor HPI Saturn 27T 540 size Shocks: Composite bodied Gearboxes: Closed Differentials: Front and rear bevel-type Transmission: Single-speed Tires: T-Drift 2.48" (63mm) diameter, 1.02" (26mm) wide Wheels: Six spoke, chrome Gram Lights 57S-Pro 2.08" (53mm) diameter, 1.02" (26mm) wide Bumpers: Front, foam Body: Pre-painted Mazda RX-7, adjustable body mounts to accomodate a large variety of touring car bodies Suspension: Full-time independent Caster: Non-adjustable, caster/toe-in refers to the angle of the front suspension when viewed from the side of the car in relation to the chassis Camber: Non-adjustable, camber refers to the angle of the tops of the tires from vertical when viewed from front or behind vehicle Steering: Bell-crank type with servo saver INCLUDES: HPI E10 on-road Mazda RX-7 Drift Car with painted body, radio, ESC, battery, charger, wheels, tires, 27T motor and manual

CONTACT NUMBERS: GERT 0823372749 PAUL 0724351122 www.ermr.co.za E-mail: info@ermicroracers.co.za
CATALOGUE SUMMER 2011 At East Rand Micro Racers we cater for all hobbyists. From those that just want some fun, up to the serious racer. The catalogue only serves as a guideline, as to what stock we carry. We also do special orders if the need arises. So feel free to contact us if you cant find what you are looking for in the catalogue. We do Electric powered Helicopters, Aeroplanes and cars, on and off-road. We also do nitro powered monster trucks, truggies, on-road cars and trainer aeroplanes.

HELICOPTERS:

We carry a range of E-Sky products, from co-axial to full 3D Helicopters, and also spares for all the models. Lama V4 (Blue, silver and orange)

Co-axial (Big Lama)

Belt CP V2 (Full 3D)

Walkera CB180D

Walkera Police Co-axial 53#Q3

Artech Angel

All of the above kits comes RTF (Ready to fly) We do the KDS Fly mentor 3D range of Helicopters, and also the hardware to convert your Helicopter.
For pricing please feel free to contact us.

Nitro Aeroplanes

TH4591-F20M2 READY 40 SC 2.4G M2 (Completely ready to fly)

EP Powered Aeroplanes

ART TECH CESSNA 182

LANYU CESSNA 182

LANYU INDOOR PLANES 3

Radio Controlled Cars:

Electric (Off-road):

Bonzer Cross Tiger

HSP Buggy

HSP Rock Crawler

TRAXXAS BANDIT

TRAXXAS STAMPEDE

Thunder Tiger Tomahawk ST
Thunder Tiger Phoenix RTR Buggy 2.4Ghz 5
Thunder Tiger Phoenix RTR Truck 2.4Ghz

Electric (on-road):

HSP 1/10th scale on-road

HPI E10 Race and Drift

Nitro (Off-road):
Thunder Tiger EB4 S2 / S3 1/10th scale truggy (Pull Starter) Single Speed
Thunder Tiger MTA4 1/8th Scale Monster Truck (Pull Starter/Roto) Two Speed plus Reverse
Thunder Tiger S50 Sledgehammer 1/8th Scale Monster Truck (Rotostart) Two Speed plus Reverse
TRAXXAS Nitro Sport (RWD) Single Speed Ezystart included
HPI Savage Range (3.5, 4.9 and 5.9 XL)
Himoto Nitro range (Mega-P, Viper-X2S, 1/8th Monster truck)
All the Nitro cars comes with Radio (excluding batteries), all you will need is the fuel, batteries for radio and a starter kit, of witch we carry stock as well. The starter kit consists of a Glow plug ignitor, fuel bottle and some tools. We can get a wide range of On and Off-road Nitro cars, the once listed here is just some of our best sellers. The pictures in this catalogue are just for reference purposes, the product may differ in colour. Feel free to contact us for any specials and pricing. We carry a range of spares for the products we sell, and will always make sure that you get the service you deserve.
We are also resellers for YEAH Racing aftermarket parts for most RC cars.
We also do the TAMIYA range of cars and spares. The range includes the Nine Eagle Helicopter and Airoplanes.