GPS BASED AUTONOMOUS GROUND VEHICLE WITH

ANDROID PHONE INTERFACE AND REAL TIME DISPLAY

By: Kaushal B. PanchalB.E Electronics

Autonomous What Is AuotonomityAuotonomity ?

Its an Integration of many technologies such as path planning, positioning, and orientation sensing along with vehicle control and obstacle avoidance.

GPS and its involvement

Utilisation Of GPS

1.To Find the Real time Coordinates i.e Time, position and fix type data.2.Course and speed information relative to the ground.

Problems faced with data1.NMEA 0183 Standard2.Decoding NMEA 0183

Standard

Interfacing GPS to AVR Micro–controller

The important part of interfacing was done with the help of UART. The GPS was of TTL logic so it was easily complyable

The Problems faced were1.Right Baud rate 2.To get the first data as your Real time co-ordinate data3.Extraction of data from NMEA 0183 Protocol

Before GPS Decoding (Raw Data):

Decoded GPS (Wanted data):

NMEA 0183 Protocol

$GPGGA,035238.000,2307.1219,N,12016.4423,E,1,9,0.89,23.6,M,17.8,M,,*69

Obstacle Avoidance

The Important Topics

Manoeuvrability

Avoiding Larger Obstacle

The Role of SENSORS Ultrasonic Sensors

Image processing

Interfacing to the Micro-controller

Vincenty’s formulaa, b = major & minor semi axes of the ellipsoidNotes:f = flattening (a−b)/aφ1, φ2 = geodetic latitudeL = difference in longitudeU1 = atan((1−f).tanφ1) (U is ‘reduced latitude’)U2 = atan((1−f).tanφ2)Letλ = L (first approximation)iterate until change in λ is negligible (e.g. 10-12 ≈ 0.06mm){sinσ=√[ (cosU2.sinλ)2 + (cosU1.sinU2 − sinU1.co sU2.cosλ)2 ](14)cosσ(15)=sinU1.sinU2+σ = atan2(sinσ, cosσ)cosU1.cosU2.cosλ(16)sinα = cosU1.cosU2.sinλ / sinσ (17)cos2α = 1 − sin2αcos2σm=cosσ − 2.sinU1.sinU2/cos2α(18)C = f/16.cos2α.[4+f.(4−3.cos2α)(10)λ′=L+(1−C).f.sinα.{σ+C.sinσ.[cos2σm+C.cosσ. (−1+2.cos22σm)]}(11)

u2 = cos2α.(a2−b2)/b2 3 A= 1+u2/16384.{4096+u2.[−768+u2.(320−175.u2)]} B= u2/1024.{256+u2.[−128+u2.(74−47.u2)]} 4Δσ= B.sinσ.{cos2σm+B/4.[cosσ.(−1+2.cos22σm) − B/6.cos2σm.(−3+4.sin2σ).(−3+4.cos22σm)]}6s = b.A.(σ−Δσ)α1 =(20)atan2(cosU2.sinλ,(19)cosU1.sinU2α2=atan2(cosU1.sinλ−sinU1.cosU2+(21)−sinU1.cosU2.cosλ)cosU1.sinU2.cosλ)

s is the distance (in the same units as a & b)α1 is the initial bearing, or forward azimuthα2 is the final bearing (in direction p1→p2)

Navigation Algorithm Using Vincenty's formula:

Explanation of the concept and Havershine concept.

Obstacle Avoidance Algorithm

Position Of Sensors

My Prototype:

Front view

Avr (AtMega128)With GPS

Top view with H – Bridge Circuits

Problems Incurred using a 8 Bit MCU and use of ANDROID ANDROID

Large GPS data Resulted in overflow

Looking for an alternative with a High Bit processing

Solutions resulted

Use of High Bit MCU of AVR

Handing over the process to an Android Android PhonePhone

Idea of giving all the Processing to an ANDROID Phone

With the data of GPS having large processing MCU i.e 16 to 32 bit MCU I thought of handing over the data to the Phone as it already has high Bit rate processing MCUWith the help of GOOGLE found some informative siteshttp://developer.android.com/sdk/android-4.0.htmlhttp://news.softpedia.com/news/How-to-Run-Android-Applications-on-Ubuntu-115152.shtml

http://www.vogella.de/articles/Android/article.html

Now the Phone Eradicates the AVR micro-controller Acts in its place as a Arithmetic ProcessorArithmetic Processor and Robot controller.

The Important Questions that remain are:

The Interface between the Phone And Robot

The Interface between Phone and the HOST

Interfacing the robot and the phone:

This time we will use AVR X-Mega series micro-controllers. Using this, we get all the features of the normal 8 bit micro-controller but the unique part is it has aninbuilt USB host. This is used as an way of serial communication between the Phone and Robot. As it is USB communication a standard way of applying it, so it has standard port to use, which makes it cost effective and no other circuit has to be designed.

As we get the information from the Phone we can actually then control the Motors and accordingly manoeuvre the complete Robot . The latter part of bearing calculations and mathematical part is done by the phone, this thus simplifies the Process and the phone can also be used with other Robots as well.

Interface of Phone and Host and Real time Tracking:

Once the Destination co ordinates are provided the robot will begin its path toward the destination. Then if the controller or anyone else wants to see the current progress or even abort the robots action then with the use of the Android SDK we create an application. This application is designed such that the whole information can be relayed to the HOST or the controller via a fast INTERNET.

With the advent of 3G services readily available in India one can sit around in any corner of the world and control the Robot. With simple HTTP (Hyper text transfer Protocol) one can send and receive information to a specific IP(Internet Protocol)Address. As the GPS information is relayed back to the host, using a simple widget using JAVA can be created and this can be routed to INTERNET and the specific Maps of those location can be downloaded and we can view the exact location and progress of the Robot.

Thank youThank you

and and

You Will Never Walk Alone You Will Never Walk Alone kaushalp12@gmail.comkaushalp12@gmail.com