Final image of the robot

With GPS mounted on a carbon rod post.



April 20. 2008 Just before the demonstration day.

Sonar test

Test Video

Enjoy~

Field Test 2 w/ Video

Date: March 16, 2008 (Sunday)
15:00 pm
I conducted new GPS navigation test over the weekend in one of a campus parking lot.
The point of this test was to evaluate newly added navigation algorithm in the program.
Also the field itself is much bigger and not many obstacles placed around.
I solved the heading confusion problem which occurs when the waypoint is placed on the north, by adding two lines of code.

if(Goal_HDG - Current_HDG > 180) D_HDG = Goal_HDG - 360 - Current_HDG;
else if(Goal_HDG - Current_HDG < -180) D_HDG = 360-Current_HDG + Goal_HDG;

The graph shows two different experiment with same waypoint data.
Only difference was the direction and position of the starting point.

At this time I can check the robot draws smoother trackings and does not fell into a heading confusion problem.
For next experiment, I would attach a SONAR in front and test the navigation with obstacle avoidance.

Kyubot overview.

I assembled the body frame on the rc car body to set up for the test.
still looks too complex and should be fixed.

So many lines, make me crazy~

Under testing Kyubot

In one of the roads in the campus.
I was trying to modify way-point data in the SD memory module.


Picture taken by Brad.
3/13/2008, 4:00pm
UF, MAE-C

Field Test 1

The first actual field test held on a parking lot in the campus.
This picture shows the result of GPS navigation.
The length of each small segment is approximately 6~7 meters or 20 ft.
Navigation start from the one edge of the parking lot and finish at one of the slots.

So far, there was no problem at least going from east to west or vise versa, or to the south.
However, going to the north has some problem due to heading confusion at near 360 or 0 degree which both stands for absolute North.

ASCII code

ASCII Hex Symbol 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7 8 9 A B C D E F NUL SOH STX ETX EOT ENQ ACK BEL BS TAB LF VT FF CR SO SI	ASCII Hex Symbol 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F DLE DC1 DC2 DC3 DC4 NAK SYN ETB CAN EM SUB ESC FS GS RS US	ASCII Hex Symbol 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F (space) ! " # $ % & ' ( ) * + , - . /	ASCII Hex Symbol 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 0 1 2 3 4 5 6 7 8 9 : ; < = > ?
ASCII Hex Symbol 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F @ A B C D E F G H I J K L M N O	ASCII Hex Symbol 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F P Q R S T U V W X Y Z [ \ ] ^ _	ASCII Hex Symbol 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 60 61 62 63 64 65 66 67 68 69 6A 6B 6C 6D 6E 6F ` a b c d e f g h i j k l m n o	ASCII Hex Symbol 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 70 71 72 73 74 75 76 77 78 79 7A 7B 7C 7D 7E 7F p q r s t u v w x y z { | } ~ 

Software Architecture of Kyubot

Program flow chart

Picture looks a little crappy but this flow chart represent basic concept of the software architecture of Kyubot.
Remarks
ISR stands for Interrupt Service Routine
Each process enclosed by colored diagram runs independent from one another.

SD memory Card Module

This SD memory module is for programming the waypoints for the robot and data logging.
This module is almost ready to use and just need some wiring and attaching the indicators on the board.

It communicate with MCU using serial protocol @ 19200 bps.

GPS module

GlobalSat BU-353

Water-Proof USB Mouse GPS Receiver - SiRF Star III (BU353)

I finally can get coordinate data from this small GPS module.
This gps module has some pros and cons.
One of the advantage of using this module is that it's relatively cheaper than other GPS module from SIRF.
SIRF is well known for their reliable product line of GPS modules.
However, since this device was designed to be used built in USB serial port, I have to hack it and jump the wire which was connected to the serial input for Serial->USB chip inside the module.

If you want to avoid messing around this, I definitely recommend buying BU-255 model which can be directly connected to serial port.




TECHINCAL DATA OF THE DEVICE
Chipset SiRF Star III (firmware version 3.1.1 with WAAS Support turned on by default)
Frequency L1, 1575.42 MHz
C/A code 1.023 MHz chip rate
Channels 20 channel all-in-view tracking
Sensitivity -159 dBm
Accuracy Position 10 meters, 2D RMS
5 meters, 2D RMS, WAAS enabled
Time 1us synchronized to GPS time
Datum WGS-84Acquisition
Reacquisition 0.1 sec., average
Hot start 1 sec., average
Warm start 38 sec., average
Cold start 42 sec., average
Dynamic Conditions -> Altitude: 18,000 meters (60,000 feet) max
-> Velocity: 515 meters /second (1000 knots) max
-> Acceleration: Less than 4g
Jerk 20m/sec × 3<> Dimension: 53mm diameter, 19.2mm height
-> Cable length: 1.5 meters
Operating temperature -40°C to +85°C

Weekly Report 5

Weekly Reports

Date: 2/12/08

Student Name: Kyuhyong You

Instructors: Dr. A. Antonio Arroyo

Dr. Eric M. Schwartz

University of Florida

Department of Electrical and Computer Engineering

EEL 5666

Intelligent Machines Design Laboratory

Weekly Report 5

What I have done so far.

Hardware

- Motor driver with encoder attached (PID not yet completed)

- Steering Servo initialized and functional

- LCD module initialized

- GPS module initialized – Work needed to decode data from GPS module

l Accelerometer initialized but not attached to the MCU

Software

- Timer interrupt for PWM signal

- Pulse accumulator interrupt for encoder

- SCI interrupt for serial interface to get data from GPS and send data to LCD module

- ATD interrupt to capture analogue signal from potentiometer

- Parsing the GPS data

For next week

Design the cover for the car.

Connect accelerometer module to the board and make functional.

Wait for sonar to be shipped as soon as possible.

Make the SD flash memory card module to be functional.

Weekly Report 4

Weekly Reports

Date: 2/04/08

Student Name: Kyuhyong You

Instructors: Dr. A. Antonio Arroyo

Dr. Eric M. Schwartz

University of Florida

Department of Electrical and Computer Engineering

EEL 5666

Intelligent Machines Design Laboratory

Weekly Report 4

I ordered a GPS receiver from online shop. The receiver is BU-353 Water-Proof USB GPS Receiver equipped with SiRF Star III. It has several advantages. First of all it’s only $37 rather than $100 module. Secondly, its reacquisition time is 0.1 seconds which means it cab refresh coordinates very fast enough to be used for small model car. Thirdly, it has accuracy of less than 5 meters relatively smaller than 10 meter ones.

In cons, it needs to be hacked to be used for my project. It comes with built in USB port which might used for USB-Serial interface. If I can find Rx and Tx line then it can be plugged in SCI port in the MCU.

For next week

Hack the GPS module

Receive data

Find way to use the data in embedded software

Weekly Report 3

Weekly Reports

Date: 1/31/08

Student Name: Kyuhyong You

Instructors: Dr. A. Antonio Arroyo

Dr. Eric M. Schwartz

University of Florida

Department of Electrical and Computer Engineering

EEL 5666

Intelligent Machines Design Laboratory

Weekly Report 3

During the week I’ve been trying to use my new LCD module with backlight. Another one I have been used has serial interface so that I don’t have to be bothered to make I/O interface but now I need to use I/O ports to control this LCD module.

PID controller needs more work. Only the software programming is needed. This can be done in a week.

Now the car has a steering wheel! I found the center position of the period of the PWM signal for the main servo. I attached Hitec HS-5925MG digital servo for doing it and it works pretty well.

For next week

Make the LCD useful for my project

Find good GPS module

PID gain tuning

Weekly Report 1

Weekly Reports

Date: 1/17/08

Student Name: Kyuhyong You

Instructors: Dr. A. Antonio Arroyo

Dr. Eric M. Schwartz

University of Florida

Department of Electrical and Computer Engineering

EEL 5666

Intelligent Machines Design Laboratory

Weekly Report 1

I thought about building a robot embedded on a RC car which can park the vehicle by itself. By searching the internet, I found somebody had done this before and works fine. After looking at those kind of works, I can decide what kind of stuffs needed to make it work.

First of all I definitely need to have a RC car and I found one which is large enough (1/10 scale) to accommodate sensors and boards from the Hobbytown USA in Gainsville. It will cost me about $90.

For the motor controllers, since the motor inside the vehicle is quite not unreliable so I will attach an encoder to feedback the speed of the motors. I found one from the ebay and ordered it on January 16. This one cost me about $34 include shipping.

Stegmann Sick Optical Encoder 1140 PPR

I haven’t decided yet about the sensors but I’m thinking about using two SONARs in front and rear of the vehicle so that it can measure the distance between other cars. I also searched on the web and the prices are about $30 each.

For next week

Order SONARs, Vehicle platform, Battery.

Test the encoder and board.

Make power supply board both for 5v and 3.3v DC.

STEGMAN RD 20 Encoder

Resolution: 1440 ppr (pulse per revolution)
Type: Optical incremental encoder.

I purchased this decent encoder from ebay for $40. which was great deal. Because usually this kind of optical encoders are very hard to get and even more expansive then $100

More info can be found here
http://www.stegmann.com/product/incremental/index.html

Free Accelerometer!

This module is a +-2.5g-10g Three Axis Low-g Micro Accelerometer from Freescale.










This is very small yet sensitive accelerometer from Freescale.
This sensor can detect velocity of each 3 axis x, y, z and output as voltage level signal.
By connecting each pin out to ADC channels in MCU, velocity can be measured easily.

Parts required to finish
3x 1k ohm resister (for each signal output)
4x .1uf Capacitor (noise attenuation)

You can get free sample of this wonderful accelerometer by simply ordering sample from this address. You can order up to 3 items at once.
http://www.freescale.com/webapp/search/MainSERP.jsp?Product%20Type=Products/055M939346251269%60%60Sensors&isComparison=false&SelectedAsset=Orderable%20Parts&pageSize=25&showCustomCollateral=false&showAllCategories=false&columnOrder=Info%21%60Order%21%60status%21%60ReplacementPart%21%60packages_desc%21%60tape_and_reel%21%60app_qual_tier_desc%21%60budgetary_price%21%60REFLOW_TEMP_NUM%21%609_CFLG%21%600000001205%21%600000001644%21%600000001457%21%600000001478%21%600000001498%21%600000001497%21%600000001455%21%600000001454%21%600000001453%21%600000001334%21%60&Order=Order%20sample&fsrch=1&isAdvanceSearch=false&RELEVANCE=true&pageNum=1&assetLocked=false&fromWebPages=false&

However, since they only provide SOIC type package for this kind of item, professional soldering skill is required. SOIC(Small Outline Integrated Circuit) means it is really small!
You may can find this kind of chips on small integrated chipset such as Cellphones. Usually SOIC type chips can be mounted on the surface of board by special machine. It is almost impossible to connect the small pins on the board using regular solder gun. Then how people who doesn't have such machine like me can use this chip?

Here is some tip.
As you can see here, first fix the chip on the board flipped over.
Then connect each wrapping wire to the surface of the chip really carefully.
Once done, use glue gun on it to protect each pin from external damage might broke connection.





Datasheet can be found from the address below
http://www.datasheetarchive.com/pdf/2424781.pdf

Motor Driver

MOTOR DRIVER


This motor driver is array of six LN298N Dual Full-Bridge Driver.
LN298N has fallowing features

- Total DC current up to 4A
- Operating supply voltage up to 46V
- Over temperature protection

Combining by 6, this driver module can draw up to 24A theoretically, and in experiment with 540 DC motor, I couldn't find any problem with it.

Maximum of 12A was consumed when burst start.
The module has 4 inputs, Enable, Direction, PWM and Logic supply voltage Vss
Signal is connected to PWM channel 3 of the MCU
Enable and Direction signal connected to PORTB channel 5 and 4 respectively.

Kyubot is under construction...

As you can see here, Kyubot is now under construction. Each component will be assembled on the top of the car.
So far everything works fine, a little messy though.
02/13/2008