1. Mid-term Presentation: 28th July 2004
Jing Xiong
Andrew Kwok
Mid-term Presentation: 28th July 2004
Positioning Team
Demetri Spanos
Vijay Gupta
Nicolas Foirien

2. MVWT II / Positioning Team GOTChA 7/1/04
Goals
Functional vision system in lab
Robust positioning solution on rooftop
Technical Challenges
Little documentation for lab vision
Don’t know what’s wrong with vision
- (no BIOS access, no second HD)
- conflicting reports of performance
Finite budget for rooftop positioning
New method must be implementable on bats (size weight I/O)
Approach
Find Steve (in progress)
Collect all vision documentation
Switch back to Win2k
Skyetek developer’s kit
Systematic vision diagnostic (~2 hours, 6th Jul)
Objectives
Identify problem/cause in vision
Repair vision to extent possible
- Maintain current functionality
Identify rooftop positioning system by July 7th (10 cm accuracy)
Order by July 14th
Implement by AFOSR demo, if possible

3. MVWT II / Positioning Team GOTChA 7/28/04
Goals
Functional Vision system in lab
Robust positioning solution on rooftop
Technical Challenges
Interface to vehicle
RS232
weight
size
Update rate / sensor noise
Hard to measure orientation
Objectives
Achieve 10cm accuracy for rooftop positioning system
$25K budget
Implement rooftop positioning in time for RoboFlag Competition
-2 week: purchased system arrives
-1 week: finish rooftop vision implementation
Approach
DGPS dual measurement with our own base station
Kalman filter on DGPS boards (Superstar II Navtech)
Accelerometers

4. Systems Comparison RFID DGPS Vision IR Cost $20 K + $10 K + > $20 K
Accuracy
10 cm
1-10 cm
~ 1 cm
1 mm
Time
weeks
1 week
> RFID
Difficulty
High
Low
Med  High
Update Rate
µ velocity
(~ 5 Hz)
10 Hz
50 Hz
> 10 Hz
Orientation No
Yes
(2 measurements)
On- / Off- Board On
Off

5. RFID Based Positioning System – Feasibility Analysis
Hardware feasibility :
Testing using turn table shows max vehicle speed can be > 6 m/s.
Spacing required for 10 cm accuracy is 10 cm
Multiple tag information doesn’t improve accuracy unless distance of reader to tag is known (possible improvement for future)
Financial feasibility : With budget = $25,000 and 30 vehicles
Possible to tag 21x21 m^2 of floor area with 10cm accuracy
Labor feasibility : Unique numbering, sticking them on the floor
individually : time consuming

6. System Block Diagram -Rooftop DGPS- 7/28/04
Satellites
Other Team
Help!
Base Station
Vehicles
Arbiter
(C2 Team)
Needs Work
802.11
Working
Diff
Corr.
Xi,Yi,θi
Need surveyor
Pos./Vehicle
802.11
Zaurus
RS232
DGPS
Board 1
DGPS
Board 2
(w/ KF)
RS232

7. DGPS Budget Item Unit Price Quant. Item Expense Superstar II DGPS
Receiver/Antenna
165 24
3960
Base Station
1150 2
2300
Development Kit
800 1
GPS/KF Textbook
100
TOTAL
7160

8. Superstar II DGPS A low-cost, small-size DGPS receiver 4.6cm x 7cm
22 grams (w/o antenna)
Can be run as a base-station with appropriate antenna
On-board computation
Serial Port Communication
Within 100m of base station, expect to get 1cm accuracy at 10 Hz
Antenna pair separated by 10cm gives angle to within 10 degrees (worst-case)

9. Agenda for the Remainder of Summer
Acquire materials by 6 Aug
DGPS boards for vehicles
Base stations
Development kit
Software interface for DGPS by 13 Aug
Hardware mounting by 13 Aug
Obtain exact coordinates for base stations via a surveyor by 13 Aug
Gather statistics and characteristics of a Kalman Filter for a DGPS solution
Implement the use of accelerometers in the current vehicles