Transcript System for Engine Location Of a Web Train

System for Engine Location Of
a Web Train
Paul Wimmer and Adam Weintrop
Dr. Irwin and Dr. Schertz
1/30/06
Outline
• Current position on time line
• Accomplishments of Fall Semester
• Goals for next week
2
Time Line
3
Outline
• Current position on time line
• Accomplishments of fall semester
• Goals for next week
4
Fall Semester
• Designed hardware to use the “2-bit”
method
• Created DCC command program
• Took measurements
• Software flow charts
• Built 1st hardware section for amplification
5
“2-bit” Method
• Because the software only needs to
determine 3 train states
• 0 0
Train off track
• 1 0
Idle state
• 1 1
Train running
6
Differential Amplifier
VDD
5V
R1
R5
1.95MOhm
4
TRAIN
1MOhm
R3
0.6 Ohm
Differential Amplifier
1
2
OUTPUT to comparators
11
Sensing Resistor
R6
1MOhm
U1A
3
LM324AJ
R2
1.95MOhm
GND
7
Results
Situation
Train OFF, power on
Train OFF, power off
Train idle, off track
Train idle, on track
Train ON, power off
Speed 1, train on track
Speed 10, on track
Speed 28, on track
Train running off track
Voltage from DMM
<8.2 mV
<1.5 mV
11 mV
11.5 mV
20 mV
30 mV
80 mV
195 mV
11-12 mV
8
Idle / Off
• Additional gain is needed to help
determine between idle and off track
states
• Software will help determine these states
9
Outline
• Current position on time line
• Accomplishments of fall semester
• Goals for next week
10
Problems to Address for Next Week
• Finish hardware (comparators, interfacing)
• Multiplexing design
• Work on software (hardware I/O)
11