Webtrain DecouplingWebtrain Decoupling
Adam KadolphAdam Kadolph
EE451/452EE451/452
Bradley University Bradley University
Advisors: Dr. Irwin, Dr. SchertzAdvisors: Dr. Irwin, Dr. Schertz
Final PresentationFinal Presentation
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OutlineOutline
• Introduction– Project Goal– Background
• Automatic Decoupling System– Train Control– Coupling and Decoupling– Sensor– Decoupling Process
• Recap• Questions
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IntroductionIntroduction
• Project – Automatic Decoupling System
• The Train – N Gauge Scale Model train– The scaling ratio is 1:160
• Uses for System– Direct– Indirect
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BackgroundBackground
• Last year – Train control System and location detection
• The Microcontroller to send DCC Signals
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Train LayoutTrain Layout
1. Main Track
2. Bypass Track
3. Switches
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Automatic Decoupling SystemAutomatic Decoupling System
• Starting the system– Train Control– Coupling– Sensors
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Automatic Decoupling SystemAutomatic Decoupling System
• DCC Signals– Receiver boards in locomotive– A packet of data consisting of 42 bits
• Preamble• Address Byte• Data Byte • Error Byte
– Transition bits are rectified for power
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Automatic Decoupling SystemAutomatic Decoupling System
• Coupling and Decoupling– Decoupling Magnet– Train couplers– Relieving coupler tension
→ →
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Automatic Decoupling SystemAutomatic Decoupling System
• Manual Decoupling– Program to remove train cars via simple
controls from a Microcontroller– Train response time– Coupler effectiveness
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Automatic Decoupling SystemAutomatic Decoupling System
• Sensors– Location for Sensor– Detection Angle– Dimensions
• Types to use• Phototransistor• Optointerrupter• Photocell
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Automatic Decoupling SystemAutomatic Decoupling System
• Using the Photocell– 4x Photocells used– Mounting Location– Microcontroller interface
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Automatic Decoupling SystemAutomatic Decoupling System
• Train Detection– Test track– Voltages Ranges become Detection States
Ambient or Nothing State
Coupler StateTrain State
→ →
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Automatic Decoupling SystemAutomatic Decoupling System
• Sensor Programs– Read 1x sensor – Read 4x sensors– Sensor for train control
• Calibration Program– “Smarter” System
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Automatic Decoupling SystemAutomatic Decoupling System
• Decoupling Process– Stage 1 – Remove cars after– Stage 2 – Remove desired car– Stage 3 – Couple remaining cars
→
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Automatic Decoupling SystemAutomatic Decoupling System
• Stage 1 of Decoupling Process– Train approaches sensor– Sensor detects train– Train stops over decoupler– Train moves on past switch
→ →
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Automatic Decoupling SystemAutomatic Decoupling System
• Stage 2 of Decoupling Process– Train reverses – Sensor detects train– Train stops over decoupler– Train moves on past switch
→ →
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Automatic Decoupling SystemAutomatic Decoupling System
• Stage 3 of Decoupling Process– Train reverses – Sensor detects train– Train moves some distance– Remaining cars are coupled
→ →
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Automatic Decoupling SystemAutomatic Decoupling System
• Decoupling Process altogether– Stage 1 and Stage 2 and Stage 3– Switch separates stages– Key press to resume
• Timing issues for Stage 2 and 3– FPGA for DCC signal generation
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RecapRecap
• Key Points– Train Control– Coupling and Decoupling– Sensors– Putting it altogether
2020
Questions?Questions?
The End
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Appendix AAppendix A
• DCC Signals– Preamble – 14 bits– Address, Data, Error – 8 bits each– ‘1’ bit – 60 us low and 60 us high– ‘0’ bit – 120 us low and 120 us high
• 11111111111111 0 0AAAAAAA 0 01DCSSSS 0 EEEEEEEE 1
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Appendix BAppendix B
• Detection State Voltages– Nothing or Ambient State
• 0.0 V to 0.9V and 1.6 V to 3.0 V
– Train State• 3 V to 5 V
– Coupler State• 0.9 V to 1.6 V
• Sensor offset voltages• BL – 0.70 V • BR – 0.48 V• ML – 0.63 V • MR – 0.67 V
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Appendix CAppendix C
• Adding an FPGA to the System– Why?– FPGA board– Train control with VHDL