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

22

OutlineOutline

• Introduction– Project Goal– Background

• Automatic Decoupling System– Train Control– Coupling and Decoupling– Sensor– Decoupling Process

• Recap• Questions

33

IntroductionIntroduction

• Project – Automatic Decoupling System

• The Train – N Gauge Scale Model train– The scaling ratio is 1:160

• Uses for System– Direct– Indirect

44

BackgroundBackground

• Last year – Train control System and location detection

• The Microcontroller to send DCC Signals

55

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