Howto:C172P Cockpit Project: Difference between revisions

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* '''Console'''
* '''Console'''


==== C172 Instrument Panel Project Status Report ====
==== C172 Instrument Panel Progress Report ====
===== December 2016: =====
===== December 2016: =====



Revision as of 12:21, 4 April 2017

The Plan

I am planning to build a complete simulated C172P Instrument Panel with working instruments, gauges, controls and radios, built from scratch, starting in 2017.

This Howto will develop into a detailed project plan for building a C172P Instrument Panel. While not a step by step guide, it will include details on the prototyping, design and building of an instrument panel.

Why am I here?

Cockpit builder Tom Gauvin gave a presentation on cockpit building at Flight Sim Con 2016 at Bradley Field near Hartford Ct. USA. In his presentation, he pointed out that there is no mouse in the cockpit. As a user of a flight simulator, visual and tactile realism is a major factor in the quality of the experience. Having a realistic control panel in front of you or even a whole cockpit surrounding you will bring the experience to a whole new level.

You're invited

I'm finding the project is quite a challenge because I'm working alone at this point.

I'm actively looking for anyone who's going to be actively pursuing building or improving their instrument panel or cockpit in the coming year, 2017.

If you would like to work with me on common goals, consider yourself invited. No experience at any skill is required, but anyone with enough grit to get where they want to go will be welcome.

If interested, you can contact me personally via e-mail. (link)

Specifications

Work has begun on formal specifications for all aspects of the C172 Panel Project. As of 7-Dec-2016, these specifications are being heavily edited and are not ready for use.

Howto:C172P Panel Project - Specifications

I am creating a collection of GIMP Drawings covering each Radio, Instrument and Control. The Drawings are based on various photographs of items in the cockpit, on flightgear fgdata aircraft resources and physical measurements from actual aircraft.

The drawings will be used as input to develop a spreadsheet covering all measurements needed for CAD/CAM designs and tooling.

The spreadsheet is located at https://docs.google.com/spreadsheets/d/13WAzYXTJ5VtTF4HeXYd2oaQTcCOABuSQmISIwCf_kmU/edit?usp=sharing I've made a lot of progress on this spreadsheet. It is nearly complete and just needs to be checked for accuracy. The measurements provided could be used in a script within a CAD program to make it easier to build.

The prototype CAD design is in progress at: https://cad.onshape.com/documents/8809c73453791b9b6cc3e237/w/9ce3211f215b80eb625944c9/e/e989ce51aa08e45e80b73250 . The prototype CAD Design for the panel is nearing completion, but we'll need a way to get from the cad design to software to drive a CNC router. Work on Radios, Controls and Instruments should begin soon.

Contact me if you would like to work this project with me Your level of expertise does not matter, just your willingness to put in some effort on moving things forward.. Callahanp (talk) 18:31, 6 March 2017 (EST)

Design Notes

  • Sim hardware
    • Raspberry Pi3 as master controller
    • Raspberry Pi Nano's, Arduino's, ATMega or PIC microprocessors and peripherals to handle the low level hardware.
  • Switches of various kinds: spst on-off, spdt on-off-on, rotary, fuel selector and a master key switch
    • Sixteen Banks of Sixteen switches
    • MCP23S17 spi Port Expanders - only 2 are needed for 256 switches.
    • raspberry pi nano or Arduino will cycle through the 16 banks every 125 ms and report changes to the master pi to hand off to the simulator
    • ADC port - can handle a multi-position rotary switch if wired to a cascading voltage divider
    • Magnetic reed switches or Hall Effect transducers will be used for the fuel selector
  • Adjusting knobs for instruments, instrument lighting, volume and frequency on radios, throttle, mixture, carb heat, cabin air, cabin heat
    • Potentiometers on an ADC port
    • Rotary encoders on two gpio lines each
    • Magnetic encoder chips on an spi or i2c bus
    • 3d printed knobs and parts for the Trim Wheel
  • Pull switches and dual concentric controls on radios.
    • brass tubing concentric sizes
    • pocket clips and springs from cheap or free pens
    • 3d printed detents and knobs
  • single and dual needles; movable compass rings and other rotating scales
    • Air coils
    • X25.168 stepper motors
    • Air coil or stepper motor driver chips - For example: On Semiconductor CS8190
    • H-Bridge circuit or chip
    • PWM gpio outputs from a raspberry pi 3, a raspberry pi Nano or an Arduino.
  • Needle Indicators and Gauges requiring only 90 degrees of needle movement
    • Meter movements pulled from cheap panel meters driven by pwm outputs
    • Air coils if the meter movements don't do the job
  • the ball on the turn and bank indicator
    • electromagnets driven by pwm outputs moving a steel ball bearing in a plastic or glass tube.
    • damping fluid - if needed
  • white buttons - pushbutton style on some of the radios and autopilot
    • 3d printed - router engraved and painted
  • Numeric displays on the nav/com and DME radios, alphabetic displays on the autopilot
    • Max7219 or Max7221 on SPI or I2c
  • LED indicators on the autopilot, KMA 20 and VOR indicators
    • photo-transparency - for printed lettering
    • 3d printed mask - to separate indicators
    • LEDs - white or orange - low current
  • Flight controls including Yoke, Pedals, Trim Wheel, Flaps Control
    • use Saitek Yoke & Pedals until suitable replacements are designed and built.(2018)
  • Instrument Panel
    • Frame
    • Mounting panel sections
    • Left L
    • Right L
    • Six Pack
    • Switch Panel
    • Right Seat Panel
  • Console

C172 Instrument Panel Progress Report

December 2016:
  • Acquired a raspberry pi, a breadboard and several SPI and I2c chips and a bunch of resistors and capacitors.
  • Constructed an initial prototype of a switch bank using the MCP23S17 chip. A final proof of concept for 32 switches is in the works.
  • Planning a prototype of the circuit needed to drive 7 and 14 segment displays for various parts of the radio stack.
  • Considering the use of magnetic rather than rotary encoders in some parts of the application.
  • Started work on building an air coil that can be used in many of the instruments with rotary dials
  • Ordered a few panel meters to take apart to see if the movements can be used for instruments and gauges where the needle movement is 90 degrees or less
  • Joined Framingham Makerspace. This gives me access to a lathe, 3d Printer, 3d Router and other tools.
  • Work is progressing on building a bench power supply from a spare PC power supply.

Callahanp (talk) 03:34, 7 December 2016 (EST)

January 2017:
  • Contact with a panel builder in Italy
  • Cleaned and organized my garage (otherwise known as the Augean Stables) This took up most of January but I can now walk through the garage without risk to life and limb.
  • Wishing I had more time for this project!
  • Bought "The Art of Electronics", "Learning the Art of Electronics" and "Practical Electronics for Inventors"
  • Wrote a Design Summary "Software and Hardware Requirements for Cessna C172P Flight Simulation Hardware"
  • Finished armature for 2 Air Coils and several Air Coil Housings at Framingham Makerspace, Started making parts for a coil winder.
  • Makerspace closed for most of January due to forced move.

Callahanp (talk) 09:38, 31 January 2017 (EST)

February & March 2017:
  • Makerspace re-opens
  • Researching 3d Cad Solutions
  • Settled on Fusion 360 due to its CAM capabilities
Early April 2017:
  • Mastering Python Scripting for Fusion 360
    • Creating a new Fusion 360 Document
    • Adding Components for sections of the panel
    • Adding Sketches to the panel sections
    • Enrolled in Artisan's Asylum course : Manual Machining and Layout
Next Steps:
  • Adding to the Fusion 360 Python Script
    • Add holes for instruments, gauges and controls
    • Add Extrusions
    • CAM Paths and JOBS
    • Fusion 360 Python Scripts for Radio Face Plates
  • Materials Selection
    • Panel Sections
    • Instrument Bezels
    • Radio Face Plates
Future Steps
  • Design Vernier & Knobs for Mixture Control
  • Switch Bank Prototype
  • Radio Numeric Display Prototype
  • Frequency Adjustment
  • Instrument Adjustment Knobs
  • Instrument Adjustment Prototypes (Incremental and Magnetic Encoding)
  • Volume Controls
  • Push Buttons for Radio Stack