Rudder pedals, pendular, differential braking, for flight sim

I bought a yoke and throttle and a rudder but I kind of hated the rudder. It moved on rails and just after cleaning it was OK - but always got dusty and sticky and was never smooth for long. A couple of things got in the way and it was probably two years coming, but here is my rudder. It's a pretty big project, it will take a while to build, but I think it is a very good rudder once complete - it will probably cost around $100 to build but I think it performs much better than anything you can buy for $100 or even double that.

This rudder uses a pendular design, two arms that swing from bearings at the top of the assembly move a rocker at the back of the unit in a rotary motion that turns a hall effect sensor. A set of RC shock absorbers returns the rudder position to neutral if you remove your feet and if you add damping oil, will contribute to damping of the pedal motion. On both arms a rudder pedal can be pushed back to activate the brake on that side, again a hall effect sensor is used; a lever door handle spring returns the brakes to the neutral position when released. The rudder connects to the computer via USB; it is driven by a Raspberry Pi Pico that reads the positions of the sensors and reports them to the computer as a HID device, so no drivers needed.

The central hall effect sensor I used is the most expensive thing in the whole project, it cost US$27 and I had to buy it at Mouser Electronics, probably available at other places too. The manufacturer's part number is 6127V1A90L.5FS and if you search for that you will find it. It is an excellent device but you could just as easily get started with a regular potentiometer, provided the shaft fits (or you design a Potentiometer shaft mate part that does fit) and you might need to alter code if it does not work as expected. Just be sure you pick a linear device not a log (audio) potentiometer.

The base suits me because I use some bolts to attach it to an old shelf, it sits under the desk and does not move. You could easily design a different base to suit your needs, for example putting the pedals at a different height. The pedals are kind of vaguely like I think pedals look but you can easily design and print others, they attach with four M3 bolts to the pedal spindle. You can adjust the angle of the brake position on both sides. You can adjust the angle of the pedal arms by varying the length of the steering rods.

I have printed this in the cheapest black PETG I could buy - you will need about one roll to print all of the parts shown here. You should probably print with at least 0.25 Structural setting (assuming a 0.4mm nozzle) for most parts but for the arms and rocker you may wish to print more carefully. I switched to 40% gyroid fill, 3 perimeters, 0.20 layer height - on the arms you want extra strength (your legs can exert a lot of force) and more detail (the 9/16-20 thread for the bike pedal shafts needs to be clean). Maybe cut off all but the thread section of the arms in the slicer and do a test print to be sure the thread is good before printing the whole thing? Or, use a bicycle crank tap to run through the printed part after printing, maybe your local bike shop will help you out. My MK4S printed a perfect thread and though I have the taps I did not need them.

Note that the arms have a channel running through them for the wires that connect to the brake hall effect sensors - if you print with supports you will not get the wire through! Move the slider down to examine the internal layers in the slicer to see this. If the arm is printed lying flat on the plate with the bearing mount pointing up you should not need any supports. If you feel you must have supports, apply a support blocker to avoid closing up that channel.

Parts needed:

• Printed parts - I suggest PETG or stronger.

• Selection of M3 cap head bolts, I bought this kit

• M3 Nylock nuts

• 4.5x6mm brass inserts for the M3 bolts

• Raspberry Pi Pico (I prefer the Pimoroni version, with a USB-C connector)

• code for the Pico - see this github repo

• Steering linkages - I used these

• 4 x 6807-2RS ball bearings - I used these

• 2 x 6805-2RS ball bearings - I used these

• One set of bike pedals to take the shafts and bushings from - I used "PD-R27" pedals from Aliexpress. There are many sellers, I paid around AUD$13 per set, delivered.

• One rotary hall effect device (Mouser Electronics) OR you could use a cheaper linear potentiometer - know how to wire this and be prepared to adjust code

• Two hall effect sensors DRV5056 - I used the A3/Z3: 50mV/mT sensitivity. You could use others but this will depend on your magnets also.

• Two magnets, 6x3mm cylindrical

• Two RC Shock absorbers, I used these

• Two Lever Door Handle Springs, I used these

• Small amount of perforated PCB prototype board to mount the hall effect sensors

• Wire and Dupont connectors (you could also solder them directly)

• Tools including

  • Hex drivers, ball end is useful

  • Hex nut driver for the Nylock nuts

  • Soldering iron for inserting the brass M3 inserts

  • Knife for cleaning odd filament warts

  • Hot air gun for cleaning up PETG stringing

  • Small amount of grease for pedal shafts

  • 10mm socket + attachments for bolts on pedal shafts 

  • long nose pliers (the ones from the Prusa kits are good)

There are some notes on building and wiring the brake sensing modules here.

If you'd like to see a yoke or a throttle next, let me know! And a follow would be nice 🙏