Adding Rumble to your Pedals

Short project, with nice results

5 min readFeb 15, 2022

Summary

Some electronics, a bit of soldering, and 3D printing get you detailed feedback on when your brakes are locking (on the brake pedal) or when your wheels are spinning (on the throttle pedal)

Context

Adding stuff to the rig is half the fun of sim-racing. As such, one is always looking for items to add, things to improve. In this context, a conversation with Mike W set me onto the idea of adding rumble motors to the pedals themselves, as the feedback can be very precise, and felt on the very parts of your body that are causing the situation (i.e. your toes)

My first instinct was to find them available. And they indeed are. You can buy them at Sim-3D and, if you are not DIY-inclined, that is exactly what I would do. As a matter of fact, I tried to…but alas, my pedals were (at the time) not supported. They do support a wide range of pedals, but not mine.

Going the DIY route

I of course hit Youtube and the internet, and I did find a number of worthy sources. There are a number of reviews of the Sim-3D system, which you can find on the page linked above. Then there’s this video, which shows the construction process, and has links for some of the materials needed. I used this video as the basic guidance, and I modified it as needed.

The design

Quite simply, the idea was to have two small rumble motors per pedal, with a 3D mount custom-made to my type of pedals, as well as a box to house the electronics. Each pedal has its own cable, that can plug/unplug from the box. The box connects to the PC via USB and the motors get their power from the wall via a dedicated power supply.

The list of materials

You will need to buy a number of things. I am assuming you have basic tools for soldering, etc, so I will only include the materials for the mod itself. They are:

Arduino UNO — this is the microcontroller that you will connect to your PC. I bought this one ($15)
MotorShield V2.3 — this is the motor controller that connects to the Arduino board, and a power supply to drive the rumble motors. I bought this one ($20.5)
Rumble Motors — these are the stars of the show. I bought two packs of these, so I can put two motors per pedal, but I think that stronger motors might be better. Something like this one. ($9 x 2)
Power Supply — it is best to have a separate power supply, connected directly to the motor controller, for the rumble motors. The one I bought is for sure overkill, and you could get away with smaller ones (less amperage). In any event, this one will work ($21)
Female DC Threaded Barrel Jack Adapter — for connecting your power supply to the motor controller. Check the power plug the supply has, and buy the one that goes with it. For the power supply above (5.5mm x 2.1mm connector) I bought this one ($11). Note: unfortunately, you cannot buy these in one-counts, and so I now have 7 of the 8 unused.
3.5mm stereo 3-pole plug jack socket adapters — to connect the motors, I wanted a cable that can be disconnected from the box. Since I was planning of using two channels for the accelerator and two channels for the brake, I settled on a 3-pin connector, so I can have a common negative and the two positives for the two channels. A typical stereo jack works, and so these female adaptors are to use on the boxes’ side. Bought these ones, ($8)
3.5mm Male Plug 3 Pole connector — and then, to terminate each cable, you need these connectors. Again, only need two, but you have to buy 10 :-). I bought these ones ($10)
4 conductor wire — I only need three conductors, but I found this cable so I am using it for the cables from the box to the motors. Bought this one ($11)

All the prices shown above are as of mid-February 2022 and do not include shipping or taxes.

The electronics

The first step is to solder the headers to the Arduino board itself. easy to do, but time-consuming. Check out this video, for directions if needed. Once you are done, you ought to be able to connect the motor shield on top of the arduino.

Then, prepare the two 3.5mm female jacks, as well as the DC female jack, and connect them to the motor shield.

I used the following wiring for the jacks:

M1(+) to “left”
M2(+) to “right”
M1(-) to “ground”

I did not connect M2(-) as I believe it is common to M1(-) and thus I can use that one. For M3 and M4 I repeated the wiring as above.

Wiring to the motor shield. M1/M2 on the right, M3/M4 on the left, and DC power in the center

The 3D printed parts

A bespoke design for the pedals, a simple box for the electronics.

The finished products look like the pictures below:

And the following super-short video shows them moving.

Tuning/Configuration

I used Sim3D’s configuration video, and default setup which I am documenting below for your convenience.

Conclusions

I have been testing and with the tune above, you can clearly feel when the brakes or wheels are locking, as well as when they are slipping. This is precisely what I wanted. The buttkickers were great but they were not “surgical”. These effects are. Will they make me a better driver? Nothing can :-)