Showroom Motorcycle 4 DoF Motion sim

awsome build bro.. very professional looking

Thanks man!

I believe I’ve linked it in the thread before, but here it is again any way. It’s a video showing the rig and how it moves. It is from a couple of months ago so a lot has happened in the motion profile since but it shows the basic concept.

I’m currently working on replacing the servos I use for steering feedback with a bigger geared brushless servo. It became quite a large project with a few bits to fabricate before I can properly test it out. Looking forward to having sturdier handlebars.


The new brushless servo reads the input torque too, so maybe I can ditch the whole load cell setup! That would be neat..

The contruction of the new top clamp turned crazy, so now I'm aiming at a CNC solution. I will need to cool down and do something out of wood or similar to evaluate the servo before getting too excited.

Was playing around with haptics in the levers as an addition to the shaker speakers. It really did make a difference for getting a feel of how hard I'm braking and the clutch bite point.



I was also testing some stuff with GameVibe. The idea was to record a wav file of kneepad scraping tarmac and play it through the vibe speakers on my knees when the roll angle would exceed 55 degrees in either direction. Did not seem to get that working, but could be issues with my plugin coding.

Wow, such an awesome project. As of now I never thought about a sim rig for a motorcycle. This looks like a total blast - all the advantage and not dying. A masterpiece!

Thank you very much! It sure is a blast! Doesn’t replace the track bike in any way, but it is awesome nonetheless!

Finally beta21 of GPbikes is released! This opens up for bike motion depending on rider position, a game changer!

Hello, I'm impressed with your project. I have a bike and I understand how difficult it is to accurately reproduce the simulation of riding a bike.

Hello, I was inspired by your example, I also built a layout of my future platform

Hello! Nice to hear, I hope you get to build it!

Spent the past week at the Technical University of Delft in the Netherlands at the Bicycle & Motorcycle dynamics conference. It's a place where industry people and researchers can meet up and present, discuss and test two wheeler simulation in every form.
Presented my motion theories and my steering concept and had great response.
Both researchers and industry people (MotoGP engineers among others) were impressed what Simtools with GPbikes can do as a research tool.

It was a completely crazy awesome week that has given me a lot of motivation to continue developing the sim concept.

The steering it’s the hot potato. I have reiterated maybe six times now and haven’t been able to settle for one solution that has it all.

Did some tweaking and testing of the current hardware today. I’m quite happy as far as electronics and code goes right now. Next step is making it really sturdy.

Finally took the time to figure out the wood CNC mill and managed to make this:


As a proof of concept I’m super happy with it! Remains to be seen if it holds up mounted to the rig.
Next tool to figure out it the lathe for making the axle.. The current one has a 3d printed axle with a threaded 8mm rod inside.

Wow.. That blur effect on the mobile camera was a bit much now that I see it on the computer

Hi, Chris, been following you in the GPbikes forum but didn't find this thread until now, cause i'm starting a "modular" car / bike 2 DOF very simple seat mover. My concept is to make a standard 2DOF seat mover and just swap the chair with bike seat when playing gp bikes. i will also built a bike steering "module" for my G29, witch i could just plug to my wheel to play motorcycle game, and of course gear and rear brake pedal. This will surely be less complex and beautifull as your's but i don't have nor the money, neither the skill to make such lol.

https://www.xsimulator.net/communit...on-platform-for-rfactor-2-and-gp-bikes.18307/

about the best steering system, like you, i found that the gpbikes hardcore mode have been broken since couple of beta, it doesn't feel like the first time i tried it. I've passed lots of night trying to Master it when i found Klax thread about direct steering with a gamepad, the i could manage to make couple of lap but now, i couldn't ever pass 3 conscutive turn.

The big problem i found is how to maintain the leaning when you get the amout you want so it doesnt overlean or hang up the bike, playing with throtlle seems to help as it is more easy to controll the throttle input than the steering input but even if real bike behave like such (hang up when accelerating) it is unnatural to ride that way, and it is imposible on very slow turn where you aren't meant to play with throttle.

In real life when you lean, you counter steer to leaning the bike, move your body to move the bike center of mass and move back you'r steering to continue leaning and the centrifugal force does the rest. And it is really this centrifugal force feedback witch you can feel on real bike that is missing i simulation. Cause this is the only feeling you rely on to jauge if you're in the right speed to take a turn.

May be a motorised harness system like car simulator to emulate fake G force could help but it will take lot of space and structure i think.

Anyway following you're thread give huge motivation to built mine
Keep up the good work

Hey poumpouny! I recognize your name from the forums. Glad to see you here!

Awesome that you're starting a rig build! Looking forward to following your process.

The steering is an issue for sure. Hardcore is not possible since beta19b. Before that it's just immensely difficult and not really representative for how real riding works. Leaning a lot requires effort, but in gpb overleaning is way too easy.

I have thought about the harness thing, but only for acceleration and even that is a little too complex to build. I'm sure I will do it at some point though. The thought of simulating continuous acceleration is too tempting
Too much work going on with the steering right now. But I have a motor that would be perfect for the task and a vest purchased for that purpose. Maybe I'll get inspired some evening..

It motivates me too to see more bike builders in here! High five!

Finally after many obscure obstacles I have the new steering hardware in a working state!

Still waiting for the billet clamps, but the plywood prototype is feeling solid!

I use an isv57 servo for force feedback now instead of the 1:5 RC servos. Code is more difficult, but the performance is a step up for sure.

Hello Chris, I have three questions. 1. Can you explain why you chose a mechanical spring instead of a gas pressure spring to support the motors? 2. How do you calculate how many Newtons the spring should have, do you have a link for that? 3. Are you using two Arduinos and SMC3, or how do you control the motors?

Thank you in advance.

Hello Michail!

1 - The gas springs I found all had some inertia or damping to them. The coil springs are more "transparent". No other effect than supporting my exaggerated mass

2 - No, I just needed to unload the motors and the strongest springs I could find were 400N (about 40kg) at max compression. Still enough to unload the motors enough to let them move even with heavier riders.

3 - I use an Arduino Micro and two Sabertooth motor drivers. The code came from SimuKit.

What are you planning on building?

So I currently have a 2 DOF plus Traction Loss with a Universal Joint for support. I have a fourth motor which I plan to use in the rear like yours for the third dimension heave and to simultaneously ensure traction loss. Additionally, I’m adding another motor for the surge on a linear rail system similar to that from PT Actuator.
All motors are wheelchair motors and have 75 rpm at 24V and 250W. My motors haven’t had a heat problem so far. I guess I’ll continue using 2 Arduino Unos with 5 x BTS7960 and SimTools 3.
I would have used gas springs with 400N force, four of them…