RC Car Active Suspension System - Pt1

In this video we begin the build out of a servo actuated active suspension system for a 1/10 scale RC car. Active suspensions are the forbidden fruit of the motorsports world, banned from Formula 1 and just about every other racing series. So I'm interested in seeing just how effective these systems can be on the performance of a radio controlled truck.
Seriously the best introduction article out there regarding suspension tuning and design:
www.kaztechnolo...
Overview of the state of Active/Semi Active Suspensions and their control strategies:
journals.sagep...
My Github: github.indeter...
My Instagram: / indeterminatedesign
#activesuspension #RC #RCCar #3dprinting #arduino

[@Mr.Wednesday.]

Dude… are you kidding me!? You’re a fkn legend, I’m so going to do this for my XL Super Kraton! Thank you so much for sharing this with us layman peasants 🫡 🙇 🧠

[@iandrake4683]

I've been noodling an active suspension system for my kid's stroller (we'll be living on a dirt road soon). I had imagined creating and training an ANN to do the control, which seemed like a good fit, since I have no idea how to do it deterministicly like you propose.

[@IndeterminateDesign]

That would really cool. I’ve just started to see a few people trying to use neural networks or genetic type controllers. I’ll probably be going over controller strategies in the next video. Some of them are very simple to implement, like the skyhook approach which is focused on comfort so it would be good for a stroller. You could still use a neural network to tune it.

[@jesushinojosa5163]

What controllers do you have in mind?

[@CDRaff]

IDK why those bastards at KZbin hid you from me for so long, but damn this channel is good. Only 6k subs is downright criminal.

[@IndeterminateDesign]

Thanks! I just do it for fun really. The algorithm is fickle sometimes.

[@Mr.Wednesday.]

Right?? Fuckers 🙄 This dude is FYERRR!, Elon needs to make YT his next freedom task

[@clubcyberia8572]

i had to watch this twice.. i kept getting distracted by the RC10 and the nova esc. i like this approach, and i want to do something like this to the axial crawler

[@IndeterminateDesign]

Yeah, I felt bad using it but it had been in a box for like 20 years so I figured it was a good excuse to get it running again. A scale crawler would be a great application and you wouldn't be having nearly as many high speed bumps for the servos to deal with.

[@falkgerbig7787]

The target direction is very interesting to me. We should note that with this servo neither the damping nor the spring stiffness are influenced, only the preload of the spring. This can be used to correct the neutral position of the vehicle or the ratio between positive and negative suspension travel. For example, the changing payload on a motorcycle or the roll angle of a car in curves can get equalized. Therefor only a misalignment is compensated, the driving behavior itself is not influenced at all. For lower air resistance, the ground clearance can be reduced or increased for off-road driving.

[@bytesandbikes]

Cool project. Thanks for sharing!

[@Casey_Schmidt]

This is a cool project! I understand the mechanical side fairly well but the control strategies and software go far beyond my training, education, and experience. But then again, that's why I love watching this stuff! Have you considered collaborating with another creator on youtube to spread some of the tasks for a project like this?

[@IndeterminateDesign]

I haven’t thought about a collab, that would be interesting. Luckily through the F1 gearbox project, I have the contact info for some controls engineers if I get stuck. Hopefully this project can demystify these types of suspensions, because the theory is simple but the implementation is a black hole.

[@MSportsEngineering]

This is awesome. I had to change my pants after you talked about building a shaker rig.

[@davidgekler]

awesome engineering!

[@IndeterminateDesign]

Thanks!

[@ayushkaiwart2451]

Great idea to work upon.👍

[@skippityblippity8656]

Amazing

[@christianaranas5981]

This project is so awesome!! Could you please share any resources or books regarding how you learned to design the suspension frame? I.e. the arms, linkages, etc. I simply want to understand more about it 🙂

[@IndeterminateDesign]

I did a lot of googling, but this article is a great overview of active suspensions. journals.sagepub.com/doi/full/10.1177/1461348419876392 As far as the linkages, they are of my own design. If you want to learn more I highly recommend downloading Fusion 360 and going thru the tutorials. They give you a solid understanding of CAD. Also for the suspension design I studied a lot of FSAE cars which are student built race cars. They typically have complex suspension systems and some even use active suspensions.

[@ighwannawaoui8699]

Amazing project. I'm a student in a technological school and i wanted to do a project on suspention system for car and your car is very innovative. I want to make my suspension similar to yours without having to radiocommanding it. Thing is I have no basic knowledge in this kind of system. Do you have any advice to build such a car. Especially how to build what you did on the damper of the back wheels? Excuse my english, i'm french

[@IndeterminateDesign]

Thanks! I can't tell you the best place to start, but I can tell you how I learned about active suspensions. I did a lot of googling of white papers and doctoral theses about active suspensions. What I learned from these papers led me to additional information. Unfortunately there's not a single complete source for active suspensions as much of the knowledge is kept proprietary by companies with active suspension products. I don't know about your background with electronics, but I recommend trying some simple projects with Arduino to learn how to control sensors and servos. The Arduino ecosystem is relatively easy to use and there are lots of people online willing to help. The suspension on the rear of the car is called a rocker style suspension. If you look on wikipedia look at pull-rod or push rod suspensions. It allows for a different ratio of movement between the servo and the damper/spring.

[@CircsC]

FWiW I think trying this on a 4wd vehicle might actually be easier given the typical geometries. Any chance you enjoy RC rock crawlers? This would be a MASSIVE advantage for a crawler.

[@IndeterminateDesign]

Yes, I’d love to try this on a crawler (If I could convince the wife to let me have another RC). The slower speeds would be perfect for the servo actuators and I’d love to try individual wheel drive.

[@scottduckworth3299]

This is fantastic! I had this idea of active suspension (though I didn't have a name for it) back in the late 90's for passenger cars but my high school teachers thought it was infeasible at the time. I should have ignored them. I even had one of those RC10T trucks back then. I'm now working on making an autonomous RC car for fun (blog.rcbot.racing/). Maybe I'll add active suspension to reignite my unrealized teenage dream. I've already got an IMU in there so it wouldn't be that much of a stretch.

[@IndeterminateDesign]

That's an awesome project. Electronics have come such a long way in the past decade in terms of both processing power and ease of use. I hope to someday make my own autonomous RC car. I've always dreamed of building an RC car so fast that a human couldn't drive it.

[@litarea]

Where do you get the little bolts/nuts that hold the linkages together? Been looking for an assortment of small hardware like that to complement 3d printed parts and haven't run across anything too enticing.

[@IndeterminateDesign]

I buy the assortments of m2 thru m4 from Amazon, usually about $20 for 1000 pieces. You can get them even cheaper thru aliexpress but the shipping can be a long time.

[@eldhocheriyan8686]

can you please share circuit diagram and program

[@IndeterminateDesign]

I don't have a circuit diagram and the code isn't very stable or organized. I will continue to work on this and someday I will release a full working controller.

[@Firashelou]

Great job! I would like to ask you about the battery, how many mAh is it? It looks big

[@IndeterminateDesign]

It’s a 5200mah 2S. It’s probably overkill, but all the servos could pull up to 10-15 amps.

[@Firashelou]

@@IndeterminateDesign yes you are right it could happen, i will have to decide for my car which battery i must get because i have like 6 servos 3 big ones (2 for braking rear and front and 1 for steering) and 3 small ones one of them for throttle and 2 additianal micro servos) i think i have to get the 5200mah 11.1v, what do you think?

[@IndeterminateDesign]

I’m not sure, I’m kind of new to the modern RC cars. A lot of the crawlers will run a separate 2S lipo without a BEC and directly power the servos with 7-8volts, but I know a lot of servos can’t take the voltage.

[@Firashelou]

@@IndeterminateDesign so we are both the same :) yes you are right servos are around 7.2 max not sure if there is higher, for my project i decided to place many BECs with each bek around 3A and there is one 8A for bigger servos

[@DarthOggi]

@@Firashelou The Capacity of the Battery more or less only determines how long it will deliver the needed power, to find out how much current you can draw you have to look at the discharge rate which is normally written in C for Lipos which means how many Multiples of the batteries capacity you can draw. If the Servos don't do a lot of hard work I would say that 1 amp for micro servos and 3-4 amps for normal sized servos is a good starting point. Of course you can always run a lot of high amp becs for additional safety. One important thing is to remove the positive wire from the escs internal bec to the receiver, if you run an external bec, because else you would have two "competing" voltages on the receiver.

[@fruechtekorb]

Hi hi, I am doing this with a rc tank. I did not wanna bother with a miniature hydropneumatic setup

[@IndeterminateDesign]

Depending on the weight, it’s usually hard to beat electromechanical for RC. A tank with an active suspension would be really cool.

[@fruechtekorb]

@@IndeterminateDesign i was actually just going for attitude contol. (Look up MBT-70) but i really like to see if i can fit some potentiometers to the suspension. Now that you gave me the idea. I was just trying to get rid of some of my left over RC and FPV gear, may sticking some action figure on it and go hatchploring in the garden with the offsping. But I wanted to do somthing different. Well i think i need to get it moving. Anyways i enjoy build, and your content very much. You much more efficient than I am.

[@IndeterminateDesign]

@@fruechtekorb Wow that's awesome. You could definitely make a self leveling gun on the turret too.

[@fruechtekorb]

@@IndeterminateDesign That's the plan, I got some of the MPU9250 for that. And I want to have the counter rotating driver cupola on it was well. That one of the reasons that it takes so long. Everything is really tight. But I am not going to make it who is? :D