Anyone want to help modify a Radio Flyer Model S?

[Fusion]

You guys try Plasti Dip spray on the tires? Might be enough to last a few runs and cheap enough.

 

[buttershrimp]

Still waiting for more parts for my steering linkage.. They were cheap enough and I ordered extras so if one servo doesn't cut it, I can go to a dual approach.

I decided to ditch the stock battery, as much as I like to keep it clean, the BMS board has been a pain to hack. I'll probably end up gutting it and filling it up with cells.

In the mean time, I 3D printed these... They're 4S5P packs made with genuine Tesla cells.
View attachment 293288 View attachment 293287

I got the motor controller hooked up and working with a basic RC receiver. Just need steering now and I can get to programming all the autonomous functions.

View attachment 293289

I'm going to have to find another approach for the tires. Unfortunately my 3D print of the TPU tire failed after 30 hours and going though 1/3 of the spool. The 95A hardness doesn't have enough grip IMO anyway. Softer filaments are available, but they're significantly more expensive.

Sounds like you need some miniarachnids , gotta see this thing through

 

[mb300sd]

Autopilots installed and she's driving! Traction is non-existent, especially with no weight in the car. Still waiting on my RTK module for cm-precision GPS, but I can drive around with the remote now.

Steering servo is plenty strong, I need to grind off the limit pins so I get a bit more steering range.

Ordered sonar sensors, so should have obstacle avoidance coming soon.

Next steps, 4G and camera, then I can try an autonomous drive down the park path.

 

[jlaeret]

Autopilots installed and she's driving! Traction is non-existent, especially with no weight in the car. Still waiting on my RTK module for cm-precision GPS, but I can drive around with the remote now.

Steering servo is plenty strong, I need to grind off the limit pins so I get a bit more steering range.

Ordered sonar sensors, so should have obstacle avoidance coming soon.

Next steps, 4G and camera, then I can try an autonomous drive down the park path.

View attachment 294491
View attachment 294490

Brilliant!

What is the circular thing you've mounted on the hood though? Some kind of antenna?

Good to hear that the servo works well, I might go down that route as well now that I know it works. Do you have a link to that servo?

 

[mb300sd]

Brilliant!

What is the circular thing you've mounted on the hood though? Some kind of antenna?

Good to hear that the servo works well, I might go down that route as well now that I know it works. Do you have a link to that servo?

There's a GPS antenna above it, its just an aluminum disc to serve as a ground plane.

https://smile.amazon.com/gp/product/B0027L7UDA/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

I ordered a second one to put in parallel for some extra punch once I get traction figured out.

I used these linkages and mounts,

https://smile.amazon.com/gp/product/B01ILCJQLW/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1
https://smile.amazon.com/gp/product/B0006O5I02/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

 

[Mobius484]

Looking forward to seeing this come together, will need videos!

 

[Tozz]

My daughter has been digging her new Radio Flyer model S, but as is typical for these types of toys, the plastic wheels have poor traction and the throttle is really just an on-off switch. There are many people that modify "power wheels" toy cars with rubber tires and variable throttles. I'm ready to try. Anyone want to help? I'm in Maryland, but think we can do this online. I have access to a small machine shop and a 3D printer.

I would really like better wheels! I have two of these things, and the noise they make on the street is horrible. My kids don't even hear me when I shout that they need to stop for traffic. There is not a lot I can do, I don't have any experience with this stuff so I'm merely an interested third party

 

[mb300sd]

Pics of steering.. should have taken some while I had it off, but you can get the idea.

This works decently for traction, but kept coming off. I painted the wheels with flex seal liquid, and then wrapped them before it fully cured, so we'll see how well it stays on now.
https://smile.amazon.com/gp/product/B00HWROV0E

 

[Hd172]

Is your project all done? I was thinking about making my daughters remote control because she is too short to reach the pedals right now. I probably shouldn’t have bought it yet but I got it at a super great price. How do you like your steering? I was seeing that people use linear actuators on the power wheel forums. A parts list would be great if you have one.

 

[mb300sd]

Steering works pretty good with the dual servos. I was going to use a linear actuator, but anything under $500 was too slow for the speeds I want it to run. Parts list was posted here, I pretty much stuck to that original plan.

 

[Hd172]

Steering works pretty good with the dual servos. I was going to use a linear actuator, but anything under $500 was too slow for the speeds I want it to run. Parts list was posted here, I pretty much stuck to that original plan.

Wait you’re just using the two HS-7954SH‘s? I have a 470oz servo on my rc 4x4. I may just buy another one and take it out of the truck. Thanks again

 

[Hd172]

Also what are you using for servo arms?

 

[mb300sd]

Yep, just the 2.

4PC 2" Hitec Servo Arm 1.5" 1.75" 5 hole 24T | eBay

 

[Hd172]

Well I finally got the time to finish my project. I ended up using a castle mamba x esc with a Futaba radio system I already had. I installed a single promodeler 470 servo. I ordered two but found this thing is so strong by itself using 6.0 volts. It can go up to 8.4v but I found I couldn’t overpower the servo by turning the wheel. I’m using a normal rc 2s battery for now until I figure out how much run time I’ll need. The original battery still powers the lights and horns. I did drill two holes to run the wires to the esc and rx in the trunk. I ran and zip tied the motor and servo wires along the existing wires. I also installed bullet connectors so I can go back to the stock setup anytime. It all looks stock when the the seat is on and the trunk is closed. Thanks for the help everyone.

 

[Nick_G]

I completed converted my RadioFlyer to remote control a few months ago using a large RC servo, I was unable to find a servo saver so I made my own using a couple of springs, the turning circle is not very good but it’s OK if you don’t mind doing 6 point turns. I’ve used a Spektrum DX4C RC control system and a Chinese brushed electronic motor speed controller (ESC). Keeping the RadioFlyer battery powered up is an issue as the BMS requires a coded data signal from the foot pedal but it does stay powered up for about 5 minutes. I’m currently investigating the possibility of upgrading the original brushed D.C. motors to three phase brushless motors but I’ve been unable to remove the helical cut motor pinions from the old motor or source any spare helical gear pinions. Has anyone else on here managed to upgrade the motor/gearbox assembly’s?

 

[ricebucket]

videos please!

 

[Nick_G]

videos please!

OK, If you must!

Dropbox - IMG_7850.MOV

 

[Melluh]

For anyone that is/has been workingbon this, how did you do the throttle control? I would like to keep using the switch that's already in there, if that's possible. Thanks!

 

[Melluh]

Update on my project: I tried breaking open the "gas pedal" and finding some way to control it, but no luck there.
The problem is that you can't just run the motors directly of the battery, as said before it needs to communicate with the pedal microcontroller to give sufficient current. Right now I'm trying to somehow hack the battery into giving out enough current anyway.

Summarized:
- Battery needs signal from gas pedal to give sufficient current for motors
- Thick green wire out of pedal connects to negative side of motors
- Thick white wire out of pedal connects to positive side of motors
- Thin red and white out of pedal are positive and negative of headlights
- Battery contains 16 cells, I think it's 4S4P

 

[kellymc]

Ah...this is probably my same problem, I've been trying to convert mine to RC control as well, but have been experiencing some motor controller issues, I bet it's because the battery is timing out w/o a signal from the gas pedal. I'm really interested in what solution you come up with

Update on my project: I tried breaking open the "gas pedal" and finding some way to control it, but no luck there.
The problem is that you can't just run the motors directly of the battery, as said before it needs to communicate with the pedal microcontroller to give sufficient current. Right now I'm trying to somehow hack the battery into giving out enough current anyway.

Summarized:
- Battery needs signal from gas pedal to give sufficient current for motors
- Thick green wire out of pedal connects to negative side of motors
- Thick white wire out of pedal connects to positive side of motors
- Thin red and white out of pedal are positive and negative of headlights
- Battery contains 16 cells, I think it's 4S4P