Class One Unlimited Buggy

[Leonardo da Bricki]

I finally got around to photographing one of my models, and figured I should finally post it. It has been raining for several days, and is forecast to do so for the next few days, so no videos yet. It was a model made to improve my skills from the last two I made, and it is definitely an improvement from before. Its fast, but if it isn't on a smooth surface it won't drive well (or at all) because it doesn't have enough torque.

Class One Unlimited Buggy:

Drive: 2 L-motors geared up 3:1

Steering: Servo motor

Suspension: full independent, front: double wishbone, rear: not sure, trailing arm?

Anyway, enough stats, I'll let the photos speak for themselves...

IMG_3198 by Valerie, on Flickr

IMG_3199 by Valerie, on Flickr

Soft, long travel suspension. A little too much so, it sometimes scrapes the ground when fully depressed.

IMG_3208 by Valerie, on Flickr

IMG_3206 by Valerie, on Flickr

The required underside shot.

IMG_3200 by Valerie, on Flickr

Finally, an experimental shot with dynamic lighting.

IMG_3204 by Valerie, on Flickr

C+C welcome! Thanks for looking!

 

[letsbuild]

WOW! That looks pretty fast. Is it? I really like the design too. Simplistic, and light, but very noticeable. May I reverse engineer that?

[Victor Imaginator]

Cool, i like design and how small it is. I think i will replicate this chassies for educational puprose. One question - hardcoupling L-motors with one DBG gear in the middle is neccessary?

[agrof]

Great MOC, I like it a lot.   I am interested in the performance, and in the construction of the rear swingarms, can You post some detail shots, please?

[timslegos]

Great looking buggy. It is hard to tell if there is enough space but a buggy motor for propulsion would make this fast!

[Leonardo da Bricki]

11 hours ago, letsbuild said:

WOW! That looks pretty fast. Is it? I really like the design too. Simplistic, and light, but very noticeable. May I reverse engineer that?

It is rather fast, more than my other builds. You may certainly reverse engineer it, I'll provide detailed photos later today if possible.

 

9 hours ago, Victor Imaginator said:

Cool, i like design and how small it is. I think i will replicate this chassies for educational puprose. One question - hardcoupling L-motors with one DBG gear in the middle is neccessary?

Thank you! Yes, it is necessary to hard-couple the L-motors to generate enough torque to drive the model at high speed.

 

2 hours ago, agrof said:

Great MOC, I like it a lot.   I am interested in the performance, and in the construction of the rear swingarms, can You post some detail shots, please?

You commented on this!!! That means a lot to me, I was inspired by your buggy! Yes, I will post more photos, and possibly a video later today.

 

1 hour ago, timslegos said:

Great looking buggy. It is hard to tell if there is enough space but a buggy motor for propulsion would make this fast!

There is more than enough space for buggy motors once the L-Motors are removed. If you mod my buggy, I would love to see the improved performance!

[nastystage]

Cool model!

I think you should remove the center 24t gear: the two motors will act as differential.

Edited October 16, 2016 by nastystage

[Leonardo da Bricki]

2 hours ago, nastystage said:

I think you should remove the center 24t gear: the two motors will act as differential.

The drive works, but at about half speed when it is taken out, so I left it in for greater speed.

[offroadcreations]

This is so awesome!

5 hours ago, Leonardo da Bricki said:

It is rather fast, more than my other builds. You may certainly reverse engineer it, I'll provide detailed photos later today if possible.

 

 

I hope you do; I'll reverse engineer it too.  I wonder if I can make it go faster with an Sbrick...

[letsbuild]

A Buwizz would probably make it go pretty fast.

I might try that.

[Leonardo da Bricki]

Sorry for the delay in posting the pics, I had some technical difficulties, which were coupled with misreading an assignment date, causing me to believe I had two days to write an entire paper...

@ Offroadcreat1ons & letsbuild: When (if) you make the mods, please post the results, I would love to see them!

On 10/16/2016 at 7:48 AM, agrof said:

 ... I am interested ... in the construction of the rear swingarms, can You post some detail shots, please?

Here are the requested photos (mini-instructions) of the swing-arms and a few more pics of the chassis with partial removal of the bodywork and one swing-arm removed. I have started to make some photo-sequence instructions of the chassis, but I don't know when they'll be ready.

IMG_3210 by Valerie

IMG_3211 by Valerie

IMG_3212 by Valerie

IMG_3213 by Valerie

IMG_3214 by Valerie

Here are some chassis pics for those who prefer to reverse-engineer.

IMG_3209 by Valerie

IMG_3217 by Valerie

IMG_3215 by Valerie

Thanks for looking!

[agrof]

Great Details, thanks for sharing!

The 6L link seems a bit stressed, but if not much - and it seems so, I personally can live with it.

[Leonardo da Bricki]

As far as I can tell, there is almost no stress whatsoever. Like you, I don't really care. Hopefully, I'll have the chassis instructions finished by Monday.

[Technyk32231]

On 10/16/2016 at 3:53 PM, Leonardo da Bricki said:

The drive works, but at about half speed when it is taken out, so I left it in for greater speed.

That makes no sense to me. Coupling the two motors together shouldn't affect overall output, since they are driving two independent shafts. You're still driving both shafts with two motors total, so each wheel should still get one l-motor worth of torque.

[Leonardo da Bricki]

Here is my best attempt at explaining that statement: One L-motor has X amount of torque. This is applied to shaft A. Shaft A provides a total speed of 1. The same occurs for shaft B. When they are coupled, the torque becomes X + X. This makes the speed 1 + 1, which equals a speed of 2. Thus, coupling the motors provides greater speed by strengthening the motor's ability to propel the buggy. Since the two L-motors are coupled, it basically has the effect of two motors driving one shaft. I hope that is clear enough, the real equations are pretty complex, but that is essentially what happens.

[letsbuild]

56 minutes ago, Leonardo da Bricki said:

Here is my best attempt at explaining that statement: One L-motor has X amount of torque. This is applied to shaft A. Shaft A provides a total speed of 1. The same occurs for shaft B. When they are coupled, the torque becomes X + X. This makes the speed 1 + 1, which equals a speed of 2. Thus, coupling the motors provides greater speed by strengthening the motor's ability to propel the buggy. Since the two L-motors are coupled, it basically has the effect of two motors driving one shaft. I hope that is clear enough, the real equations are pretty complex, but that is essentially what happens.

But, when it's like that, it becomes (X+X)/2, so it's actually better, in theory, to have the motors not hard coupled.

Edited October 23, 2016 by letsbuild

[Leonardo da Bricki]

Yeah, like I said, it was kinda hard to explain. Anyway, in practice, the coupled motors = better performance.

[Technyk32231]

Still makes no sense. As letsbuild said, the torque to each wheel becomes (x+x)/2. If you have the same overall input torque and same gear ratio, hard coupling the motors will not affect performance

[Leonardo da Bricki]

I tried to explain, but cannot do so satisfactorily. If you really must know the answer, create a separate topic, I can no longer help you. IF I have time, I might make a video to show the difference.

[Technyk32231]

I'm not saying I don't believe you, I'm saying that it does not make sense theoretically. The only way I can think of for that to work like that is if something is weird with one side of the drive.