Should I build a 4 Wheel Steering Controller?

[heyok]

Help me out here.
Is there any need for this item?

This controller will operate your rear steering servo based on the position of a three position channel.

1. No Rear Steer. You just control the front servo as normal. The rear servo stays locked in the center.
   
2. Normal Rear Steer. Turning the steering control causes the rear servo to turn opposite of the front servo.
   
3. Crab Steer. Turning the steering causes the rear servo to turn in the same direction as the front servo.

This device would plug into CH1 and CH3 (or some other channel if you have a bunch) of your receiver. It will also have connections to the front and rear servos.

I think there may be others selling a similar product, but I will try and make the best one possible. Light, small, and waterproof, and at a reasonable price. I will stand behind it like I do all my stuff!

Please let me know what you think. If more than two or three guys think they would be in the market for one, I will consider offering them.

Thanks for your time.
Al

[JustinM]

I'd buy one!

[Charlie-III]

Sounds like a great idea. Especially if you do it to the same quality level of your other offerings.

As for me, I have no current plans for 4WS...sorry.

If I did go 4WS, I have a hacked GT3B.

If nothing else, free bump.

[SwampDawg]

awaiting for the product....

[The Violator]

I think punk made one at some point. Seemed interesting to me.

[jebster]

if the price is reasonable i might be interested. got a 6x6 i'm building with all axles being steered (2 up front, 1 rear axle) so being able to normal and crab steer would be nice.

[heyok]

Thanks for the replies.

Okay, I'll see what I can do.

[bowtie11]

I also would be in use of one if you make them i will buy one for sure starting my 6x6 tow truck!

[heyok]

I've made a lot of progress with this. The basic functionality is there - all three of the modes I mentioned are working. Now to do some of the finer points.

I would rather not, but I think it needs a couple of controls. Trim and End Point Adjustments. The Trim so that it will track straight and the End Point Adjustments so that the servo doesn't try and push the linkage beyond its mechanical limits and break things.

I wish I could do it without these things. Pots are susceptible to water damage, but they are really the nicest way to set these adjustments. Still, it might not be so bad. Once they are adjusted, some plastidip or silicone could be smeared over them to keep the water out.

The next decision is to use two or three pots. One as I said is for Trim.
The other two for the End Points, or , I can reduce that to one pot. That control would be used to limit the total swing. Does it make any difference to you guys weather there are two or three pots?

[m1009cucv]

i would buy one

[jebster]

Originally Posted by heyok

I've made a lot of progress with this. The basic functionality is there - all three of the modes I mentioned are working. Now to do some of the finer points.

I would rather not, but I think it needs a couple of controls. Trim and End Point Adjustments. The Trim so that it will track straight and the End Point Adjustments so that the servo doesn't try and push the linkage beyond its mechanical limits and break things.

I wish I could do it without these things. Pots are susceptible to water damage, but they are really the nicest way to set these adjustments. Still, it might not be so bad. Once they are adjusted, some plastidip or silicone could be smeared over them to keep the water out.

The next decision is to use two or three pots. One as I said is for Trim.
The other two for the End Points, or , I can reduce that to one pot. That control would be used to limit the total swing. Does it make any difference to you guys weather there are two or three pots?

i agree that pots add the most bang for the buck on capabilities. if you're already including 2 going to 3 isn't a problem. i personally would like to have separate epa settings.

[heyok]

Originally Posted by jebster

i agree that pots add the most bang for the buck on capabilities. if you're already including 2 going to 3 isn't a problem. i personally would like to have separate epa settings.

Thank you. I agree. Three it is.

[rmb2485]

If this requires a three position third channel, why not just skip the controller and plug the rear steer directly into the third channel? I think Punk's worked without a third channel and used a steering and throttle sequence to activate the rear steer.

[heyok]

Originally Posted by rmb2485

If this requires a three position third channel, why not just skip the controller and plug the rear steer directly into the third channel? I think Punk's worked without a third channel and used a steering and throttle sequence to activate the rear steer.

I used to run it directly from the third channel also. I guess the added benefit of proportional steering could be one reason.

The throttle sequence sounds clever and maybe annoying, but still an option if you didn't have a channel available.

[RootBreaker]

id be interested.. problem with the hacked 3b to me is that (my lack of understanding) is you have to go through the menu to do each set... id rather just run a Heli controller to get all the channels.. but id be interested in to see what you got and how..

[heyok]

Originally Posted by RootBreaker

id be interested.. problem with the hacked 3b to me is that (my lack of understanding) is you have to go through the menu to do each set... id rather just run a Heli controller to get all the channels.. but id be interested in to see what you got and how..

I hear you. Losikid knows that controller so well! I like the recipes he does up to get the control people ask for. Some stuff I can do, but if I leave it for a few days, I have to learn it all over again.

The GT3B/C can do a multi position channel. So instead of three positions, maybe have four or something.
Feed that into my steering controller and have another mode.

Maybe

1. Front Only
2. Rear Only
3. 4WS
4. CRAB

Start making too many options and it is hard to keep track of everything though.

I probably won't do much coding before the weekend, but should have something to show by Sunday if all goes well.

[losikid]

Originally Posted by heyok

I used to run it directly from the third channel also. I guess the added benefit of proportional steering could be one reason.

The throttle sequence sounds clever and maybe annoying, but still an option if you didn't have a channel available.

How are you going todo propo mixing and crab with a 3 position/linear channel? Right now the wantamix will do propo 4ws mixing, (front only, rear only, even mix, and all the inbetween bias) I thought about doing a dedicated 4ws firmware for the wantasummit platform, but i couldn't think of a good way to implement crab into the equation. I also talked to quite afew people and most "experienced" 4ws guys liked to have the rear steering independent, so i never pursued it much, especially since it was around the time of the gt3b coming out of the shawdows.

Originally Posted by RootBreaker

id be interested.. problem with the hacked 3b to me is that (my lack of understanding) is you have to go through the menu to do each set... id rather just run a Heli controller to get all the channels.. but id be interested in to see what you got and how..

What do you mean you have to "go through the menu to do each set"...

[heyok]

Originally Posted by losikid

How are you going todo propo mixing and crab with a 3 position/linear channel? ..snip..

The 3 position channel (or linear if that is what you have) selects the mode.

The regular steering signal then gets copied out to the rear servo or it gets inverted for crab steer or it just stays centered to lock the rear servo in the middle. To come up with a Trim, Left End Point and Right End Point, it will do a little math on the pulse widths.

[adamargue]

Id buy one. In the process of setting up rear steer on my rig now and it would be nice to have those options.

Sent from my SAMSUNG-SGH-I717 using Tapatalk 2

[RootBreaker]

Originally Posted by losikid

What do you mean you have to "go through the menu to do each set"...

well i was going to throw my own thread up when i had the cash together..

i would assume.. if im driving with front steer only... i would drive.. i get up a few rocks... then if i need to crab walk.. id have to go through the menu and choose it... then drive.. then menu to choose opposite steer... etc...
is that how the hacked one works?

that is why i was thinking of using a heli controller.. i can choose to do what i want when i want.... unless i am missing something with the hacked controller..

trust me i would love to support losikid... all for helpin forum members out.....

i figure heli controller... left stick fwd/rev on left... left/right front on right...
then take time to get used to rear left/right with left stick....