K8055 + Sabertooth + Wiper motors

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi Bigtalltim,
Thanks for the compliments. You have just made an excellent analyse, and a very good summary of what I wanted to explain (but my english is not so good).
I hope we are right with this kind of frame construction.
Of course, I will test very soon. And I will certainly post a video of the result. But I need few days to finalise everything.
Thanks again for your explanations and your analyse.
See you

----------------------

Just one more thing : I put the same picture on a french forum, and it seems that other guys have already tested this kind of frame, with slide potentiometer. They speak about parasit or interference betwwen the 2 wiper motors, and then on the 2 potentiometers. I think I understand what they mean.
But I want and I need to test in order to realise what they are speaking about.

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi all,
This solution doesn't seem to work properly. In fact, I can move the frame with the sliders of the test-plugin of force sender, but only separatly. If I try to move the 2 axis in the same time, the frame moves continnuously and doesn't stop at the consign.
I can't really understand why, but other guys have already told me it would not be possible with this kind of solution (potentiometers linked to the frame), and they were right.


So, I imagine the potentiometers should be linked directly to the motor, and not to the frame.




Regards

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

LASTEST TEST with a nice result !!!



http://www.youtube.com/watch?v=NHiaFQfZNmE

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi Adbgg

don't be put off by a single test failure (or what other people tell you!)

There should not be too much of a performance difference between attached to the motor or attached to the frame...
AS LONG AS... the range of movement uses the full sweep of the sensor

I suspect that the setup you have tested (which reduces the range of movement so that the pot is not damaged at the extremes of position) has reduced the movement too far...

If this is the case, the result would be that the wiper motors will continue to spin even when the frame reaches what you had expected to be the extreme of position

I am guessing that this problem is because the reduced movement of the frame means that the pot never gets to 100%...
The motor is trying to push until the pot reads 100%, which it never will, so the motor never stops - it will keep trying to push!

The fix should be simple - just move the arms with the connection to the pot closer to the arms on the wiper motors.
This would increase the movement experienced by the pots, and may help you to find your expected position

I don't think this is a failure of concept - rather, a failure of configuration/callibration

Tim

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi BigTalltim,
Very strong analysis you made, as usual.
In fact, I've tried with maximum amplitude of the potentiometers (by hand, deconnected of the frame), and I've also tried with a smaller amplitude of the pots, connected to the frame. But the difficulty is that when only one motor moves, the 2 pots move. And because I didn't succeed to configure everything to make the frame work as expected, I decided to change and to connect the pots directly to the motors. Very much easier to configure.
Maybe, you are right, and if you succeed to make it work with the pots connected to the frame, I would be very interested.
I fear that I don't have enough courage anymore to continue my tests at the moment. I've reached my first aim, I mean to build a frame with K8055 + Sabertooth + Wiper working with X-SIM.
I will certainly continue later, in few weeks...
Many many thanks BigTallTim. You are a kind of spiritual father for me through this forum....(smile).
Your analysis are always very impressive. Big THANKS for this.
Regards
Adbgg

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Tim you are correct!

abdgg: your concept is doable with careful adjustments, but in the end it is not worth it. As you realized moving one motor will affect the other, and thats where problems begin. The pot's and range of movement also has to be carefully adjusted otherwise the motor will run away because it has to go somewhere the potentiometers cannot.

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi adbgg

I really like your project and I am going to use all this information on mine.

I seems you never considered using the 5V output of the Sabertooth to power the potar, why ?

Merci
Fern

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Et bien tout simplement parce que je n'y ai jamais pensé. La question est pertinente, c'est certainement une excellente solution pour alimenter les potars.
Maintenant, l'alimentation de PC fournit du 12V et du 5V assez facilement...alors je n'ai pas cherché plus loin, à tort.

Very strong question !!!
I never think about it.
It is certainly a good solution to supply the potentiometer. Thanks for this good idea.
The PSU is able to supply easily 12V and 5V, so I have never imagine to use the 5V Sabertooth output.

Just a remark : check all the voltages. Because 5V is not always 5V.
For example, I decided to supply the K8055 with the PSU and not the USB cable, which was not exactly 5V.
And, if you want to use the full range of your potar, you need to supply a good 5V (BUT NOT MORE, otherwise you will have strange feedback : It was already very well explained by Bigtalltim if I remember).

Regards

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

good experiment bro

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Je me demande si le 2X10 ou 2X12 compare le signal reçu qui doit se trouver entre 0 et 5V avec le 5V qu'il propose lui-même dans un tel cas on obtiendrait toujours le maximum du rendement puisqu'il devient lui-même la source n'est-ce pas ?

I am wondering if the 2X10 or 2X12 compares the signal it receives which should be between 0 and 5V with the output it proposes in such case we would always have the best performance since the voltage range would come from itself, isn't it ?

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Bonsoir,
Si je comprends bien ta question, je répondrais : non, je crois que le 5V qui permet d'auto-alimenter les potentiomètres depuis la Sabertooth reste constant (toujours 5V), alors que le signal varie grâce aux potentiomètres en retour, ce qui fait que les moteurs tournent vite ou lentement, dans un sens ou dans un autre.

J'avais déjà effectué un test pour comprendre le fonctionnement de la Sabertooth couplée directement à des moteurs, et sans K8055.
A+

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi all,

With the agreement of stephane61d and Chris2, french guys who succeeded to build their own frame based on K8055 + Sabertooth, I post their videos...awesome !!!


STEPHANED61

http://www.youtube.com/watch?v=cbcp-NglFog&feature=youtube_gdata



CHRIS2

http://www.youtube.com/watch?v=FuD8VMmxwvs

http://www.youtube.com/watch?v=xwwGkzv3mDE


A BIG THANK TO THEM

Regards

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

The last one (KAMI84).
An other frenchy !!! Nice.


http://www.youtube.com/watch?v=IdvOmWyteGs

Re: Small Prototype / VM110 + Sabertooth 2 x 10A

Hi all,

One more frenchy guy with a new concept (K8055 + Sabertooth + drill motor)


NIKO77

http://www.youtube.com/watch?v=F5v_CaZyG0o

Regards

F=m*a

Those french constructions would perform better, if the levers would connect in shoulder area, rather than on the bottom, near the joint. There is not enough leverage imho. Thats probably why the seats move so slowly.

The drill motor setup doesnt seem to be an improvement comparing to the wiper motors.

I'd like to see that Sabertooth+wiper motor combo perform in a normal setup, with motors on the bottom, and levers connected to the seat in shoulder area.

Regards

I don't Agree with you! I don't think my motion simulator is slow.
My calculations are good and it works fine.

Hi egoexpress,

Concerning NIKO77 and his frame based on Drill-Motors, I thought it was a good idea to post his video, because it is really new and original. I've never seen this kind of solution before. Furtheremore, NIKO has developped his project with a Sabertooth board, so it is also normal to speak about him in this post.
To be hosnest, I'm really surprised by NIKO77, CHRIS2, STEPHANE61, KAMI84, because they've realised their projects very quickly...in a couple of weeks, meanwhile I'm still thinking about my own frame and how I will build it. It is funny. I spent a lot of time to explain how to do on X-SIM and Racingfr forums, and I've not built anything yet, excepted 2 or 3 little prototypes.

The most important concerning NIKO and his Drill-motors, is that it works. You are right when you say it seems not to be an improvement compared to wiper motors, but it is an other possible solution. I will post your remark on the Racingfr forum concerning the position of the joint and the levers (near shoulder area). I'm sure they will be glad to know that I have a message for them from egoexpress.

But I have also a question for you : I know that there is still a little problem with the Sabertooth, because this boards needs a 2,5V signal to stop the motors. And when we start X-SIM, the signal is 0V. Consequently, the 2 motors move quickly (as yo know 0V means full speed), whereas we want them not to move.
Maybe you have a solution. I heard something about plugin modification but I don't know exactly what to do. Your advice would be really appeciated, the frenchy community would be grateful for a solution.
Regards
Adbgg

PS : An other question concerning dynamic option. Do you have any suggestion concerning this option and how it could work with the K8055+Sabertooth ? I didn't take the time to continue the tests with this option until I discovered the 2 speeds in analog interger mode. But I know that other people would like to make this option works with K8055 + Sabertooth. Any proposal would be appreciated.

I think they all look great and work well. Here are different variations of sims we can all aspire to!
All your jobs are fantastic! Love all your work! :

Although the leverage is considered, but there are other points!
For example what is the mass of the simulator?
what is the motor torque?
What is the distance between the pivot and rods?
example , for 2 simulator:
if our simulator X is 10kg lighter than yours,
setting up of the shoulder has no interest.


if the motor torque and the lever arm is sufficient to raise the driver with the nominal values of the engine, there is no problem using this configuration with the engine under the seat

adbgg thought about using tronics h bridge instead of sabertooth, has potential.