Tutorial Arduino code for 4DOF and 1 DIRpin Hbridge board

I did figure out why there was so much force involved; I had the game manager settings at 100% rather than 20%

Mat, I have a question for you on your code.

Background to my question:

I connected my winch motors to the Arduino/Pololu755 rig. I am using standard 270degree pots which means that the winch lever will only rotate 5-10 degrees because of the gearing involved. The motor itself moves the full range but the gearing reduces this by the time the movement reaches the lever arm.

Question: Is there a way to increase the range sent to the motors in your arduino sketch? Something that would allow a 1/4 turn of the pot to equal a full rotation of the motor? Or some such?

Thanks

David

hello eaorobbie !

Yes, good idea ! ;D
There could be 3 paramaters to play on :
- the pwmMax (max speed limitation)
- the acceleration (in the PID part of the code)
- the range of movment (max angulation)

For each paramter, a pot could be wired to the Arduino in order to have live modification.

I can update the code this way :
- first, being able to modify easily the parameters in the code (like PwmMax) but it requires to re-upload the program after every change
- second, enable pots reading

Mat

hello David,

yes, I can do this :yes:

I'll insert a multiplier parameter (kind of gear ratio between motor and pot).
Give me some hours and check tonight !

I'll have to write the process for your tuning and translate this explanation :


Mat

Je ne parlez pas Francais, mais votre mind c'est beaucoup bel.

White board FTW. Very well explained.

@aarondc : thanks : your french is terrific ! champagne!

@historiker : i've updated the code in first post.

The process is the following : please, don't be too impatient ;D

1- upload the new code

2- calibrating the pot boundaries in the Arduino
const int potMiniRorL=300;
const int potMaxiRorL=700;
these values are convenient as they will always constrain the values whatever comes from the simulator software,
so the arduino will never send over-range value to the motors and your hardware will be protected !

Now without any game running ! send orders from Arduino serial monitor :

type the following strings in Hexa and press Enter:
R7FL7F
-> it should move the playseat in horizontal position

increase the angulation
R64L64
go farther cautiously
R3FL3F
if the playseat moves too little, then the potMini and PotMaxi are too close to middle position
and maybe go to max now : max backward tilt -> R01L01

- if it's too litlle check how much you can go further and decrease potMiniRorL, reupload and resend R01L01
and so on, until you found the pot minimal position

- do the same for potMaxiRorL, send RFFLFF and increase potMaxiRorL, reupload and resend RFFLFF

(write somewhere else these values that are associated to your particular playseat hardware).

3- find your pot amplifying ratio
- increase now the gearMotorRorLPotRatio (line 17)
- by default, it's equal to 1
- if you increase to 1,5 : the range will be increased by 50 %

no worries, if the amplifying ratio is too high :
- the playseat will not bump over the limits
- but the mouvments will be fast or jittering

Good tries !
Mat

Mat, I will give these a try! You, along with many others here, are a forum Superhero!

David

i will try this code tomorrow I'm just confuse with some things
..like were goes the pots wires and the h-bridge wires in arduino..the correct ports..the images doesn't show very clear
i read all the code but I'm not actually sure.. can some one help

The potentiometer wiper wires to to the Arduino ports A4 and A5 (if you are only using two motors).

The positive and negative potentiometer wires go to their respective ports on the Arduino.

Dir (motor 1) is Pin 2 on the Arduino, Dir (motor 2) is Pin 3 on the Arduino.
PWM (motor 1) is Pin 6 on the Arduino, PWM (motor 2) is Pin 9 on the Arduino.

thanks I've made an small draw to facility so it goes like this

now another question... it needs xsim software to work? i think so but just asking..
and thats all just need to upload the code?..

(Pssttt.....no X-Sim here....only SimTools)

Hi Trust928!

Nice to see your interest!

Here is a wiring diagram http://gamoovernet.pixhotel.fr/pics_gamoovernet690px/20120703223559-lipide512-wiringdiagram.gif

You can make your motors moving without any simulator software and without game:
this is the first step I advise you to follow for your safety and hardware!
start Arduino Serial Monitor and write manually orders to make the motors move...

The Simulator software you need is Simtools developped by yobuddy and plugins developped by Value1
As Simtools is not released yet, you have to ask for beta testing to RaceRay. Then you'll be granted to Simtools download page.

thanks racing mat I've asked them for the softwares and plugins now must wait them reply..

Wooww! Your project is cool . I'll ask you about support your project in my software

Congratulations!

@korrea: Thanks for your compliments!
You're welcome

Some news: I've retested the chinese HBridge for a longer run...
H..y shit! After few minutes (without load) one Hbridge started to smoke and kill my Arduino
just like Historiker... and the Ard cannot be updated anymore : avrdude error 500

This chineese Hbridges are too cheap! and finally cost more...

PREFER POLOLU!

PS : I can't update the first post: there are more than 13000 words...

HA! I am not crazy or irresponsible!!! Er.....ok perhaps I am (according to my wife) but not in this case, lol

I am actually sorry to hear that it is the H-bridge. I had hoped that they were actually good and I could use another one in my future builds.

I all time say, that I strongly recommend to use galvanic isolation...