PROGRAMMING PNEUMATICS

[dpick1055]

It's actually fairly simple to have the trigger control an action with the pneumatics. What have you to do is declare some variable like handstate.

Then when your trigger is pressed changed the value of handstate to 1 or 0. Then when the trigger is pressed you know whether your hand is opened or closed and you can do an action based on it.

int handstate;
handstate = 0; //default position for whatever your using

if (p1_sw_trig == 1 && handstate == 0)
{
relay2_fwd = 1;
handstate = 1;
}
if (p1_sw_trig == 1 && handstate == 1)
{
relay2_rev = 1;
handstate = 0;
}

[Stvn]

Originally Posted by dpick1055

It's actually fairly simple to have the trigger control an action with the pneumatics. What have you to do is declare some variable like handstate.

Then when your trigger is pressed changed the value of handstate to 1 or 0. Then when the trigger is pressed you know whether your hand is opened or closed and you can do an action based on it.

int handstate;
handstate = 0; //default position for whatever your using

if (p1_sw_trig == 1 && handstate == 0)
{
relay2_fwd = 1;
handstate = 1;
}
if (p1_sw_trig == 1 && handstate == 1)
{
relay2_rev = 1;
handstate = 0;
}

Wouldn't that code just rapidly switch between forward and reverse relays? The handstate would immediately change to 1 when the trigger is pressed, so the next if statement will be true and the relay will be set to reverse. You need to check when the trigger is depressed. Something like:

int handstate;
handstate = 0; //default position for whatever your using

if (p1_sw_trig == 1 && handstate == 0)
{
relay2_fwd = 1;
handstate = 1;
}
if (p1_sw_trig == 0 && handstate == 1)
{
handstate = 2;
}
if (p1_sw_trig == 1 && handstate == 2)
{
relay2_fwd = 1;
handstate = 3;
}
if (p1_sw_trig == 0 && handstate == 3)
{
handstate = 0;
}

I think. Please correct me if I am wrong.

[dpick1055]

Oops. Sorry I think it should be

int handstate;
handstate = 0; //default position for whatever your using

if (p1_sw_trig == 1 && handstate == 0)
{
relay2_fwd = 1;
handstate = 1;
}
else if (p1_sw_trig == 1 && handstate == 1)
{
relay2_rev = 1;
handstate = 0;
}

Though I think your code would work too.

[gauntletguy]

the code will work, but you would need a timer or something, because if this code is evaluated more that once while the button is held down, the state would alternate very rapidly

[Neo3One3]

I had a similar issue when programming the pneumatics for our upper/lower claws, wrist, extension, and lateral drive. Let me show you how I solved the issue.

if (CLAW1IN == 1 && clawTimer < 3)
	{
		clawTimer++;
	}
	else if (CLAW1IN == 1 && clawTimer >= 3 && clawTest == 0)
	{
		CLAWFWD = !CLAWFWD;
		CLAWREV = !CLAWREV;
		clawTest = 1;
	}
	else if (CLAW1IN == 0 && clawTimer >= 3)
	{
		clawTimer = 0;
		clawTest = 0;
	}

In this case we use double action solenoids, so if you just use single ignore the CLAWREV. The clawTimer is used as a measure of necessary depression of the trigger to create a change (eliminating accidental presses) and clawTest is a signal to keep the values from changing again. However, you do need to make sure for doubles that you initialize them as 1, 0, or 0, 1 to begin with, or you'll get 0, 0, and 1, 1 values for the solenoid, I.E. nothing happening.

EDIT:
Oops, forgot to fill in for the definitions.

#define CLAW1IN p1_sw_aux1
#define CLAWFWD relay2_fwd
#define CLAWREV relay2_rev

[oddjob]

If you need an edge trigger rather than level trigger, do something like this - assuming that variable 'buttons' holds the state of the joystick(s) buttons, and 'old_buttons' keeps track of the previous state of the buttons:

  if(buttons!=old_buttons)
  {
    if((buttons&0x1)==0)      /* example - bit 0 is the button to react to */
    {
      do_something_here();    /* execute once per button push */
    }
  }
  old_buttons=buttons;

[Aarnat]

Hi,
I have seen teams with a board of switches that they have created themselves that controll things like pnunmatics. I would just like to know how we should wire the joystick port with the switches and then use them in the programming.

Thanks!

[Mark McLeod]

Wiring/programming for the joystick ports is detailed in
http://www.ifirobotics.com/docs/oi-ref-guide-5-8-07.pdf
starting on page 7.

[Aarnat]

Thanks!
So correct me if I'm wrong: a Single Pole Single Throw switch could have one end to pin 2, 7, 10, or 14 and its power to either 4 or 12. What if you wanted a Single Pole Double Throw switch to toggle up to exstend a piston and togle down to retract a piston?

[Mark McLeod]

Originally Posted by Aarnat

What if you wanted a Single Pole Double Throw switch to toggle up to extend a piston and toggle down to retract a piston?

You can toggle a piston with just an SPST since it has the two states you'd need, on/off (in/out for a piston).

But if you wanted to use a SPDT just pick a pair of pins from 2, 7, 10, or 14 and ground on 4 or 12.
Your code would decide what to do with that information.

[Aarnat]

Thank you to Mark and Leav,
I think we will use a SPST switch to save pins and the "off" position is to retract the piston and the "ON" position is to exstend it.

Thanks!!!

[Leav]

you could either use a couple of resistors to imitate the function of the analog "wheel" (circular thing on top of joystick), or use two seperate binary button inputs.

when using the "wheel" remember to account for slight variance in values.

-Leav