FANUC Increase Payload schedule-listing items

Hello,

Unfortunately I read somewhere that it is not possible to increase this limit...

I recommend taking your various payload sizes and creating 10 schedules that cover the entire range. Then just select the closest one. In most situations this is an adequate solution, especially considering that many people get payload wrong altogether and still function .

I wrote a small program to write to payload 1 and then set it dynamically. This might work for your situation. I haven't had the chance to test it though.

: !Payload in kg. ;
: $PLST_GRP1[1].$PAYLOAD=(AR[1]) ;
: !Payload CoG in cm. ;
: $PLST_GRP1[1].$PAYLOAD_X=(AR[2]) ;
: $PLST_GRP1[1].$PAYLOAD_Y=(AR[3]) ;
: $PLST_GRP1[1].$PAYLOAD_Z=(AR[4]) ;
: !Payload inertia in kgfcm^2. ;
: $PLST_GRP1[1].$PAYLOAD_IX=(AR[5]*980) ;
: $PLST_GRP1[1].$PAYLOAD_IY=(AR[6]*980) ;
: $PLST_GRP1[1].$PAYLOAD_IZ=(AR[7]*980) ;
: PAYLOAD[1] ;

That is what I am not sure of.

One way to test would be to put in a really heavy payload when you actually have a light payload and see if the arm overshoots its programmed points a little bit.

Another way would be to run a test path in auto, one time with a light payload set, and another with a heavy payload set and watch to see if the path cycle times change. Heavy payload should accelerate slower.

Quote from Nation

That is what I am not sure of.

One way to test would be to put in a really heavy payload when you actually have a light payload and see if the arm overshoots its programmed points a little bit.

And you could adjust the collision guard to be more sensitive, triggering a false collision.

You could also look at the disturbance torque status page (MENU > STATUS > AXIS > NEXT > F4 for "DISTURB".

The values in the allow column should change with the active payload.

I have never tested this personally so take this with a grain of salt: there is apparently a way to "trick" the controller to use the payload values for other motion groups as group 1, thus increasing the number of payload schedules available to group 1 beyond the default 10.

From what I understand, this process it long and tricky, and involved changing variables via a Controlled Start, rebooting, changing some other system variables, booting back into a Controlled Start, etc. I unfortunately have never used the process (and willingly admit I'm not 100% sure it even exists), but I would suggest reaching out to CRC to see if they can walk you through the process.

On an aside; will changing a payload's values programmattically on-the-fly via the above quoted $PLST_GRP1[1].$PAYLOAD=(n) system variable set mess with the motion planning algorithm that FANUC has running in the background to calculate motor torque, current draw, encoder counts/speed rates/whatever type of PID algorithm they have going on? I always assumed that changing the variable as it's being used could cause corruption of the motion planner.

I changed these variables over a year ago to 125 and the robot performed fine. The only limit is the memory it takes up in the controller.

From Operators Manual B-83284EN/10:

"Up to 10 of payload data can be set as standard. The number of payload data can be increased up to 256 by the following way. (up to 32 in R-30iB and R-30iB Mate)

a. Turn on the controller with [PREV] and [NEXT] key pressed.

b. Select "3 Controlled start".

c. Press the [MENU] key.

d. Select "4 Variables"

e. Set the number of payload data to the system variable $PLST_SCHNUM.

f. Restart (power off/on) the controller and "Control start" again.

g. Press the [FCTN] key.

h. Select "1 START (COLD)".

This worked for me on a R-30iB Mini Plus.