Goody
Member
Dear all,
I would like to ask if anyone knows of a brand of PLC that has a RND or something like instruction.
RND meaning 'random' as in the BASIC instruction.
Something like move a value into a data register + RND where RND is given parameters such as between 6 & 50 so that a random number between (in this case) 6 and 50 is added to the original number. (or used on its own)
I ask this because I have been given a project where the customer wants a dying machine to randomly dye yarn passing under some dye heads.
(It is sort of a printing machine)
I wrote the original software for this machine and it has run great for a long while. But they tell me that sometimes they are having trouble with the knitting machines.
When knitted, the finished garment should have completely random colours in it.
Sometimes, because of the linear action of the dying machine, the colours in the finished garment are blocking together.
I have got around the problem with a sort of pseudo randomness. In that, the operator now inputs 6 random figures per dying head into the HMI
These are saved in 6 consecutive data registers per dying head. I then used index registers to alter the dye length each cycle.
It works and I could increase the amount of random numbers for a bigger random effect. But with 4 dye heads using 6 data registers each and more dye heads planned for the future I could run out of data registers.
The math(s) for the program is already using hell of a lot of data registers.
This problem is already solved and ok, but it is an example where a RND function could be used.
These special (ready made) functions are always used to save long lines of logic.
Does anyone know of a brand that has this function or does anyone think it would be a good idea to include this function in future models.
I would like to ask if anyone knows of a brand of PLC that has a RND or something like instruction.
RND meaning 'random' as in the BASIC instruction.
Something like move a value into a data register + RND where RND is given parameters such as between 6 & 50 so that a random number between (in this case) 6 and 50 is added to the original number. (or used on its own)
I ask this because I have been given a project where the customer wants a dying machine to randomly dye yarn passing under some dye heads.
(It is sort of a printing machine)
I wrote the original software for this machine and it has run great for a long while. But they tell me that sometimes they are having trouble with the knitting machines.
When knitted, the finished garment should have completely random colours in it.
Sometimes, because of the linear action of the dying machine, the colours in the finished garment are blocking together.
I have got around the problem with a sort of pseudo randomness. In that, the operator now inputs 6 random figures per dying head into the HMI
These are saved in 6 consecutive data registers per dying head. I then used index registers to alter the dye length each cycle.
It works and I could increase the amount of random numbers for a bigger random effect. But with 4 dye heads using 6 data registers each and more dye heads planned for the future I could run out of data registers.
The math(s) for the program is already using hell of a lot of data registers.
This problem is already solved and ok, but it is an example where a RND function could be used.
These special (ready made) functions are always used to save long lines of logic.
Does anyone know of a brand that has this function or does anyone think it would be a good idea to include this function in future models.