PierrePaulPaquet
Member
Hi,
I've been struggling to find information about this, even though it feels like it shouldn't be that hard.
I'm working on upgrading an hoist application. They were doing really basic position control for the hoist using a position laser. It basically was, when you get close to the target position, slow down, when you get to +/- (some value) from the target position, stop the drive and hope you stop at the position wanted. They didn't need huge precision, so it kind of works, but it is pretty ugly.
Now my question is this : using the same equipement, so a position laser giving the hoist position relative to the laser who is at the start of the hoist track and a SEW movitrac B drive (with the ethernet/ip extension, so i can use an ethernet module to communicate with it), how could i do position control that would be more fluid and precise then what they had.
We have a AB plc, so programming is done in Studio5000, but it is not a motion controller, so i don't think i can use the motion instructions as far as i know.
I was thinking of using a PID where my input would be my position laser and the output would be the speed of the drive, but my struggle with this is for the forward/reverse control. If the hoist actual position is lower then the target position, i go forward and my speed is positive, but if my actual position is higher, then my speed needs to be negative.
I know my post is pretty long, i'm not good at shortening things.
Thank you in advance, and don't hesitate to ask for more precision.
I've been struggling to find information about this, even though it feels like it shouldn't be that hard.
I'm working on upgrading an hoist application. They were doing really basic position control for the hoist using a position laser. It basically was, when you get close to the target position, slow down, when you get to +/- (some value) from the target position, stop the drive and hope you stop at the position wanted. They didn't need huge precision, so it kind of works, but it is pretty ugly.
Now my question is this : using the same equipement, so a position laser giving the hoist position relative to the laser who is at the start of the hoist track and a SEW movitrac B drive (with the ethernet/ip extension, so i can use an ethernet module to communicate with it), how could i do position control that would be more fluid and precise then what they had.
We have a AB plc, so programming is done in Studio5000, but it is not a motion controller, so i don't think i can use the motion instructions as far as i know.
I was thinking of using a PID where my input would be my position laser and the output would be the speed of the drive, but my struggle with this is for the forward/reverse control. If the hoist actual position is lower then the target position, i go forward and my speed is positive, but if my actual position is higher, then my speed needs to be negative.
I know my post is pretty long, i'm not good at shortening things.
Thank you in advance, and don't hesitate to ask for more precision.