DirectLOGIC PLC Motion Control S-curve Move Profile (Part 8 of 8) from AutomationDirect

In this last video of the Motion Control series, I will wrap up by demonstrating the various linear lead screw slide moves that can be made with the move profiles that were created. Follow me to see the results! I'll start by jogging the axis to the left and to the right by pressing the corresponding push button on the C-more Micro-Graphic panel. The pulse profile I programmed into the CTRIO module for jogging will execute as long as I am pressing either the Jog Left or the Jog Right push button as seen here. The pulse profile for jogging as described earlier in this video series was set up in the CTRIO module as a Dynamic Velocity profile type and assigned File Number 2. The various acceleration and deceleration rates for both Clockwise and Counter-clockwise were set to 10,000 pulses per second per second. I can program these values differently if later I feel I need a faster or slower response during a jog move. At this point let me demonstrate the over travel alarm conditions. Here I jog the slide to the right until the over travel right proximity is actuated. The stepper motor will stop and the C-more panel will sound its internal beeper. The C-more's panel background screen will flash between green and red, and there also will be a message displayed at the top left of the panel that reads 'Overtravel Right'. As mentioned in an earlier video, the alarm will continue until the problem is corrected. Here I jog the slide to the left so that the over travel right proximity is no longer actuated, which clears the alarm condition. The over travel left proximity operates in the same manner, but of course the message will alert me that the slide has over traveled to the left. Next I will Home the axis. I'll start by first jogging the slide axis to the left some distance so that it is away from the home position, and for sure not actuating the Home proximity sensor. Now I'll press the Home Axis push button on the C-more panel. The slide will travel to the right until it actuates the Home proximity sensor, it will immediately stop at this point, and after a split second, it will reverse directions, moving to the left, for a distance of 2,000 steps, which is one revolution of the stepper motor. As mentioned in an earlier video, this is equivalent to 'zero' 'point' 'one' 'two' 'five' [0.125] inches of travel. Homing uses the Home Search Profile Type that was created in the CTRIO workbench utility and was designated as File Number 1. Let me demonstrate the homing action one more time, but this time from the slide's point of view. The Trapezoid move profile was programmed to quickly accelerate the linear slide up to a predefined speed, and also quickly decelerate to a stop, over a total distance of 10 inches. I press the Trapezoid Profile push button on the C-more Micro-Graphic panel to actuate the move. The Trapezoid move profile was programmed in the CTRIO Workbench utility to move a total of 160,000 pulses. If you remember, each pulse to the stepper motor will move the slide a distance of 0.0000625 inches. Doing the math of 160,000 pulses times the distance that each step produces will move the slide a total of 10.00 inches. I programmed the Trapezoid to start out at a frequency of 40 Hertz, and also end at 40 Hertz. I use an acceleration and deceleration time of 1,000 milliseconds with a target top frequency of 20,000 Hertz. The profile edit box shows that my defined move profile should take 9.02 seconds to execute. A Trapezoid move profile is typically used to get from point A to point B in the quickest amount of time when some shock to the load is not a major concern. Here's the Trapezoid move again from the slide's point of view. I now have the slide axis homed again after demonstrating the Trapezoid move, so now I'll demonstrate the S-curve move. I press the S-curve Profile push button on the C-more Micro-Graphic panel to actuate the move. Like the Trapezoid move, the S-curve move uses 160,000 total pulses to produce a distance of 10.00 inches. I set the start and end frequencies to 20 Hertz. To show how the S-curve profile moves, I use 10,000 milliseconds, which is 10 seconds, for both the acceleration and deceleration times. I program the 'Pos Freq.' for a top speed of 25,000 Hertz. Notice that the profile never reaches the top speed. This is because the 'Total Time' of 16.27 seconds for the profile move is less than the combined acceleration and deceleration times. If desired, I can re-program the acceleration and deceleration times so that the profile will reach the top speed sooner. The S-curve move is primarily used for applications where any jarring motion from movement of the linear slide needs to be kept at a minimum, while understanding that the total amount of time for the move is increased. Here's the S-curve move again from the slide's point of view. To summarize the steps that it took for me to get my application operational, I start with the selection of the stepping system's components, determine the control method, create a wiring diagram, perform configuration of the hardware, program the CTRIO module using the CTRIO Workbench utility, program the DL05 PLC using DirectSOFT, and finally program the C-more Micro-Graphic panel. Well, that wraps it up for this series of videos on Motion Control. Keep an eye out for future videos on Motion Control on the LEARN Web site. In the works is a follow up to this video series in which I'll cover using the SureStep Stepping System with a CLICK PLC that communicates ASCII commands to an Advanced Stepper Motor Driver, and of course I will again use a C-more panel as my operator interface. Thank you for watching. Look for future videos at Learn.automationdirect.com, and also visit www.automationdirect.com for all of your automation and control needs.