Hiding/showing walkways in edit mode (it is somethings not so easy to select items in edit mode)
More than one view in run mode (one or two small pop-up views so you have a better idea what is going on)
**New things in the palette
More electric switchboards (a large one standing on the ground and a small one just for 4 buttons)
Floor lines (so you can create zones for walking, operating, etc. just like in the real world)
Safety signs
Some extra smaller safeguards (width) would be nice
A table for an operator (so you can sort out a reject item for control by an operator. Afterwards he/she push a button on a small electric switchboard so he/she can insert the item)
The “old” paint mixing station would be nice
Improvements
Tank station : A door with a door switch on the tank
Tank station : A coil in the tank to heat the water (with temperature sensor)
Stacker crane : Light array sensor to the left & to the right so you can check if the load on a pallet is moved (to avoid damage)
Stacker crane : Digital limit sensors on the X & Y axis in Digital & analog configuration
Analog sensors & actuators : DINT range from 0 … 27648 (Siemens), DINT range from 0 … 32767 (common) : Add those two items to the configuration of these sensors & actuators
Those are some great ideas. I like the ancillary items such as a larger panel, walkways and tables that would make the simulation even more reflective of what we see in industry. A small 3 or 4 button PB Box would make a great addition for QC Stations where operators must gage parts every X number of parts.
New things in the palette:
White, blue and black buttons
4 bit rotary encoder (to select bases or parts)
Alphanumeric Display (4 lines / 20 characters) to use as user interface
I managed to program the Stacker without limit switches.
Even though they are a good idea there is x & z movement of the stacker so you know when it has stopped.
Our students also succeeded to program the Stacker crane without limit switches (as you described).
From educational point I would like to add limit switches. This for safety reasons, similar to a real Stacker crane, where the X & Y-axis is buildup with multiple safety levels (software event level, software alarm level, electrical limit switch level and mechanical stop level).
Geert, I am torn between wanting to see more limits and leaving the simulation a bit more challenging. I took advantage of the lack of position feedback to demonstrate to students alternate methods of programming. We did find that encouraging students to add limits of their own added some fun to the exercise and forced discussion in the classroom. If you are interested, I included some fully documented Siemens PLC Code on my website www.wayneschaefer.com where I show several examples of determining status. As I am sure you know, there are cases, on some machines, where we can not detect all positions and use alternate methods. Factoryio allows customization … it might not be “pretty” (see my labs 1 - 3, posted under shared projects) but it works. More safety components, however, would be a great addition.
I tried to do a small exercise for someone today and wanted to use the pick-place-robot. But one problem I encountered was, that the Z axis only had a sensor that told me it was not moving. With that the machine does not have a clear indication in what position it is.
I can’t tell my students “Ok, you have to take that signal, take the signal that you give to extend the arm, delay that by 100ms, and then check for a positive edge of the “not in motion” to decide if the arm is fully extended.”
Who would do it like that? You have a sensor that tells you if that thing is extended or not, so you can easily check if something broke and it has left is position, if it ever reached it final position and so on. At least in the real world. I don’t see why such workaround should be necessary. Same with the elevator that has no sensor to check if something if your load got misaligned and will crash the elevator.
Same with the stacker crane. There are no sensors on the stacker crane that check if the load is centered. Nor a sensor that checks if there is something already in the place where I am currently in front of.
Are there possible ways to work around this? Probably. At least for some things. Others not really. And it is also a question of education. It is always important to teach it “the right way” at least once. After that you can do experiments with less sensors.
But I guess the simulation wasn’t intended for those full fledged simulations where a student has to program a function that checks if the position where the stacker crane shall pick something up is valid. If there is something there. If the picking up was successful or not (meaning the load is now on the crane). So…I have some mixed feelings about this.
The idea of demonstrating an ideal situation is a good point and does allow a more streamlined approach with less confusion for the students. Some of the simulations allow additional proximity switches but the stacker crane is tough since the additional switches can not move with the crane.
