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Well done, I was trying to pick the bits used. (Random bits ?)
Would love to hear what bits you used, and how you interfaced it.
I thought I saw some Festo bits, but the video was a bit fuzzy.
t is the End result that matters, not the Tools used to get there.
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Mine's a pre-designed magazine job.
Screwing with your reality since 1998.
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Dinosaur:
The major components were:
-Modicon PLC
-Inductive Limit Switches
-Physical limit switches
-Rodless Cylinder
-Fork Lift Mechanism with 120VAC synchronous motor for control.
-Rotary table (The only challenge there was controlling it) With 5V stepper motor for control
-12VDC motor
-Piston table
-Gripper hand
-Foam block
Other than that, I had electro-mechanical relays, AC SSRs, power transistors, a microstep stepper motor drive (Which worked terribly), and a bunch of other random objects that ended up being important. I also had some pneumatic relays I had to do terrible things to to get enough solenoid valves running to actually power all the different pneumatics. Those were just for the drives(you might consider it a controller) for everything though.
Oh yes, and wood. Lots and lots of wood.
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I was given a LEGO RCX set, and made stuff with that over and over and over again. I even made a robot that played catch with me.
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That was quite a list.
Actually "low speed" stepper motor control is really very simple.
Particularly with a plc, as its scan time is usually very stable.
My first stepper was controlled by 4 DC opto22 ssr's switched by a qb program.
Once you know the step sequence (for full step or half step)
it is just a case of switching the outputs ON in the right sequence.
Just use timers to start slow and accelerate and decellerate.
Tricky bit is to do that , so that the weight of the table doesnt stuff it up.
In any case, you did well.
t is the End result that matters, not the Tools used to get there.
Posts: 729
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Joined: Jan 2003
The half step controller was a breeze to create, but it gave less than one degree of precision. The microstep controller suffered its own problems though -- namely, sucking.
Controlling that DC motor was a far greater problem, because at the time I wanted variable speed control using PWM, but I didn't have any semiconductor devices capable of passing the appropriate current. Instead, I ended up using a pair of electro-mechanical reed relays with a few different sets of contacts to make an H-Bridge. I still needed a massive resistor to keep the current from burning out the supply, but everything worked, at least.