Hallo zusammen! (english version below)
Ich arbeite derzeit an einem Projekt, bei dem ich ein Unterwasser-Linearschienensystem baue. Ich habe bereits das Schienensystem und brauche nun noch Motor, Treiber und Mikrocontroller. Das Linearsystem soll auf verschiedene Abstände eingestellt werden können (5cm, 10cm, 15cm usw.), weshalb ich mich für einen NEMA 17 Motor entscheiden würde, da er mir erlaubt die Schritte zu zählen.
Habt ihr Vorschläge für eine gute und zuverlässige Kombination aus Motor, Treiber und Controller? Ich bin offen für alle Vorschläge.
english version:
Hello everyone,
I am currently working on a project where I am building an underwater linear rail system. I already have the linear stage and now need to choose a motor, driver, and microcontroller.
The system should be able to move to specific positions (5 cm, 10 cm, 15 cm, etc.), which is why I am considering using a NEMA 17 stepper motor, as it allows me to control position by counting steps.
Do you have any recommendations for a good and reliable combination of motor, driver, and controller? I am open to any suggestions.
Any controller would handle it.
Estimate the torque and speed desired. From that select the stepper. NEMA17 is a useless description in this respect.
When You know the torque You will know the current. From that You can select the driver.
Select voltage according to acceleration. Higher acceleration usually calls for higher voltage and software capable to acceleration. The voltage must also be considered when selecting the driver.
The TB6600 stepper controller is a good piece of kit in my experience. Wide range of input voltages, capable of very small micro steps and precise control.
I’ve been using one with an Arduino board controlling a self-balancing robot. For NEMA 17 sized motors I’ve only needed the second lowest (of 8) current settings. If anything the controller is almost too powerful and I have to limit the run time to prevent overheating.
I use an Arduino MKR series microcontroller, but you could use anything, it’s just a simple 3 digital outputs, enable, direction and pulse. For the pulse train you need to generate a fixed duty but variable frequency corresponding to the speed you want it to move.
I can’t guarantee it will work underwater though. 
These work well Amazon.com : Stepper Motor Driver TB6600 4A 9-42V Nema 17 Stepper Motor Driver CNC Controller Single Axes Phase Hybrid for CNC/42 57 86 Stepper Motor (TB6600-1pcs) : Tools & Home Improvement and if you look around, you can find them with motor included.
For a complete control system search Amazon for the MKS DLC32 controller. It’s very popular on laser cutters and will control 3 NEMA17 size steppers.
NEMA17 only tells about the size of the mounting plate. It tells nothing about the electrical characteristic. And counting steps is possible with every stepper. The main thing you need to know is the required torque (and speed - torque is lower at high speeds ). The already mentioned TB660 is is relatively powerful and good value for money. But of course there are other drivers as well.
To control the stepper you could use my MobaTools library. It supports acceleration/deceleration and you can position the stepper very easily. You don't have to care about counting the steps - this is done by the lib.
P.S. Für die MobaTools gibt es auch eine Beschreibung auf deutch 
NEMA 17 motors don’t usually exceed about 2A. The TB6600 can deliver 4A peak so you could likely run two motors in parallel, or possibly even more depending on what motor variant you choose and the torque you need.
