- #1
sgc7of7
- 12
- 0
Hi everyone.
I'm in the process of designing a telescope mount, and am now trying to figure out how to drive the thing. Ideally I would like to go with an off the shelf dc motor and gearhead setup, as this appears to be the cheapest option. My problem is, that I don't know how slowly you can run a dc motor before you start to cause issues - like cogging, or maybe burn-out, or who knows what. So I was hoping that you guys could give me some pointers...
Here's some specs that I think are required:
-The system must turn at around 1 revolution per day.
-Start-up torque, with safety factor included, is about 20Ncm.
-Normal running torque will be significantly less than above.
-Budget is around AU$200 per axis (this is the main problem!)
Stepper motors are not an option, unless someone can help me prove that the cogging of a micro-stepped stepper is comparable or less than that of a standard dc motor.
Becuase I've come in on this project three quarters of the way through, I'm a bit limited by the design so far - so a great big worm gear arrangement probably will be a little too tricky to implement (and would play havoc with the budget too I think).
I guess what I would primarily like to know (at this stage ) is how to figure out how slow a dc motor can safely go given the data provided by manufacturers such as mclennan.co.uk and pittmannet.com.
I'm sure there are a million other questions too, but I just don't know them yet! I've trawled the net and various textbooks too, so if anyone can suggest some good texts etc, that would be great.
I'm in the process of designing a telescope mount, and am now trying to figure out how to drive the thing. Ideally I would like to go with an off the shelf dc motor and gearhead setup, as this appears to be the cheapest option. My problem is, that I don't know how slowly you can run a dc motor before you start to cause issues - like cogging, or maybe burn-out, or who knows what. So I was hoping that you guys could give me some pointers...
Here's some specs that I think are required:
-The system must turn at around 1 revolution per day.
-Start-up torque, with safety factor included, is about 20Ncm.
-Normal running torque will be significantly less than above.
-Budget is around AU$200 per axis (this is the main problem!)
Stepper motors are not an option, unless someone can help me prove that the cogging of a micro-stepped stepper is comparable or less than that of a standard dc motor.
Becuase I've come in on this project three quarters of the way through, I'm a bit limited by the design so far - so a great big worm gear arrangement probably will be a little too tricky to implement (and would play havoc with the budget too I think).
I guess what I would primarily like to know (at this stage ) is how to figure out how slow a dc motor can safely go given the data provided by manufacturers such as mclennan.co.uk and pittmannet.com.
I'm sure there are a million other questions too, but I just don't know them yet! I've trawled the net and various textbooks too, so if anyone can suggest some good texts etc, that would be great.