Hey Guys ... ... Help me source a small electric motor It needs to be small, low speed, in fact very low speed (5 to 10 rpm at most) but I need the motor to be relatively HIGH torque. ... Also, it does not need to be a stepper motor as I intend to keep it simple by varying the motors supply voltage to control the RPM. Suggestions? ... Retail sources or DIY ... DIY as in rescued from some old tech? Thanks in advance [acronym=EYE See! To w00d's Photo Musings, my pages][shadow=grey,left][size=1em]w[/size][size=1.25em]00[/size][size=1em]d[/size][/shadow][/acronym] -------------------
What you building wOOd? How small? The little bit I've read would have one believe a dc motor does not like to run at very slow speed....?
wOOd - Check out the tiny gearmotors at pololu.com I think they have just what the doctor ordered. There are other places that sell these, but pololu is a real nice company to deal with. Wait... Did you say you were in Canada? If so, try solarbotics.com ...Tiger Note: The pic makes it look bit, but it's little.
Both of those guys have a lot of neat stuff, both mechanical and electronic. Both of them are long time dealers of mine so it wasn't hard to "find" them. Tiger
Bill, I was going to mention 'gears' although I thought I might have to build my own gearing system ... ... So thank you Tiger, ... the motor and gear shown would be perfect That will do the JOB nicely Here is what I'm planning, more or less
wOOd - Looked at your link. I still don't understand all the in's and out's of you using this thing, but my first impression is that I would build it a little different. First, if I was going to build it like the link, I'd think about putting two posts on that gear so that one was always engaged. Seems like it's just going to be a matter of time before the single post is going to hit the end of the sprocket and tear things up. If I was starting from scratch, I think I'd skip that approach and just use an MXL timing pulley. That would increase precision and give you zero slop. You could use a cam on the motor to switch the increments or better yet you could just use a timer on the motor to give you infinitely variable increments. You could also use dynamic braking to make the increments more precise. There are also a lot of other cool things you could do, but I'm sure you want to keep it simple. Just a thought! ...Tiger
For our serchers'n lurkers, the way the device works, with the post on the motor gear the motor rotates then rotates the tri-pod a fixed amount according to the size of the larger gear fixed around the tri-pod's horizontal movement. Theoretically more time there is between each movement of the tri-pod more time the camera has to do it's business or more time it has to take a single picture. The device is basically a mechanical way of making timed camera movements then triggering the shutter. Therefor automating the process of getting the necessary images needed for the 'stitching' software which will produce a finished panorama. Incorporating two posts to make the desired movements I can see making better mechanical sense but this would half (½) the time between each movement. This might work (all depend on the actual variables) and in all probability the two post idea will work. Regardless there is a possibility the camera might not have enough time to finish taking the image. NO way of knowing any of this until we have plugged in ALL the numbers or I have a working device we can 'tune' for the desired movement? "but I'm sure you want to keep it simple" ... True and I had thought about more elaborate methods to create the timed movements and a method of triggering the shutter. Such as what could be achieved by better mechanics, stepper motors and with electronic platforms such the Arduino or PIC device. In the end, though, those seemed as overkill with respects to the costs. But this is not to dismiss your ideas because they have been assimilated into my ideas as mine we're into the original poster's Nevertheless it's what it is, given the cost of the more professional systems which can cost up to near $500 it's beauty is in it's simplicity.
