I'm building a picaxe-controlled macro rail system for my camera.
The linear guide & stepper (1.5amp per phase) is here
https://www.ebay.com/itm/322895892356
The controller board is here
https://www.sparkfun.com/products/12859
The Picaxe version TBD once I figure out what I need in the way of input/output, display, etc.
Here is my question (just learning about stepper motors): Is there a reliable way to avoid using limit switches at the ends of travel to stop the motor at the end of available travel? I have seen examples of switches/sensors used for this purpose but I have space problems and in any event would much prefer an elegant software solution whereby the motor seeks to a limit when first turned on and then retains that position in memory and indexes all other operations off that one identified limit and never touches a limit again until the next indexing operation. Total available travel is 50mm -- plenty for high magnification macro photography, but no extra space for sensors.
I have read in several places that it's hard to damage a stepper by hitting a hard stop to index as long as it's at low speed and low current, but there's a lot of misinformation out there and I don't trust the information without confirmation. Hoping someone here can give me some confirmation or otherwise. The system will be moving perhaps 2~3 pounds of camera -- not necessarily on a level plane -- and the motor is rated at 1.5 amps per phase, and the driver board is good up to 2.0 amps per phase without heatsink.
Thanks in advance.
The linear guide & stepper (1.5amp per phase) is here
https://www.ebay.com/itm/322895892356
The controller board is here
https://www.sparkfun.com/products/12859
The Picaxe version TBD once I figure out what I need in the way of input/output, display, etc.
Here is my question (just learning about stepper motors): Is there a reliable way to avoid using limit switches at the ends of travel to stop the motor at the end of available travel? I have seen examples of switches/sensors used for this purpose but I have space problems and in any event would much prefer an elegant software solution whereby the motor seeks to a limit when first turned on and then retains that position in memory and indexes all other operations off that one identified limit and never touches a limit again until the next indexing operation. Total available travel is 50mm -- plenty for high magnification macro photography, but no extra space for sensors.
I have read in several places that it's hard to damage a stepper by hitting a hard stop to index as long as it's at low speed and low current, but there's a lot of misinformation out there and I don't trust the information without confirmation. Hoping someone here can give me some confirmation or otherwise. The system will be moving perhaps 2~3 pounds of camera -- not necessarily on a level plane -- and the motor is rated at 1.5 amps per phase, and the driver board is good up to 2.0 amps per phase without heatsink.
Thanks in advance.