one of these multi axis accelerometer/inclinometer/etc boards.
If we mount something like that on the sled parallel/perpendicular to a known
object (like the vertical leg of the vertical pantograph, 90deg ring mount, or
along the 45 deg of the wood pantograph) wouldn’t it tell us at when it’s
level to the bottom of the frame/floor?
with the triangulation kits (arms or ring), we don’t care if the sled is level
or not, it doesn’t matter.
spitballin’ a calibration example:
3D print a sprocket cap on which to mount the sensor, cap slips over the sprocket with a tooth at vertical.
3D print a mount for the sprocket cap that is attached to the sled in the manner described above.
Mount the sensor to the sprocket and auto-level to 12 O’clock sprocket with sensor and software.
if you are looking for sub-degree accuracy, you are going to need to calibrate
your 3d printed part and how the sensor attaches to it.
repeat for both chains.
Remove sprocket cap and place on sled mount, on sled.
Place chains on 12 o’clock sprocket like the current calibration and feed out both chains equally to ‘center or below’ based on user input.
enough chain is fed to attach the sled, attach chains to the sled.
sled mounted sensors are in a known configuration.
auto level the sled based on sensor with software.
I don’t see that the angle info of the sled helps you.
bonus: grok and store frame angle.
bonus: calculate sled pressure on work surface based on sled weight/frame angle, store for later when we determine idealized sled weight/placement.
without knowing friction coeficcients and surface area, that doesn’t help.
feed equal amounts of chain to move sled to bottom of workpiece manually so bit touches outside bottom of workpiece.
other than finding the limits (which I have suggested that we do), how does this
help? and how does the sensor help us?
repeat with top of workpiece.
isnt that all we need? (in addition to existing ‘vertical height of sprockets above workpiece’ and ‘linkage measurements’)
no, this has given us no information on the rotation radius or chain sag that
the current calibration figures out.
I have advocated that we should not do the Y offset measurement, but instead
have the user move the sled to the home position (in one link steps so we can do
the ‘marked link’ reset directly to the home position), and then after the
calibration, move the bit ‘around the world’ to define the software limits
(don’t move the sled outside of this area without popping up a warning)
But that didn’t end up being the option selected.