Uploaded July 2025 | Updated September 2026, 1 week ago
"One accurate measurement is worth a thousand expert opinions." — Rear Admiral Grace Hopper, U.S. Navy
TEST RESULTS:
3σ repeatability of ±0.01 mm, better than a single microstep, despite the slight mechanical flex of the 3D-printed setup.
Note: In most stepper motor applications, repeatability directly reflects homing accuracy, making sensorless homing a compelling option.
ABOUT SENSORLESS HOMING:
Sensorless homing is a technique for stepper motors that detects contact with a hard stop by sensing motor stall, eliminating the need for external limit switches!
Unfortunately, there is little documentation available on the precision and repeatability of sensorless homing...
TEST SETUP:
- A 0.01 mm dial gauge was used, positioned 25 mm from the stepper shaft to precisely measure the homing position.
- NEMA 17 stepper motor (200 steps/rev).
- The hard-stop (home) is detected sensorlessly with the stepper rotating clockwise (CW).
- From the home position, the stepper rotates a fixed number of steps counterclockwise (CCW).
- The dial gauge reflects the repeatability of both the sensorless homing and the fixed step movement from home.
- Stepper speed of 1200Hz (0.75 revs/sec).
- The test was repeated 50 times at both 1/8 and 1/64 microstepping; The video covers the test at 1/8 microsteps.
RESOURCES:
🔹 Code & Examples for Sensorless Homing:
github.com/AndreaFavero71/stepper_sensorless_homing
🔹 Sensorless Homing Demo (3D print and board by Lewis - DIY Machines):
youtu.be/fMuNHKNTSt8
🔹 Lewis’ (detailed) video tutorial:
youtu.be/TEkM0uLlkHU
"One accurate measurement is worth a thousand expert opinions." — Rear Admiral Grace Hopper, U.S. Navy
TEST RESULTS:
3σ repeatability of ±0.01 mm, better than a single microstep, despite the slight mechanical flex of the 3D-printed setup.
Note: In most stepper motor applications, repeatability directly reflects homing accuracy, making sensorless homing a compelling option.
ABOUT SENSORLESS HOMING:
Sensorless homing is a technique for stepper motors that detects contact with a hard stop by sensing motor stall, eliminating the need for external limit switches!
Unfortunately, there is little documentation available on the precision and repeatability of sensorless homing...
TEST SETUP:
- A 0.01 mm dial gauge was used, positioned 25 mm from the stepper shaft to precisely measure the homing position.
- NEMA 17 stepper motor (200 steps/rev).
- The hard-stop (home) is detected sensorlessly with the stepper rotating clockwise (CW).
- From the home position, the stepper rotates a fixed number of steps counterclockwise (CCW).
- The dial gauge reflects the repeatability of both the sensorless homing and the fixed step movement from home.
- Stepper speed of 1200Hz (0.75 revs/sec).
- The test was repeated 50 times at both 1/8 and 1/64 microstepping; The video covers the test at 1/8 microsteps.
RESOURCES:
🔹 Code & Examples for Sensorless Homing:
github.com/AndreaFavero71/stepper_sensorless_homing
🔹 Sensorless Homing Demo (3D print and board by Lewis - DIY Machines):
youtu.be/fMuNHKNTSt8
🔹 Lewis’ (detailed) video tutorial:
youtu.be/TEkM0uLlkHU
