From d365bf11cac6c9f032b5d1cd709e4790d41b6a73 Mon Sep 17 00:00:00 2001 From: Nico Stute Date: Mon, 13 Aug 2018 20:31:23 +0200 Subject: [PATCH] Update Getting Started.adoc --- docs/src/Getting Started.adoc | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/docs/src/Getting Started.adoc b/docs/src/Getting Started.adoc index d0d5dfb8..4ab28d28 100644 --- a/docs/src/Getting Started.adoc +++ b/docs/src/Getting Started.adoc @@ -549,7 +549,7 @@ If you can't measure this set it to 0.001/(phase resistance). 1. attach a power supply to the motor (limit the current) 2. turn the motor one rotation and count the number N of positions it snaps in conf0.polecount = N -### torque constant conf0.psi (Nm/A) ### +### torque constant conf0.psi (V*s/rad) ### The default value works for most motors. Normaly you don't have to measure this! There is no common ground for the toque constant. Some manufacturers state the current in RMS, others in peak-to-peak. We also stumbled over values that were neither. @@ -565,15 +565,16 @@ How to determine psi: It's also possible to measure psi directly with STMBL. Maybe even automatically in a future version. 1. Disconnect the HV power, leave the servo connected. -2. Connect with Servoterm, drag&drop this file into Servoterm: https://github.com/rene-dev/stmbl/blob/newstuff/conf/psi.txt +2. Connect with Servoterm, drag&drop this file into Servoterm: https://github.com/rene-dev/stmbl/blob/master/conf/template/psi.txt 3. Type `stop` and `start` 4. Turn the shaft of the motor. You can use your hand for a rough estimation, but it's probably better to drive with a cordless drill. The closer to the nominal RPM rating, the more accurate the result will be. There is no need to turn the shaft continuously, a quick short turn of one revolution is sufficient. 5. Type `psi0.max_psi` and you will get the peak psi value that was measured. You can set `conf0.psi` to the measured peak psi value now. If you did not drive the motor reasonably fast, the proper psi value is probably a couple percent higher. - #### KV #### psi = 60.0 / #POLE_PAIRS / sqrt(3) / 2.0 / PI / KV +#### Nm/A #### +psi = (Nm/A) / 2.0 * 3.0 / #POLE_PAIRS #### PID #### The default values work for most motors. Normaly you don't have to tune this.