Topics

Help - Astro Physics 1200 - RA Tracking Issue


Rockmover
 

I finally got around to testing the AP1200 mount and OnStep step. 

However, I have an issue which I "believe" is the RA motor is missing steps when it is just normally tracking.  Below are the PHD2 graphs.  I can slew all over the sky as much as I like and the mount works fine.  Targets are all pretty close, and when I go back to the original spot I am pretty much dead on.  So for that reason I "don't" think I am missing steps otherwise I would think slewing would also be off?  But I am not sure?

My polar alignment is spot on. I am using drift alignment for 10+ minutes, and the AP is on a concrete pier, so nothing is moving.  I also checked polar alignment using a Polemaster, and again it was spot on.

BUT, if I try guiding the RA axis is always forcing steps to keep up (image below).  In fact if I got for 10 minutes the RA corrections will be a set of solid blue correction bars all in the vertical direction.  Furthermore, if I go into guiding assistant in PHD2, the second guiding is turned off, the RA drops like a rock (again image below second red arrow).  This is not PE error as it doesn't come back.

So, I thought I was missing steps and thus I dropped the steps in the RA axis from 64, to 32, then to 16, and then even down to 8.  No change.  As such I thought maybe the current was too low for this massive motor.  So I increased it from 700 IRUN, to 900, to 1400, to 2000, to 2500....No change.

The mount is massive, and I have a 100 tooth to 20 tooth (5:1) belt reduction (image below).  I think I will try a 60 tooth and 20 tooth reduction tonight and see if that helps? 

I then thought maybe this was a master branch issue and switched to 3.16....no change

But if anyone (Howard specifically) knows for sure what's happening please let me know. Maybe I am on the wrong track.  I also have an extra motor (same one) I can swap, as well as a couple smaller ones.  I don't think anyone has used a motor this big on an OnStep project yet, but I don't see why it should not work (again Howard please let me know).

Thanks in advance!

















"Guilherme Vênere
 

Are you sure the motors are going in the right direction? If you leave the scope without guiding is it really going east->west? I remember seeing something similar with my Losmandy before i installed OnStep, but it was the 492 controller set up for south hemisphere while im in the north now. I thought the guiding was horrible until i noticed it was going to the wrong side :)

Guilherme

On Thu, Nov 12, 2020 at 2:46 PM Rockmover <kruse@...> wrote:

I finally got around to testing the AP1200 mount and OnStep step. 

However, I have an issue which I "believe" is the RA motor is missing steps when it is just normally tracking.  Below are the PHD2 graphs.  I can slew all over the sky as much as I like and the mount works fine.  Targets are all pretty close, and when I go back to the original spot I am pretty much dead on.  So for that reason I "don't" think I am missing steps otherwise I would think slewing would also be off?  But I am not sure?

My polar alignment is spot on. I am using drift alignment for 10+ minutes, and the AP is on a concrete pier, so nothing is moving.  I also checked polar alignment using a Polemaster, and again it was spot on.

BUT, if I try guiding the RA axis is always forcing steps to keep up (image below).  In fact if I got for 10 minutes the RA corrections will be a set of solid blue correction bars all in the vertical direction.  Furthermore, if I go into guiding assistant in PHD2, the second guiding is turned off, the RA drops like a rock (again image below second red arrow).  This is not PE error as it doesn't come back.

So, I thought I was missing steps and thus I dropped the steps in the RA axis from 64, to 32, then to 16, and then even down to 8.  No change.  As such I thought maybe the current was too low for this massive motor.  So I increased it from 700 IRUN, to 900, to 1400, to 2000, to 2500....No change.

The mount is massive, and I have a 100 tooth to 20 tooth (5:1) belt reduction (image below).  I think I will try a 60 tooth and 20 tooth reduction tonight and see if that helps? 

I then thought maybe this was a master branch issue and switched to 3.16....no change

But if anyone (Howard specifically) knows for sure what's happening please let me know. Maybe I am on the wrong track.  I also have an extra motor (same one) I can swap, as well as a couple smaller ones.  I don't think anyone has used a motor this big on an OnStep project yet, but I don't see why it should not work (again Howard please let me know).

Thanks in advance!

















Khalid Baheyeldin
 

The TMC2130 is usable to 1200 mA only.
So setting them to higher than that is not good, and can even be dangerous.
Also, I assume that you set the potentiometer all the way up before starting to use IRUN/IGOTO in Config.h.
Otherwise, the current you specify in Config.h is not what you end up with.

Another thing is when you changed the _DRIVER_MICROSTEPS, did you change STEPS_PER_DEGREE accordingly
to what the spreadsheet said?


Khalid Baheyeldin
 

Another thing: what board are you using?
Some boards require microstepping to be set by jumpers, while others allow it to be in Config.h.
If you use a jumper board, and rely on microstepping in Config.h without changing the physical
jumpers, while changing steps per degree, you will get speed issues, since there will be mismatch.


Howard Dutton
 

I see the Declination axis drifting off pretty rapidly, makes me wonder about that polar alignment.

My "Max" type controller can do up to about 1400mA (peak) with TMC2130's if built according to my directions.  The SSS TMC2130 can in theory handle up to 1700mA (peak) but that's unobtainable due to thermal issues in my experience.


Rockmover
 

Thanks Howard and Khalid for the feedback, 

Last night I ripped off the motor on my G11 (PKP246MD15A2) and put it on the DEC axis of the AP1200 mount. This is the same motor I have on my RA axis. 

I also took the MAXPCB board from the G11, uploaded the new firmware for the AP, and put that on the AP1200. Technically it's the same construction, but this way I can completely remove anything about that as I know the G11 board works great.

As I mentioned I drift aligned, and all was good, but to be safe I also threw the polemaster back on and checked everything.  Alignment was still almost spot on.

Then came the moment of truth...I started guiding and was about 0.65' which is ok....BUT all RA corrections were still in the exact same direction, and it was correcting every single step. I went to PHD2 guiding assistant, and like clockwork the second it stopped tracking (eg correcting that RA error) it quickly drifted right off the screen.

As such I now know it has nothing to do with the motor (actually I have two of the large motors and tried both the night before, I have tried three of them on the AP1200 all the same result).

I know it is not the MaxPCB board as two completely different ones give the exact same results.

So all I have left is software....

The AstroPhysics AP1200 mount has 225 main gear teeth on BOTH the DEC and RA axis.

I physically counted all 100 teeth, and 20 teeth last night on my GT2 pulleys for the RA worm drive and motor. So that ratio is 5:1...no question.

With the smaller motor giving the same results as the larger one, and the fact I have a tiny 80 mm scope (now on this massive AP1200 mount) with a small mono ZWO camera the load is <15 lbs total (nothing compared to my 16830 and Stellarvue setup).  As such I do not believe motor current is the issue. I "feel" 800 mA for IRUN should be fine for the TCM2130, and the other settings I will let Onstep default to based on this.

With the above can you guys please verify that the spreadsheet and settings below are correct. 

As the slewing around the sky seems to work just fine, I keep coming back to the only thing left being somehow the RA motor is running to slow??  Can my clock be off?  I am using PPS. 

Is there a way to set the motor speed during tracking a tiny bit faster?  On the web screen there is a option for this but I am unsure if clicking this keeps adding to the current speed, or is it just +0.02, -0.02, or off?  In other words if I click it 5 times is it now 0.1 Hz faster?  Or should I just change the "AXIS1_STEPS_PER_WORMROT" value in the spreadsheet to do this?  Do I have this value wrong?

I am running out of options and the next step is to pulley this mount off the pier and put on something else for the meanwhile and new moon cycle.  After so much work, I just hate to not sort this darn thing out.

Thanks in advance...












And my complete config.h file (just in case I have something else wrong)



// ---------------------------------------------------------------------------------------------------------------------------------
// Configuration for OnStep
 
/*
 *          For more information on setting OnStep up see http://www.stellarjourney.com/index.php?r=site/equipment_onstep 
 *                      and join the OnStep Groups.io at https://groups.io/g/onstep
 * 
 *           *** Read the compiler warnings and errors, they are there to help guard against invalid configurations ***
*/
 
// ---------------------------------------------------------------------------------------------------------------------------------
// ADJUST THE FOLLOWING TO CONFIGURE YOUR CONTROLLER FEATURES ----------------------------------------------------------------------
// <-Req'd = always must set, <-Often = usually must set, Option = optional, Adjust = adjust as req'd, Infreq = infrequently changed
 
// PINMAP ---------------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#PINMAP
//   *** See the matching Pins.xxx.h file for your setup (found by looking in src/pinmaps/Models.h) with detailed information ***
//   *** to be sure it matches your wiring.            *** USE AT YOUR OWN RISK ***                                           ***
 
//      Parameter Name              Value   Default  Notes                                                                      Hint
#define PINMAP                        MaxPCB2 //    OFF, Choose from: MiniPCB, MiniPCB2, MaxPCB, MaxPCB2, STM32Blue,             <-Req'd
                                          //         Ramps14, MaxESP2, MaxESP3.  Check Constants.h for more info.
 
// SERIAL PORTS ---------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#SERIAL
#define SERIAL_A_BAUD_DEFAULT        9600 //   9600, n. Where n=9600,19200,57600,115200 (common baud rates.)                  Infreq
#define SERIAL_B_BAUD_DEFAULT        9600 //   9600, n. See (src/HAL/) for your MCU Serial port # etc.                        Option
#define SERIAL_B_ESP_FLASHING         OFF //    OFF, ON Upload ESP8266 WiFi firmware through SERIAL_B with :ESPFLASH# cmd.    Option
#define SERIAL_C_BAUD_DEFAULT         OFF //    OFF, n, ON for ESP32 Bluetooth.                                               Option
#define SERIAL_C_BLUETOOTH_NAME  "OnStep" // "On..", Bluetooth device name for ESP32.                                         Option
 
// MOUNT TYPE -------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#MOUNT_TYPE
#define MOUNT_TYPE                    GEM //    GEM, GEM for German Equatorial, FORK for Equatorial Fork, or ALTAZM          <-Req'd
                                          //         Dobsonian etc. mounts. GEM Eq mounts perform meridian flips.
 
// USER FEEDBACK -------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#USER_FEEDBACK
#define LED_STATUS                     ON //     ON, Blinks w/sidereal tracking otherwise steady on indicates activity.       Option
#define LED_STATUS2                   ON //    OFF, ON Blinks 1s interval w/PPS sync, steady for gotos, off if in standby.   Option
#define LED_RETICLE                   OFF //    OFF, n. Where n=0..255 (0..100%) activates feature sets default brightness.   Option
#define BUZZER                        ON //    OFF, ON, n. Where n=100..6000 (Hz freq.) for piezo speaker. ON for buzzer.    Option
#define BUZZER_STATE_DEFAULT          ON //    OFF, ON Start with piezo buzzer/speaker enabled.                              Option
 
// TIME AND LOCATION -------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#TLS
#define TIME_LOCATION_SOURCE          DS3231 //    OFF, DS3231 (I2c,) DS3234 (Spi,) TEENSY (T3.2 internal,) or GPS source.       Option
                                          //         Provides Date/Time, and if available, PPS & Lat/Long also.
 
// SENSORS -------------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#SENSORS
// * = also supports ON_PULLUP or ON_PULLDOWN to activate MCU internal resistors if present.
#define WEATHER                       OFF //    OFF, BME280 (I2C 0x77,) BME280_0x76, BME280_SPI (see pinmap for CS.)          Option
                                          //         Provides temperature, pressure, humidity.
 
#define TELESCOPE_TEMPERATURE         OFF //    OFF, DS1820 for telescope temperature on one wire interface.                  Option
 
#define HOME_SENSE                    OFF //    OFF, ON*. Automatically detect and use home switches. For GEM mode only.      Option
#define HOME_SENSE_STATE_AXIS1       HIGH //   HIGH, State when clockwise of home position, as seen from front. Rev. w/LOW.   Adjust
#define HOME_SENSE_STATE_AXIS2       HIGH //   HIGH, State when clockwise of home position, as seen from above. Rev. w/LOW.   Adjust
                                          //         Signal state reverses when travel moves ccw past the home position.
 
#define LIMIT_SENSE                   OFF //    OFF, ON* limit sense switch close to Gnd stops gotos and/or tracking.         Option
#define LIMIT_SENSE_STATE             LOW //    LOW, For NO (normally open) switches, HIGH for NC (normally closed.)          Adjust
#define PEC_SENSE                     OFF //    OFF, ON*, n, sense digital OR n=0 to 1023 (0 to 3.3V or 5V) analog threshold. Option
#define PEC_SENSE_STATE              HIGH //   HIGH, Senses the PEC signal rising edge or use LOW for falling edge.           Adjust
                                          //         Ignored in ALTAZM mode.
 
#define PPS_SENSE                     ON //    OFF, ON* enables PPS (pulse per second,) senses signal rising edge.           Option
                                          //         Better tracking accuracy especially for Mega2560's w/ceramic resonator.
 
// ST4 INTERFACE ------------------------------------------------------ see https://onstep.groups.io/g/main/wiki/6-Configuration#ST4
// *** It is up to you to verify the interface meets the electrical specifications of any connected device, use at your own risk ***
#define ST4_INTERFACE                 ON //    OFF, ON, ON_PULLUP enables interface. <= 1X guides unless hand control mode.  Option
                                          //         During goto btn press: aborts slew or continue meridian flip pause home
#define ST4_HAND_CONTROL              ON //    OFF, ON for hand controller special features and SHC support.                 Option
                                          //         Hold [E]+[W] btns >2s: Guide rate   [E]-  [W]+  [N] trk on/off [S] sync
                                          //         Hold [N]+[S] btns >2s: Usr cat item [E]-  [W]+  [N] goto [S] snd on/off
#define ST4_HAND_CONTROL_FOCUSER      OFF //    OFF, ON alternate to above: Focuser move [E]f1 [W]f2 [N]-     [S]+            Option
 
// GUIDING BEHAVIOR ----------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#GUIDING
#define GUIDE_TIME_LIMIT                0 //      0, No guide time limit. Or n. Where n=1..120 second time limit guard.       Adjust
#define GUIDE_DISABLE_BACKLASH        OFF //    OFF, Disable backlash takeup during guiding at <= 1X                          Option
 
// TRACKING BEHAVIOUR -------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#TRACKING
#define TRACK_AUTOSTART               ON //    OFF, ON Start with tracking enabled.                                          Option
#define TRACK_REFRACTION_RATE_DEFAULT OFF //    OFF, ON Start w/atmospheric refract. compensation (RA axis/Eq mounts only.)   Option
#define TRACK_BACKLASH_RATE            25 //     25, n. Where n=2..50 (x sidereal rate) during backlash takeup.               Option
                                          //         Too fast motors stall/gears slam or too slow and sluggish in backlash.
 
// SYNCING BEHAVIOUR ---------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#SYNCING
#define SYNC_CURRENT_PIER_SIDE_ONLY    OFF //     ON, Disables ability of sync to change pier side, for GEM mounts.            Option
 
// SLEWING BEHAVIOUR ---------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#SLEWING
#define SLEW_RATE_BASE_DESIRED        2.0 //    1.0, n. Desired slew rate in deg/sec. Adjustable at run-time from            <-Req'd
                                          //         1/2 to 2x this rate, and as MCU performace considerations require.
#define SLEW_RATE_MEMORY              OFF //    OFF, ON Remembers rates set across power cycles.                              Option
#define SLEW_ACCELERATION_DIST        5.0 //    5.0, n, (degrees.) Approx. distance for acceleration (and deceleration.)      Adjust
#define SLEW_RAPID_STOP_DIST          2.5 //    2.0, n, (degrees.) Approx. distance required to stop when a slew              Adjust
                                          //         is aborted or a limit is exceeded.
                                          
#define MFLIP_SKIP_HOME               OFF //    OFF, ON Goto directly to the destination without visiting home position.      Option
#define MFLIP_PAUSE_HOME_MEMORY       OFF //    OFF, ON Remember meridian flip pause at home setting across power cycles.     Option
#define MFLIP_AUTOMATIC_MEMORY        OFF //    OFF, ON Remember automatic meridian flip setting across power cycles.         Option
 
// PARKING BEHAVIOUR ---------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#PARKING
#define STRICT_PARKING                OFF //    OFF, ON Un-parking is only allowed if successfully parked.                    Option
 
// MOTION CONTROL -------------------------------------------------- see https://onstep.groups.io/g/main/wiki/6-Configuration#MOTION
#define STEP_WAVE_FORM             SQUARE // SQUARE, PULSE Step signal wave form faster rates. SQUARE best signal integrity.  Adjust
 
// Stepper driver models (also see ~/OnStep/src/sd_drivers/Models.h for additional infrequently used models and more info.): 
// A4988, DRV8825, LV8729, S109, SSS TMC2209*, TMC2130* **, and TMC5160* ***
// * = add _QUIET (stealthChop tracking) or _VQUIET (stealthChop tracking & slew,) for example "TMC2130_VQUIET"
// ** = SSS TMC2130 if you choose to set stepper driver current (in mA) set Vref pot. 2.5V instead of by motor current as usual.
// *** = SSS TMC5160 you must set stepper driver current (in mA) w/ #define AXISn_TMC_IRUN (IHOLD, etc.)
 
// AXIS1 RA/AZM
// see https://onstep.groups.io/g/main/wiki/6-Configuration#AXIS1
#define AXIS1_STEPS_PER_DEGREE    20000.0 //  12800, n. Number of steps per degree:                                          <-Req'd
                                          //         n = (stepper_steps * micro_steps * overall_gear_reduction)/360.0
#define AXIS1_STEPS_PER_WORMROT     32000  //  12800, n. Number of steps per worm rotation (PEC Eq mode only:)                <-Req'd
                                          //         n = (AXIS1_STEPS_PER_DEGREE*360)/reduction_final_stage
 
#define AXIS1_DRIVER_MODEL            TMC2130 //    OFF, (See above.) Stepper driver model.                                      <-Often
#define AXIS1_DRIVER_MICROSTEPS       16 //    OFF, n. Microstep mode when tracking.                                        <-Often
#define AXIS1_DRIVER_MICROSTEPS_GOTO  8 //    OFF, n. Microstep mode used during gotos.                                     Option
#define AXIS1_DRIVER_IHOLD            OFF //    OFF, n, (mA.) Current during standstill. OFF uses IRUN/2.0                    Option
#define AXIS1_DRIVER_IRUN             1600 //    OFF, n, (mA.) Current during tracking, appropriate for stepper/driver/etc.    Option
#define AXIS1_DRIVER_IGOTO            OFF //    OFF, n, (mA.) Current during slews. OFF uses same as IRUN.                    Option
#define AXIS1_DRIVER_REVERSE          OFF //    OFF, ON Reverses movement direction, or reverse wiring instead to correct.   <-Often
#define AXIS1_DRIVER_STATUS           OFF //    OFF, TMC_SPI, HIGH, or LOW.  Polling for driver status info/fault detection.  Option
 
#define AXIS1_LIMIT_UNDER_POLE        180 //    180, n. Where n=150..180 (degrees.) Max HA hour angle + or - for Eq modes.    Adjust
#define AXIS1_LIMIT_MAXAZM            360 //    360, n. Where n=180..360 (degrees.) Max Azimuth + or - for AltAzm mode only.  Adjust
 
// AXIS2 DEC/ALT
// see https://onstep.groups.io/g/main/wiki/6-Configuration#AXIS2
#define AXIS2_STEPS_PER_DEGREE    32000.0 //  12800, n. Number of steps per degree:                                          <-Req'd
                                          //         n = (stepper_steps * micro_steps * overall_gear_reduction)/360.0
 
#define AXIS2_DRIVER_MODEL            TMC2130 //    OFF, (See above.) Stepper driver model.                                      <-Often
#define AXIS2_DRIVER_MICROSTEPS       32 //    OFF, n. Microstep mode when tracking.                                        <-Often
#define AXIS2_DRIVER_MICROSTEPS_GOTO  8 //    OFF, n. Microstep mode used during gotos.                                     Option
#define AXIS2_DRIVER_IHOLD            OFF //    OFF, n, (mA.) Current during standstill. OFF uses IRUN/2.0                    Option
#define AXIS2_DRIVER_IRUN             800 //    OFF, n, (mA.) Current during tracking, appropriate for stepper/driver/etc.    Option
#define AXIS2_DRIVER_IGOTO            OFF //    OFF, n, (mA.) Current during slews. OFF uses same as IRUN.                    Option
#define AXIS2_DRIVER_POWER_DOWN       OFF //    OFF, ON Powers off 10sec after movement stops or 10min after last<=1x guide.  Option
#define AXIS2_DRIVER_REVERSE          ON //    OFF, ON Reverses movement direction, or reverse wiring instead to correct.   <-Often
#define AXIS2_DRIVER_STATUS           OFF //    OFF, TMC_SPI, HIGH, or LOW.  Polling for driver status info/fault detection.  Option
#define AXIS2_TANGENT_ARM             OFF //    OFF, ON +limit range below. Set cntr w/[Reset Home] Return cntr w/[Find Home] Infreq
 
#define AXIS2_LIMIT_MIN               -91 //    -91, n. Where n=-91..0 (degrees.) Minimum allowed declination.                Infreq
#define AXIS2_LIMIT_MAX                91 //     91, n. Where n=0..91 (degrees.) Maximum allowed declination.                 Infreq
 
// AXIS3 ROTATOR
// see https://onstep.groups.io/g/main/wiki/6-Configuration#AXIS3
#define ROTATOR                       OFF //    OFF, ON to enable the rotator (or de-rotator for ALTAZM mounts.)              Option
#define AXIS3_STEPS_PER_DEGREE       64.0 //   64.0, n. Number of steps per degree for rotator/de-rotator.                    Adjust
                                          //         Alt/Az de-rotation: n = (num_circumference_pixels * 2)/360, minimum
#define AXIS3_STEP_RATE_MAX           8.0 //    8.0, n, (millisec.) Minimum ms/step depends on processor.                     Adjust
 
#define AXIS3_DRIVER_MODEL            OFF //    OFF, TMC2130, TMC5160. Leave OFF for all drivers models except these.         Option
#define AXIS3_DRIVER_MICROSTEPS       OFF //    OFF, n. Microstep mode when tracking.                   For TMC2130, TMC5160. Option
#define AXIS3_DRIVER_IHOLD            OFF //    OFF, n, (mA.) Current standstill. OFF uses IRUN/2.0.                  "       Option
#define AXIS3_DRIVER_IRUN             OFF //    OFF, n, (mA.) Current tracking, appropriate for stepper/driver/etc.   "       Option
#define AXIS3_DRIVER_POWER_DOWN       OFF //    OFF, ON Powers off the motor at stand-still.                                  Option
#define AXIS3_DRIVER_REVERSE          OFF //    OFF, ON Reverses movement direction, or reverse wiring instead to correct.    Option
 
#define AXIS3_LIMIT_MIN              -180 //   -180, n. Where n=-360..0 (degrees.) Minimum allowed rotator angle.             Infreq
#define AXIS3_LIMIT_MAX               180 //    180, n. Where n=0..360 (degrees.) Maximum allowed rotator angle.              Infreq
 
// AXIS4 FOCUSER 1
// see https://onstep.groups.io/g/main/wiki/6-Configuration#AXIS4
#define FOCUSER1                      OFF //    OFF, ON to enable this focuser.                                               Option
#define AXIS4_STEPS_PER_MICRON        0.5 //    0.5, n. Steps per micrometer. Figure this out by testing or other means.      Adjust
#define AXIS4_STEP_RATE_MAX           8.0 //    8.0, n, (millisec.) Min. ms/step depends on processor. In DC mode, PWM freq.  Adjust
 
#define AXIS4_DRIVER_MODEL            OFF //    OFF, TMC2130, TMC5160. Leave OFF for all drivers models except these.         Option
#define AXIS4_DRIVER_MICROSTEPS       OFF //    OFF, n. Microstep mode when tracking.                   For TMC2130, TMC5160. Option
#define AXIS4_DRIVER_IHOLD            OFF //    OFF, n, (mA.) Current standstill. OFF uses IRUN/2.0.                  "       Option
#define AXIS4_DRIVER_IRUN             OFF //    OFF, n, (mA.) Current tracking, appropriate for stepper/driver/etc.   "       Option
#define AXIS4_DRIVER_POWER_DOWN       OFF //    OFF, ON Powers off the motor at stand-still.                                  Option
#define AXIS4_DRIVER_REVERSE          OFF //    OFF, ON Reverses movement direction, or reverse wiring instead to correct.    Option
#define AXIS4_DRIVER_DC_MODE          OFF //    OFF, DRV8825 for pwm dc motor control on stepper driver outputs.              Option
 
#define AXIS4_LIMIT_MIN_RATE           10 //     10, n. Where n=1..1000 (um/s.) Minimum microns/second. In DC mode, min pwr.  Adjust
#define AXIS4_LIMIT_MIN                 0 //      0, n. Where n=0..500 (millimeters.) Minimum allowed position.               Adjust
#define AXIS4_LIMIT_MAX                50 //     50, n. Where n=0..500 (millimeters.) Maximum allowed position.               Adjust
 
// AXIS5 FOCUSER 2
// see https://onstep.groups.io/g/main/wiki/6-Configuration#AXIS5
#define FOCUSER2                      OFF //    OFF, ON to enable this focuser.                                               Option
#define AXIS5_STEPS_PER_MICRON        0.5 //    0.5, n. Steps per micrometer. Figure this out by testing or other means.      Adjust
#define AXIS5_STEP_RATE_MAX           8.0 //    8.0, n, (millisec.) Min. ms/step depends on processor. In DC mode, PWM freq.  Adjust
 
#define AXIS5_DRIVER_MODEL            OFF //    OFF, TMC2130, TMC5160. Leave OFF for all drivers models except these.         Option
#define AXIS5_DRIVER_MICROSTEPS       OFF //    OFF, n. Microstep mode when tracking.                   For TMC2130, TMC5160. Option
#define AXIS5_DRIVER_IHOLD            OFF //    OFF, n, (mA.) Current standstill. OFF uses IRUN/2.0.                  "       Option
#define AXIS5_DRIVER_IRUN             OFF //    OFF, n, (mA.) Current tracking, appropriate for stepper/driver/etc.   "       Option
#define AXIS5_DRIVER_POWER_DOWN       OFF //    OFF, ON Powers off the motor at stand-still.                                  Option
#define AXIS5_DRIVER_REVERSE          OFF //    OFF, ON Reverses movement direction, or reverse wiring instead to correct.    Option
#define AXIS5_DRIVER_DC_MODE          OFF //    OFF, DRV8825 for pwm dc motor control on stepper driver outputs.              Option
 
#define AXIS5_LIMIT_MIN_RATE           10 //     10, n. Where n=1..1000 (um/s.) Minimum microns/second. In DC mode, min pwr.  Adjust
#define AXIS5_LIMIT_MIN                 0 //      0, n. Where n=0..500 (millimeters.) Minimum allowed position.               Adjust
#define AXIS5_LIMIT_MAX                50 //     50, n. Where n=0..500 (millimeters.) Maximum allowed position.               Adjust
 
// THAT'S IT FOR USER CONFIGURATION!
 
// -------------------------------------------------------------------------------------------------------------------------
#define FileVersionConfig 3






Lloyd Simons
 

It looks like there is a mismatch in AXIS2_STEPS_PER_DEGREE from the spreadsheet and the config.h. One is 24000 the other is 32000.


Khalid Baheyeldin
 

On Fri, Nov 13, 2020 at 01:59 PM, Lloyd Simons wrote:
It looks like there is a mismatch in AXIS2_STEPS_PER_DEGREE from the spreadsheet and the config.h. One is 24000 the other is 32000.
Good catch.

That does not explain why RA is also off.

Rockmover, if you use the online configuration generator, it will calculate steps per degree for you from the spreadsheet parameters, so there should be no discrepancy.


Rockmover
 

Thanks and yes, the RA is wrong in the post. I have about 15 config.h files I have been trying and going back it looks like I mistyped that one at revision 13 last night at about 4 am....

What I am going to do tonight is simply change the "AXIS1_STEPS_PER_WORMROT" from 32000 to 34000 and see what happens in the PHD2 guiding assistant. 

If its get worse faster then I will make it 29000 and try again.  With a few points I "should" be able to adjust the speed to match what I need??? 

It certainly seems that this should be the exact same as the adjusting the tracking rate in the web interface, but  does anyone know if that button is additive, and thus keeps changing each time you click it? I played with it the other night and it didn't seem to have any effect.  Anywhere you can see what the actual value is set at??


Khalid Baheyeldin
 

On Fri, Nov 13, 2020 at 05:23 PM, Rockmover wrote:
What I am going to do tonight is simply change the "AXIS1_STEPS_PER_WORMROT" from 32000 to 34000 and see what happens in the PHD2 guiding assistant. 

AXIS1_STEPS_PER_WORMROT is only used if you record and playback PEC.
If you are not using PEC at all, and sure enough the Astro-Physics should have low PE, then you don't need that parameter, nor PEC, since you rely on autoguiding anyways.

So set that paramter to 0.

What matters for fast/slow tracking is AXIS1 and AXIS2_STEPS_PER_DEGREE.

If its get worse faster then I will make it 29000 and try again.  With a few points I "should" be able to adjust the speed to match what I need??? 

It certainly seems that this should be the exact same as the adjusting the tracking rate in the web interface, but  does anyone know if that button is additive, and thus keeps changing each time you click it? I played with it the other night and it didn't seem to have any effect.  Anywhere you can see what the actual value is set at??
You should not have to adjust the tracking rate.
There is a mismatch somewhere, and it needs to be corrected: somewhere between GR1 or GR2, Microsteps, or steps per degree.
Fix that, and you don't need any other gimmicks.


Howard Dutton
 
Edited

I tested your exact Config.h on a MaxPCB2 (T3.5) running the latest OnStep master (4.21f).  As some have noticed the master branch has a redesign of TMC micro-step mode switching and though I performed this test with AXISn_DRIVER_MICROSTEPS_GOTO as you had them set feel free to set them to OFF to disable some of this newer code and improve the likelihood of avoiding a bug if one exists in this new code perhaps.  Note that I know of no bugs (with patch level "f" today) and things appear to be working properly in my tests and measurements.  I also checked the tracking frequency with this exact setup and release-3.16 the results were exactly the same.

The RA drift rate from PHD2 in your image is 0.57 arc-sec/second.  So, for instance, if that is fast this implies a tracking rate of 15.041 + 0.57 = 15.611 arc-sec/second.  As a ratio that's 15.611/15.041 = 1.038x too fast.

The frequency required is (20000/240)*1.00273790935 = 83.56149 Hz.  As a reality check multiply by our ratio 83.56149 * 1.038 and we should be seeing ~ 86.7Hz if running fast or divide and ~80.5Hz if running slow.

My DS1054 Oscilloscope reports that as 83.6Hz on the Axis1 driver step pin as expected (one decimal place is the limit of its accuracy here:)



I also timed a complete rotation of a 400 step motor during sidereal tracking and came up with 77 seconds...
400 * 16x mode = 6400 steps for a complete rotation of the stepper shaft.  Now 6400/83.56149 = 76.59 seconds.
I wouldn't expect to do better than +/-0.5s for my visually timing this, so I call that good (and obviously solid proof that the stepper driver (TMC2130) is in the right micro-step mode too.)


Wayne Hilliard
 

I noticed in the picture of the guiding Assistant that it's reporting 18.6 arc min of polar alignment. I ran into the same issue with my c8 fork and it acted like this even though my drift aligni g seemed ok. I finally cleaned it up by doing a couple of polemaster sessions and fine tuning the polar alignment.

Wayne Hilliard

On Thu, Nov 12, 2020, 5:46 PM Rockmover <kruse@...> wrote:

I finally got around to testing the AP1200 mount and OnStep step. 

However, I have an issue which I "believe" is the RA motor is missing steps when it is just normally tracking.  Below are the PHD2 graphs.  I can slew all over the sky as much as I like and the mount works fine.  Targets are all pretty close, and when I go back to the original spot I am pretty much dead on.  So for that reason I "don't" think I am missing steps otherwise I would think slewing would also be off?  But I am not sure?

My polar alignment is spot on. I am using drift alignment for 10+ minutes, and the AP is on a concrete pier, so nothing is moving.  I also checked polar alignment using a Polemaster, and again it was spot on.

BUT, if I try guiding the RA axis is always forcing steps to keep up (image below).  In fact if I got for 10 minutes the RA corrections will be a set of solid blue correction bars all in the vertical direction.  Furthermore, if I go into guiding assistant in PHD2, the second guiding is turned off, the RA drops like a rock (again image below second red arrow).  This is not PE error as it doesn't come back.

So, I thought I was missing steps and thus I dropped the steps in the RA axis from 64, to 32, then to 16, and then even down to 8.  No change.  As such I thought maybe the current was too low for this massive motor.  So I increased it from 700 IRUN, to 900, to 1400, to 2000, to 2500....No change.

The mount is massive, and I have a 100 tooth to 20 tooth (5:1) belt reduction (image below).  I think I will try a 60 tooth and 20 tooth reduction tonight and see if that helps? 

I then thought maybe this was a master branch issue and switched to 3.16....no change

But if anyone (Howard specifically) knows for sure what's happening please let me know. Maybe I am on the wrong track.  I also have an extra motor (same one) I can swap, as well as a couple smaller ones.  I don't think anyone has used a motor this big on an OnStep project yet, but I don't see why it should not work (again Howard please let me know).

Thanks in advance!

















Rockmover
 

Thanks Howard, 

I am somewhat at a dead end. Tonight I got the polar alignment under 0.5 seconds in both DEC and RA in PHD2.  In fact with my 7/8" bolts and 1/2" steel plate on that concrete pier its a matter of a tiny nudge of how tight (or very tight) I could tighten the 4 perimeter bolts on the AP mount to tweak it, I went back and forth for a couple hours getting it the best I have personally ever polar aligned a scope.

I can also slew anywhere in the sky and plate solving finds its target spot on the first iteration.

BUT, the minute I guide, or go into guiding assistant the mount does exactly the same thing.  Its lags in RA and just keeps correcting upwards.  The minute I go into guiding assistant it drops like a rock off the screen.

If I had not tried two completely separate OnSteps boards, and both the small and large motors (all with the same result) I would have said its something on my setup. 

But as of now I have no solution, and no clue what to even try next....we have 4 other mounts in the roll off shed and even the cheap EQ-6 makes this AP1200 look like a piece of junk.

Could it be a Arduino compiling issue with the Teensy 3.6?  I'm using 180 MHz (also tried 120) and Optimize Faster, and just "serial" for settings.  This specific board has no focuser, just the two 2130's on it.


John Petterson
 

One other thing to try - start it tracking without guiding, and put your hand on the RA motor to feel if it has any jerkiness.  I have had issues with my mounts being adjusted a bit tight and the motors would miss steps at slow speeds. Stepper motors have great holding torque, but as they move slowly they can be easily bounced backwards a step with resistance. At slew speeds they will succumb to the inertia and not have that problem.  You can usually hear the click as it misses the step as well. I ended up loosening the worm a bit (Losmandy mount) and it tracks well.

John


Rockmover
 

I have felt the RA gear several times.  Also the much smaller motor tracks the exact same, so if it was slipping I'd see a difference.

Also, tonight I swapped in my 5160's....works great, but SAME issue.


Rockmover
 

Here is a typical graph with the 5160's.

I also get the "pulseguide command t mount has failed" error every now and then, but don't know what it means or how to fix it?



"Guilherme Vênere
 

Are you connecting via WiFi/Bluetooth? I had that problem when connecting OnStep to my home WiFi as the signal in the backyard is not strong and during guide it would loose connectivity. 

I had to fall back to using USB to connect to OnStep. After that I didn’t see this error anymore

Guilherme 


On Tuesday, November 17, 2020, Rockmover <kruse@...> wrote:
Here is a typical graph with the 5160's.

I also get the "pulseguide command t mount has failed" error every now and then, but don't know what it means or how to fix it?



Howard Dutton
 

On Thu, Nov 12, 2020 at 02:46 PM, Rockmover wrote:

BUT, if I try guiding the RA axis is always forcing steps to keep up (image below).  In fact if I got for 10 minutes the RA corrections will be a set of solid blue correction bars all in the vertical direction.  Furthermore, if I go into guiding assistant in PHD2, the second guiding is turned off, the RA drops like a rock (again image below second red arrow).  This is not PE error as it doesn't come back.
With PHD2 pulse guiding at 0.25x guide rate (using a camera simulator) I observed on my DS1054 o'scope on the RA axis step pin:

The guide east frequency was 62.6Hz
The normal tracking frequency remained at 83.6Hz.
The guide west frequency was 104Hz.


Howard Dutton
 

I should add I did NOT once see a timing glitch on the o'scope when looking at the tracking.  No strangeness at all.

Turning off the DS3231 and PPS eliminates two possibilities.  Who knows maybe the cheap'o DS3231 is a clone or defective and horribly inaccurate.  Or I2C down in a library is causing trouble though it is not accessed (for time) except at startup normally so that seems like a distant possibility.


Howard Dutton
 

On Tue, Nov 17, 2020 at 11:54 PM, Rockmover wrote:
Here is a typical graph with the 5160's.
In that graph I see ~3 arc second spikes...

Why????  You also posted the spreadsheet calculations with the RA axis tracking in 16x mode and at 0.18 arc-second per step.  A full step = 16 * 0.18 = 2.88 arc seconds.

Is this thing missing steps? 
Is that the driver cutting out in thermal overload protection?