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Re: Push To - reuse intelliscope encoders

kevin
 

Also if you can code for the Pc presumably you could just ave a small prog that intercepts the serial port, and i forgot to add the link to the app note on the subject.  https://www.allegromicro.com/en/insights-and-innovations/technical-documents/hall-effect-sensor-ic-publications/hall-effect-system-with-two-linear-sensor-ics


Re: Push To - reuse intelliscope encoders

kevin
 

Hi Serge,
Thanks for the link , it is most informative. the system is an analog form of quarature  and indeed would need some A/D and software to get it into a suitable form. There is a precision CNC measureing system that it reminds me of where they basically uses precision ground steel balls inside an stainless tube and induction http://www.newall.co.uk/technology/ , also a number of people make low res versions of it with spherical magnets and only use the polarity not the linearity of the magnets https://www.hackster.io/news/magnetic-spheres-link-up-to-form-rotary-encoder-ring-5faaa786048e
However,  If AG has a working handset,  that page mentions that the handset has an RS232 computer interface on it ( be careful joining it to other stuff it will  be + - 6 to12 volts and will destroy ordinary logic) which actually will give you the nunbers for its position in a simple format that works directly with a couple of paid software packages. That may be sufficient for AG .
It should be realivly easy, if no one hasn't done it yet,  to use those numbers instead of the quadrature counted numbers in the arduino program ( will need an arduio with 2 serial ports ,hardawre or software)  is still in Alt Az coordinates and for the LX200 protocol needs translating for Stellarium but maybe a diferent protocol may not even need that.


Re: confusion over settings for stepper motors

Howard Dutton
 
Edited

On Mon, Dec 20, 2021 at 06:23 AM, Howard Dutton wrote:
I'd set the following, good for up to about 3 deg/s slews on an ESP32.   What's shown below can and should be adjusted at runtime to the optimal setting (w/ the website, android app, SHC etc.) from 0.75 deg/s to 3 deg/s.
...I'm talking about testing here.

When settled in on a final figure for the fastest slew rate for normal operations, I suggest setting 1/2 of that rate.  For example if that fastest slew rate for normal operations turns out to be 2.5 deg/s set:
#define SLEW_RATE_BASE_DESIRED       1.25 //    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.


Then I'd enable the slew rate memory so your last runtime setting is remembered:
#define SLEW_RATE_MEMORY               ON //    OFF, ON Remembers rates set across power cycles.                              Option


Re: ESP32 wireless SHC (wSHC)

Drew 🔭📷🚴‍♂️
 
Edited

On Mon, Dec 20, 2021 at 09:29 AM, Martin Bonfiore wrote:
I may ask to pass it by the forum for review before contributing it.  
I would suggest starting a thread over in the Developers group for this.


Re: ESP32 wireless SHC (wSHC)

Martin Bonfiore
 

I will try to do it robustly.  Given I have success, I may ask to pass it by the forum for review before contributing it.  


Re: confusion over settings for stepper motors

Howard Dutton
 
Edited

Hopefully Guy has already taken these measures of cutting off that pin and grounding it (if necessary) so the TMC5160's are connected correctly.

I'm not sure I see evidence that anything is wrong.  AFAIK Guy was trying to slew too fast and needs to slow things down and lower his expectations WRT slew rates.

It seems like slewing was working but a bit rough at 3 deg/s, if so lets say that's near the top end speed the motors can do before they stall.

However that's not where you would typically operate, so slow down a bit to perhaps 1.5 or 2 deg/s as the fastest speed. Or, use 24VDC which should help, perhaps making that 2 to 2.5 deg/s for operation.  Something nice and safe, 100% always works under all conditions.

Note that with stepper motors there can be resonance (electro-mechanical vibration) where some speeds you settle in on have a tendency to run rough while other speeds (even nearby) don't.  Its one thing to accelerate through a resonant frequency range but it's another to sit there and let the effect build to its maximum and listen to it (and accept the reduced torque) during every slew.

I'd set the following, good for up to about 3 deg/s slews on an ESP32.   What's shown below can and should be adjusted at runtime to the optimal setting (w/ the website, android app, SHC etc.) from 0.75 deg/s to 3 deg/s.

The thing I'm least confident about is IGOTO, that might work better higher or lower and hopefully in your experimentation you've figured out which.  Too high and it can encourage that resonance I talked about above, too low and the torque isn't there to begin with.  IRUN doesn't need to be too high (given that 7180:1 reduction you have there) but 800mA seems really low for a 2.8A motor so I went with 1A.

#define SLEW_RATE_BASE_DESIRED        1.5 //    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 STEP_WAVE_FORM              PULSE // SQUARE, PULSE Step signal wave form faster rates. SQUARE best signal integrity.  Adjust

#define AXIS1_STEPS_PER_DEGREE 31911.1111 //  12800, n. Number of steps per degree: 2393    
                                          //         n = (stepper_steps * micro_steps * overall_gear_reduction)/359.0
#define AXIS1_STEPS_PER_WORMROT     32000 //      0, n. Number steps per worm rotation (PEC Eq mode only, 0 disables PEC.)   <-Req'd
                                          //         n = (AXIS1_STEPS_PER_DEGREE*360)/reduction_final_stage
#define AXIS1_DRIVER_MODEL  TMC5160_QUIET //    OFF, (See above.) Stepper driver model.                                      <-Often
#define AXIS1_DRIVER_MICROSTEPS         8 //    OFF, n. Microstep mode when tracking.                                        <-Often
#define AXIS1_DRIVER_MICROSTEPS_GOTO  OFF //    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            1000 //    OFF, n, (mA.) Current during tracking, appropriate for stepper/driver/etc.    Option
#define AXIS1_DRIVER_IGOTO           1500 //    OFF, n, (mA.) Current during slews. OFF uses same as IRUN.                    Option

#define AXIS2_STEPS_PER_DEGREE 31911.1111 //  12800, n. Number of steps per degree: 2393    
                                          //         n = (stepper_steps * micro_steps * overall_gear_reduction)/359.0
#define AXIS2_DRIVER_MODEL  TMC5160_QUIET //    OFF, (See above.) Stepper driver model.                                      <-Often
#define AXIS2_DRIVER_MICROSTEPS         8 //    OFF, n. Microstep mode when tracking.                                        <-Often
#define AXIS2_DRIVER_MICROSTEPS_GOTO  OFF //    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            1000 //    OFF, n, (mA.) Current during tracking, appropriate for stepper/driver/etc.    Option
#define AXIS2_DRIVER_IGOTO           1500 //    OFF, n, (mA.) Current during slews. OFF uses same as IRUN.                    Option


Re: confusion over settings for stepper motors

Guy Brandenburg
 

Ken, 
Thank you again, very much, for the board. 
I cut off that pin before I inserted the TMC5160 driver chips. 
So that's not the problem.

Guy 


Re: Files upload

Drew 🔭📷🚴‍♂️
 

First let me state for the record that is good and needed work! I don't have the time now, but if I can, I will send you a markup with my suggestions and comments.

I am of the school of thought that we should not include one-off fixes in any documentation. I would, for the time being, remove the 10uf cap fix and the discussion about the rst pin. Quite simply, these are issues you may have experienced, but there are no other reports of these problems.

Also, you state that the antenna on the ESP32 is not used. This is not true. It is used for both Bluetooth and WiFi (in OnStepX).

I think the schematic is great work. But like Howard, I do not think it is a new version. I would label it as MaxESP3 - fully annotated.

On Sun, Dec 19, 2021 at 06:37 PM, Howard Dutton wrote:
If this turned out to be a real problem I'd be inclined to drop the ability to flash the WeMos D1 Mini through the ESP32 (remove the Dir2/GPIO0 and RST provision.)  It's a tricky thing to flash through most users don't tackle anyway and so few pins.
I believe this feature should be relegated to the "depreciated". I would not want to remove it from the code. Just remove it from the documentation and put a "depreciated" label in the code and any references to it.


Re: confusion over settings for stepper motors

Howard Dutton
 

On Mon, Dec 20, 2021 at 02:12 AM, Ken Hunter wrote:
On the MaxESP3 page the image shows TMC5160 drivers installed. They have a resistor from pin 6 to GND.
There is no text associated with the MaxESP3 build that I have found that says to cut this pin, just the following
basic description shown below........Here's the info on the TMC 5160 Drivers. It wasn't easy to find in the Wiki.
I figured that was fairly clear in the MaxESP3 Wiki stepper driver section (shown below):

Choice of Stepper driver: Axis1/2 (RA/Dec or Azm/Alt):
  • SilentStepStick TMC2130 or TMC5160 (read about these drivers before buying!) are the most advanced stepper drivers supported (operating in SPI mode) and are the recommended drivers.


Re: Files upload

Howard Dutton
 

On Mon, Dec 20, 2021 at 03:44 AM, Howard Dutton wrote:
On Sun, Dec 19, 2021 at 01:53 PM, Robert Benward wrote:
The schematic is a MaxESP V3, with two build changes.  One is the C12 capacitor value, which I noted and changed to 0.1uF.  It no longer interferes with the reset of the WEMOS when enabling the SPI, providing me with driver status.  I am hoping George can validate that change.   
I really don't understand the mechanism here that fixes the WeMos D1 Mini (not booting?)  Guess its the delay with bringing up the ESP32?

I'm fine with changing that capacitor if its a valid fix, kind of a minor thing and no downside if its an improvement.
For reference, about that 10uF cap:

https://github.com/espressif/arduino-esp32/issues/1497


Re: Push To - reuse intelliscope encoders

Serge Antonov
 

Hi Kevin,

The encoders installed on Orion telescopes with Intelliscope are not conventional quadrature encoders. Each of those encoders consists of two simple Hall effect sensors and a multi-pole magnetic ring. In order to be able to use those encoders one would need to connect the Hall effect sensors to an ADC and then convert sine waves to a quadrature signal.

For more information please refer to the following page: https://web.archive.org/web/20100105011604/http://maxwell.fief.org/intelliscope.html

Best Regards,
Serge.

On 20 Dec 2021, at 1:27 pm, kevin_kevin_kevin via groups.io <kevin_kevin_kevin@...> wrote:

Hi Serge,
I don't know about Orion scopes and they may come in different forms but from "IntelliScope_Control_RevB.pdf"  instalation manual  i have read  that they are  the IntelliScope’s high-resolution, 9,216-step digital encoders and are magnetic with 2 magnetic sensors so it is almost certainly a quadrature signal system but it would really need a working system and someone with a oscilloscope or logic analyser and a bit of electronics know how to see exactly how they work. Is it somthing that a lot of people would like to do or have already done. any links would be usefull.


Re: Files upload

Howard Dutton
 

On Sun, Dec 19, 2021 at 01:53 PM, Robert Benward wrote:
The schematic is a MaxESP V3, with two build changes.  One is the C12 capacitor value, which I noted and changed to 0.1uF.  It no longer interferes with the reset of the WEMOS when enabling the SPI, providing me with driver status.  I am hoping George can validate that change.   
I really don't understand the mechanism here that fixes the WeMos D1 Mini (not booting?)  Guess its the delay with bringing up the ESP32?

I'm fine with changing that capacitor if its a valid fix, kind of a minor thing and no downside if its an improvement.


Re: confusion over settings for stepper motors

Ken Hunter
 

Guy...

I provided you a working MaxESP3 OnStep board using LV8729 stepper drivers with a lifetime guarantee.
And free online or telephone assistance. I turn 75 this Tuesday so not much of a guarantee LOL

I also offer a full refund of your purchase price if not completely satisfied.
Since it was donated, just send it back and I'll refund no money.

Also the unpublished warrantee is void if the device is modified, connected to anything  or removed
from the shipping package. Sucks to be you ;0)

Merry Christmas


Re: confusion over settings for stepper motors

Ken Hunter
 


On the MaxESP3 page the image shows TMC5160 drivers installed. They have a resistor from pin 6 to GND.
There is no text associated with the MaxESP3 build that I have found that says to cut this pin, just the following
basic description shown below.



Here's the info on the TMC 5160 Drivers. It wasn't easy to find in the Wiki.

TMC5160:

These drivers come with pins either loose (you solder them) or both up and down so will work with any OnStep. Some versions may require some modifications to work.  They all come with the SPI interface enabled.  Also, they usually don't require any heat-sinks. 

The Watterott brand TMC5160 v1.3 drivers need the CLK pin grounded and also cut off so it doesn't plug in.  Distributed through Digikey in the US (without pins installed.)  They are tested and known to work.

The Watterott brand TMC5160 v1.4 and v1.5 drivers only need the DCO pin cut off so it doesn't plug in.  These are expected to work but are untested.

The BigTreeTech TMC5160 v1.2 drivers only need the CLK pin cut off so it doesn't plug in.  A few users have reported that they work without any other modifications. Only one user reported that he still had to use a wire to connect CLK to GND.

The FYSETC brand TMC5160 v1.2 drivers need the CLK pin grounded and cut off so it doesn't plug in.  These are expected to work but are untested.


Re: Files upload

Apollo Grandad (Paul)
 

Bob,

Thanks for the annotated schematic - it helps me understand the flexible  nature of the design. 

A few points:
I can't see a regulator for 3.3V. So net "3V3" is confusing.

Reverse voltage may fry everything, the diodes that pulldown the regulated voltage will conduct. There are power mosfets that can short reverse supplies and blow a fuse or trip a dc circuit breaker. Solar chargers use that design, as it's too easy to get battery connections reversed. An inline low voltage drop "diode" would help.

The CLK signals need to be grounded, there could be a lot of switching noise that affects the pin. Eliminating that helps when systematically testing problems.

Thanks
Paul


Re: confusion over settings for stepper motors

Ken Hunter
 

Guy...

Cut the pin on the bottom side of the TMC 5160 driver board as shown.


Re: Push To - reuse intelliscope encoders

Ken Hunter
 

There is a commercial project called "PUSH TO" which I purchased 2 kits myself for the Apertura scope I bought.

https://romer-optics-llc.myshopify.com/collections/easy-push-to/products/ez-push-to-kit-for-brands-of-dobsonian

They work great right out of the box with Stellarium. Since converting to OnStep to get GOTO, I have not used the one I attached to the scope and the other is in it's unopened box. If you want them give me a shout and we can work something out.

Ken


Re: Files upload

Ken Hunter
 

On Sun, Dec 19, 2021 at 03:31 PM, Howard Dutton wrote:
I judged that cutting the TMC5160 pin is most flexible/easy to understand "universal" advice.
Howard, I haven't looked for this but i hope that it id prominently posted as I have been trying to
get a MaxESP3 working with the 5160 drivers on line and through phone contact with Guy from
Hopewell Observatory.

Could this be the reason Guy is having so much problems for his build in GOTO mode? I am
very far behind the learning curve for the TMC drivers so it may be there in BOLD RED print
but I have skipped over much of the TMC info so far and I have not removed the pins 5&6
connection on their build.


Re: confusion over settings for stepper motors

Ken Hunter
 

On Sun, Dec 19, 2021 at 01:37 PM, Khalid Baheyeldin wrote:
If this is successful, you can retain the existing 20:1 gearbox.
YES I AGREE, lets try troubleshooting this correctly.

No Matter what, he can NOT remove the 20:1 gearset that drives the 359:1 RA axis. It is cast in steel by BYERS himself.
That will always be a permanent given 359 X 20 = Total gear ratio of 7180.

Adding to that the following choices of microstepping.

200 steps X 16 = 3200
200 steps X 32 = 6400
200 steps x 64 = 12,800

Those are his choices.

His goal is to use the telescope.

Guy says the TRACKING is OK and the motors are quiet (but a bit slow I think).
So for the tracking situation there is a baseline working, good movement and quiet. 

When he is trying to SLEW or GOTO the steppers misbehave.
I am believing that there is something wrong with the physical/electrical changes that
happen between TRACKING and SLEWING speeds in the stepper driver/stepper configuration.

I don't know if Guy can change the tracking and GOTO microsteps to the same setting but if  he
can it would tell a lot about what the OnStep MaxESP3 board is telling the steppers to do during
TRACKING and GOTO.

Bob Benward has posted that a trace needs to be cut on the MaxESP3 board to isolate pins
5 and 6 to use 5160 drivers. I have no experience with TMC SPI drivers on my MaxESP3 boards
but my experiences with Bob have been very positive and I would try cutting that pin to see what
happens. If the pin is cut and it works GREAT, if not Guy can always connect the #5 and 6 pins
together on the top of the 5160 driver circuit card to make it as good as new.


Takahashi , Onstep on Em10 mount

mmo@...
 

Em10 Takahashi mount with Onstep new motor control.
The Phd2 autoguide keep the star well  at subpixel level :
I am happy my 25 year old gear still works !

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