Since I aquired an Losmandy G11 mount without any goto provision I decided to create my own solution. I was a bit reluctant to use a Gemini, mainly because of the cost, but also due to the reliability since the servo motors are somewhat prone to failure. I also like to have complete control over the software/firmware so that no "show stopper" issues will ever be a problem for me. Looking around the 'net I saw other goto systems that seemed capable, but either they had needlessly complex hardware or were commercial systems that cost about twice what they should.
OnStep is a computerized goto system, usually for stepper motor equipped mounts though any step/dir interface motor driver (including servo) should work. It was designed, from the beginning, as a more or less general purpose system and provisions were made in the firmware to allow for use on a variety of mounts including Equatorial and Alt/Az (GEM, Fork, Dobsonian, etc.) It uses an LX200 like computer command set with a few extensions to suit hand controller-less operation.
There's a telescope hand controller App for Android (free in the Google Play Store,) an option to control through a website (Smart Web Server,) and a dedicated physical hand controller (Smart Hand Controller.) Or, on a PC there's ASCOM and INDI drivers for control. These options allow you to setup and control OnStep using a wide range of software including my Sky Planetarium, Cartes du Ciel, Stellarium, SkySafari, KStars, PHD2, etc. You can see most of the control possibilities in the diagram below:
Also, please visit my StellarJourney.comsite for updates, links toOnStep resources, my other astronomy software, or to see someImages taken with the assistance of my OnStep operated mounts.
If you find OnStep useful and would like to show your appreciation and support please consider making asmall monetary donation. This keeps me motivated and helps cover expenses associated with my projects.
No (and Yes).
Yes, Simingx's scope uses Harmonic drives, but he is driving them with a regular motor that has a built in gearbox.
Specifically, it is this motor from Stepper Online.
If he was using
No (and Yes).
Yes, Simingx's scope uses Harmonic drives, but he is driving them with a regular motor that has a built in gearbox.
Specifically, it is this motor from Stepper Online.
If he was using
Simingx's mount build is exceptional. He's using a type of gearbox called Harmonic Drive. Not super common, especially smaller than nema 23, but they have very low to non-existent backlash. Much
Simingx's mount build is exceptional. He's using a type of gearbox called Harmonic Drive. Not super common, especially smaller than nema 23, but they have very low to non-existent backlash. Much
It's really a matter of experimentation. You should have received a data sheet with your motors that identifies the wires that make up the connections to each coil. If not, it's easy to identify the
It's really a matter of experimentation. You should have received a data sheet with your motors that identifies the wires that make up the connections to each coil. If not, it's easy to identify the
You could go a bit more on the reduction.
Keep the belt at 1:1, but go with a motor with either 10:1 or 15:1 reduction.
That makes the motors work considerably less for more torque.
Also increases
You could go a bit more on the reduction.
Keep the belt at 1:1, but go with a motor with either 10:1 or 15:1 reduction.
That makes the motors work considerably less for more torque.
Also increases
Yes, there are 3 CGE conversions in the showcase. All use belt drive but I don't think any are 1:1.
A 5:1 planetary reducer, a 1:1 belt with the native 1:180 worm wheel reduction seems reasonable to
Yes, there are 3 CGE conversions in the showcase. All use belt drive but I don't think any are 1:1.
A 5:1 planetary reducer, a 1:1 belt with the native 1:180 worm wheel reduction seems reasonable to
There is now a Wiki page that covers this topic, I welcome comments and corrections, this is my best understanding of the subject:
https://onstep.groups.io/g/main/wiki/Stepper-Motor-Accuracy
I am not
There is now a Wiki page that covers this topic, I welcome comments and corrections, this is my best understanding of the subject:
https://onstep.groups.io/g/main/wiki/Stepper-Motor-Accuracy
I am not
Hi Dave
Thanks for the info, really appreciate it. If I understand it correctly, the RJ45 connector is an 8 pin, and in this instance, bridged to essentially a 4 pin.
In terms of wiring, my stepper
Hi Dave
Thanks for the info, really appreciate it. If I understand it correctly, the RJ45 connector is an 8 pin, and in this instance, bridged to essentially a 4 pin.
In terms of wiring, my stepper
The sockets on the STM32 PCB are RJ45, with each pair of pins (1-2, 3-4, 5-6, 7-8) connected by the PCB. The interconnection is done to increase both current carrying capacity and robustness of the
The sockets on the STM32 PCB are RJ45, with each pair of pins (1-2, 3-4, 5-6, 7-8) connected by the PCB. The interconnection is done to increase both current carrying capacity and robustness of the
Vixen worm shaft extended on both sides and so, it may be broken only on one end. Since it is a Dec shaft you may still be able to use the mount. RA shaft damage may give you excessive PEC but Dec
Vixen worm shaft extended on both sides and so, it may be broken only on one end. Since it is a Dec shaft you may still be able to use the mount. RA shaft damage may give you excessive PEC but Dec
The motorizing of the mount is progressing, albeit slowly. The stepper motors have arrived (Nema 17 400 step, 0.9 degree, 0.9 A) and I have ordered the onstep STM32 unit. Am now want to sort out the
The motorizing of the mount is progressing, albeit slowly. The stepper motors have arrived (Nema 17 400 step, 0.9 degree, 0.9 A) and I have ordered the onstep STM32 unit. Am now want to sort out the
What is the quality like of a Bresser Mon2 eq Mount
I've seen a Vixen Great Polaris but the end of the declination worm gear shaft has sheared. This begs the question whether there is other damage to
What is the quality like of a Bresser Mon2 eq Mount
I've seen a Vixen Great Polaris but the end of the declination worm gear shaft has sheared. This begs the question whether there is other damage to
While I don’t own a CGE Mount, I wouldn’t exclude belt drive without some testing. You gain torque and by not using a gearbox, you reduce the likelihood of backlash, which can be significant
While I don’t own a CGE Mount, I wouldn’t exclude belt drive without some testing. You gain torque and by not using a gearbox, you reduce the likelihood of backlash, which can be significant
I am getting a CGE too with the purpose of converting it to Onstep.
I believe that belt drive provides better accuracy so I think that planetary gears would work for visual work, but for AP it is
I am getting a CGE too with the purpose of converting it to Onstep.
I believe that belt drive provides better accuracy so I think that planetary gears would work for visual work, but for AP it is
Do you mean ask it to slew to an RA/DEC combo, or tell it that it is pointing to a certain RA/DEC combo?
Both are possible, though I assume that you mean the latter, so you can polar align
Do you mean ask it to slew to an RA/DEC combo, or tell it that it is pointing to a certain RA/DEC combo?
Both are possible, though I assume that you mean the latter, so you can polar align
G'day,
I did a couple of things
- corrected an error in my StepsPerDegree (oops!)
- changed MaxAzm to 360
- reversed the direction of the Az motor
uploaded the code to the Teensy
And rebooted my phone
G'day,
I did a couple of things
- corrected an error in my StepsPerDegree (oops!)
- changed MaxAzm to 360
- reversed the direction of the Az motor
uploaded the code to the Teensy
And rebooted my phone
Now the LV8729 at 0.96A (40% power,) I will not test above this setting for this motor since the driver can't reach 1.7A My plan is to test at 40%, 70.7%, and 100% power where possible.
Now the LV8729 at 0.96A (40% power,) I will not test above this setting for this motor since the driver can't reach 1.7A My plan is to test at 40%, 70.7%, and 100% power where possible.
Is it possible to enter onstep scope Dec and RA coordinates manually?
I would like to point the scope to the zenith using a precision level for both Dec and RA; and set onstep azimuth to the current
Is it possible to enter onstep scope Dec and RA coordinates manually?
I would like to point the scope to the zenith using a precision level for both Dec and RA; and set onstep azimuth to the current
