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INDI Library v1.8.5 Released (19 Apr 2020)

April 2020 release of INDI Library v1.8.5 introduces new drivers while providing fixes and improvements to existing devices and core framework.

Mount park detection system - how?

5 months 3 weeks ago
universalmaster
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Mount park detection system - how? #46854
Hi!

I'm trying to automate the observatory and I think the roof is working ok now and it seems to work also with ekos weather system. Here I am using an all-sky camera to just count starts and report bad weather if I see too few stars. All seems ok. I'm using a RPI 3 for ekos and kstars, but hopefully I can move to RPI 4 when Ubuntu starts stabilizing.

Now, my problem is that I can only physically close the roof if the mount is truly in it's parked position, otherwise the roof will hit the scope. The parked position is with the telescope to the west and pointing slightly downwards. The mount is an old eq6 fitted with synscan upgrade and controlled using eqmod.

My fear is, that something goes wrong with the mount and it is not truly parked, e.g. because it have bumped into the pier instead.

Any good ideas on how to design a reliable sensor system that will tell me if the mount succeeded in parking or not? I'm not a sensor wizard, so no idea what to look for. Programming it will be no problem....

Best regards
Søren

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5 months 3 weeks ago
ChrisRowland
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Mount park detection system - how? #46864
Would it be possible to have a microswitch that will be operated by the OTA as it reaches the park position? You can get microswitches with long arms that are designed for this sort of thing, you may already have some on your roof.

The switch is connected to an input of your observatory safety system, the rest is just software.

Chris

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5 months 3 weeks ago
wotalota
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Mount park detection system - how? #46877
Another suggestion I've seen is a infrared transmitter and receiver or reflector, where the receiver is effective when the scope is in the parked position.
I wonder also about using an accelerometer something like learn.adafruit.com/adafruit-lis3dh-tripl...ter-breakout/arduino

Mach1, TS86SDQ, ASI071, ASI174, OAG, focusPro

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5 months 3 weeks ago
Ihoujin
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Mount park detection system - how? #46894
As Wotalota was suggesting, what you should look for is an electronic eye to sense when the mount it in a safe position.
Here is an example I've seen previously, although I'm not sure if the link will work because it is a Facebook group post.

www.facebook.com/1327031179/posts/102165...9/?sfnsn=mo&d=n&vh=i

It shows a mount being command to park in a safe position on command with an IR transceiver pointed to a retro reflector on the scope. Such a rig could probably be put together with an Arduino and garage door hardware.

INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.

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5 months 3 weeks ago
universalmaster
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Mount park detection system - how? #46903
Thanks a lot, I will look into the IR reflector things. It seems they way to go.

The movie worked fine and looked awesome :-)

I use reed switches for my roof, btw. They seem to function nicely for the roof, but I can not imagine how to connect them to sense if the scope is parked or not...

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3 months 2 weeks ago
Gonzothegreat
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Mount park detection system - how? #49699
I did find a long time ago a website selling parts for mounts, cannot find it again, but I did manage to find the model of the sensor:
uk.farnell.com/eaton-cutler-hammer/1451e...ic-sensor/dp/1771219
I thought about including it in my electrical circuit for the roof. Just an idea for you ^

Kstars Mac osx
Odroid C1 running indiserver (kept up-to-date with apt-get update/upgrade)
HEQ5 pro / QHY5L-II-M (OAG) / Atik 314L+ / Gerd Neumann drawer

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3 months 1 week ago
wildi
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Mount park detection system - how? #49983
Hello Søren

having my mount and telescope seen more than once in this position:


I was looking for an solution too. I used two acceleration sensors, a bit of math and the assumption, that the hour axis is aligned (including C++ source) to get the absolute orientation in space. The accuracy is about +/- 0.2 degrees.

Lately I stumbled over a more recent product: Adafruit 9-DOF Absolute Orientation IMU Fusion Breakout - BNO055 .

Kind regards, wildi

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3 months 1 week ago 3 months 1 week ago by Gonzothegreat.
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Mount park detection system - how? #49984

ChrisRowland wrote: Would it be possible to have a microswitch that will be operated by the OTA as it reaches the park position? You can get microswitches with long arms that are designed for this sort of thing, you may already have some on your roof.

The switch is connected to an input of your observatory safety system, the rest is just software.

Chris


I use this kind of limit switch to check if my roof is closed or opened.


In fact, I do have a couple of spare ones, I think I'll add one to be sure the scope is 100% parked.
If you do go down that route, do not get a micro switche, I used them before and they do fail as they are fragile. Get that heavy duty like in the picture above there.

Kstars Mac osx
Odroid C1 running indiserver (kept up-to-date with apt-get update/upgrade)
HEQ5 pro / QHY5L-II-M (OAG) / Atik 314L+ / Gerd Neumann drawer
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