Mount Park Sensor

Description

Mount Park Sensor

Roll off roofs have one major drawback when compared to domes for the housing of large telescopes. The interference fit. An interference fit is when a telescope can protrude above the plane of a roll off roof path of movement requiring a telescope to be below that plane for the roof to close and to not impact the telescope during that operation.  It has been common practice for standard Infrared sensors to be used as verification that a telescope is properly parked. An emitter/receiver can be pointed at a scope in the proper safe position and a reflector mounted on the scope to reflect that light allowing the circuit to close confirming a safe condition. 

 

Dark Dragons uses light emitting sensors for safety pinch point locations to keep people safe from a roof that could close on them and also for the telescope park position. In practice some customers have found calibrating those light emitter sensors for park position difficult and we agree, they are not ideal.  Furthermore, after additional research we found the frequency that common sensors emit is in the same bandwidth that Hydrogen Alpha sits. This was a game changer for us as we have purposefully designed our equipment to NOT emit any light. Even our ethernet LEDs will black out after confirming your network is working. 

 

We found a better solution to your park position verification, the Mount Park Sensor. The MPS is a simple, tiny device custom designed to attach to your telescope. With its on board accelerometer, and the core Dragon Firmware, the MPS can talk directly to your DragonLAIR Roof controller and will show your system as Safe or Unsafe and allow the roof to operate only when you want it to. We also added a bit of our ASCOM Alpaca hardware magic to allow the MPS to act as an ASCOM switch. So those that want to include the scope park position into custom scripts, add functionality to a software application, or require extra status of an array of scopes housed under one roof, now can easily do just that with one device the size of a 3” Vixen dovetail. 

 

The MPS uses a standard accelerometer on board to constantly report roll and pitch to your local network. It is a standalone device requiring no PC connection and is powered by a single USB cable. Using the devices built in web page users can connect directly to the MPS and with a simple click, set and save the scope park position. And when you rearrange your rig and move the placement of the sensor, recalibration will take less then 30 seconds to log in and set the new park position. Custom naming conventions allow you to use a common name for scope identification.

 

The DragonLAIR Roof controller will automatically detect the device when it appears on the same network and allows you to activate or deactivate its use. An error adjustment allows you to set the max amount of error to the pitch and roll to ensure your scope can be just below the roof before being marked as safe.

 

And with its WiFi connection to your observatory’s network, there are no more H-alpha similar light being broadcast at your optics. 

 

In order to keep the cost down we are currently only able to use 3D printed plastic housing for the sensor. If you are a DIY maker and want to incorporate the sensor into one of your own designs, we are happy to share the STEP files that will give you the size and orientation of the PCB for your own use. And if you’d like to share your idea, our forum has a section dedicated to these types of projects. We support open source. Future ideas include aluminum dovetail bars with the sensor hidden inside, but that is some time away. 

 

If you have any questions feel free to let us know and we will be happy to help.