Telescope Dome Sensors

Web-accessible floor sensors are used to report the conditions inside the Yerkes telescope domes. Data from these sensors are logged by the Stars Server and graphs shared online.

Sensor Pages

The 24" Sensor box is at 128.135.40.55 and it's data page is under stars.uchicago.edu/telescopes/yerkes24/Yerkes24Env.html.

The 41" Sensor box is at 128.135.40.65 and it's data page is under stars.uchicago.edu/telescopes/yerkes41/Yerkes41Env.html.

The Display Sensor box is at 128.135.40.87 and it's data page is under stars.uchicago.edu/telescopes/yerkesDisplay/YerkesDisplayEnv.html.

Task / Fixes List

• At the beginning of the month the plots don't get updated for a week (probably crash when 2 months are involved). Needs fixing.

Hardware

Sensors:

• Distance sensor: MaxBotix Ultrasonic RangeFinder EZ3. Has a narrow beam to reduce noise and avoid thin objects. Measures distance to ground from elevated floor.
• Light sensor: Plastic coated photoresistor. Measures light in dome.
• Humidity/ Temperature sensor: DHT-22 / RHT03. Digital readout via one pin and pulses. Measures humidity and temperature in the dome.
• Contact pushbutton: Big red pushbutton attached to a wooden puck and big washers as weights. It's attached to a telephone wire in order to hang further away from the board. Used to confirm that the floor is down, and it activates a buzzer to warn people in the dome of this event.

Readout Mediums:

• LCD Display: From the Hacktronics site. 16x2 display size.
• Website: 128.135.40.55 (See above for link)

The electrical schematics can be found under WHERE ARE THEY??? ARE PDF's AVAILABLE?

Software

The arduino programs for the sensor boxes are in the folder /stars/StudentGroups/tech/Floor_Sensor *use files named "DTHLsensor24/41_v1.ino"

The basic idea of the program is that it collects data from the environment to detect the temperature, humidity, and luminosity. In the main loop, the program goes through the following tasks:

• Converts the ping values from the distance sensor into inches and centimeters.
• Converts the resistance values from the photo-resistor into luminosity.
• Converts values read by the DHT sensor into temperature (Fahrenheit and Celsius) and humidity (percentages).
• Creates the dome sensor websites and prints the data collected by the sensors.

The arduino program serves two pages, the normal page under / and a page with just the data under /raw/ (for example 128.135.40.55/raw/).

The server programs are on the stars server in the /data/scripts/black_box folder. The following programs are used to collect the data:

• yerkes24/41/Displayenv.sh (shell script one for each sensor box):
  • This is the script which has to be called once a minute.
  • The script runs DTHLServerData.py and DTHLServerGraph.py (see below).
  • Copies the whole .html code from the sensor graph pages to /data/filemanager/Research/Telescopes/yerkes24(or)41 -and- /var/www/html/telescopes/yerkes24(or)41
  • Copies the collected data from logs/DataLogs/*_DataLog24(or)41.txt to /data/filemanager/Research/Telescopes/yerkes24(or)41 -and- /data/public/DataLogs
• scripts/DTHLServerData.py: A python script that grabs the data collected by the floor sensor and logs it into a text file (located at logs/DataLogs/*_DataLog24(or)41.txt). It is called by yerkes24/41env.sh
• scripts/DTHLServerGraph.py: A python script that combines the collected data from logs/DataLogs with the graph template file and outputs it as a new file in logs/Yerkes24/41Env.html .

The data is in the /logs/DataLogs folder and copied to stars.uchicago.edu/public/DataLogs and stars/Research/Telescope/yerkes41 on the filemanager. The format of the data files is: Date, Floor Height (inches), Luminosity (Lux), Temperature (C), Humidity (%). Other files used by the program are

• scripts/GraphTemplate24/41.html: Skeleton file that the Yerkes24/41Env.html files read and turn into graphs.

All software files are located on the Filemanager server under stars/StudentGroups/tech/Floor_Sensor.

Yerkes 41 Inch Sensor

The telescope log with graphs is available under stars.uchicago.edu/telescopes/yerkes41/Yerkes41Env.html.

Description:

The purpose of this sensor is to monitor whether or not the floor is down, the distance from the elevated floor to the ground, and whether or not either match. It also serves to monitor light levels, the temperature, and the humidity inside the dome. This information can be checked on an LCD display inside the dome and on the internet. The website (found at 128.135.40.55) is designed to ease the remote use of the telescope and inform the user of the condition inside the dome. The LCD display (found in the dome) is used for the same purpose, except that it is used by people inside the dome rather than outside of it. A secondary purpose for it is to provide data for the collection of graphs in order to find trends in the data. A tertiary and minor purpose for this sensor is to tell the in-dome operator whether or not the floor has reached its lower limit via a buzzer.

Stone Edge Sensor

Contact:

• Richard Treffers: RichardTreffers@StarmanSystems.com

Requirements:

• Light, Temperature, Humidity Sensor for Stone Edge

Setup:

• IP and Internet: Will be behind a secure firewall - need to tunnel to get access from the outside.
• Power supply: 110V is available
• The image right shows the wall where the sensors will be
• No LCD display as space is limited and there are rarely people in the dome.

To do:

• Package Requirements:
  • IP provided. Local IP to tunnel through: 10.0.0.210 [_]
  • 9v of power okay. Omit external power supply w/ jack. [_]
  • Waiting on pins from Digikey. [_]
  • Attach Arduino at bottom via non-conductive spacers, solder wires to female pin headers, attach sensors. [_]
  • Vents with 1 inch diameter okay. Optimize space? [_]
  • Send to StoneEdge to fix possible tunnel /DoA issues. [_]

Display Case Sensor

The sensor located in the high school group's display case is very similar to the telescope dome sensors, except that it is in a "prototype" form rather than placed in a box. It is meant to be interactive for people who are visiting or touring Yerkes, so it is set up so that guests can cause the sensor readings to change and see the values on the LCD display. We kept it in a prototype form so that visitors would be able to see all of the various hardware and wiring that is involved as well. The display case sign is attached at the bottom of this page. The sensor's IP address should be 128.135.40.87.

Remote board wiring details:

• Red wire: Raw(main arduino), five volt(distance), and VDD power supply(humidity)
• Black wire: Ground for both
• Blue wire: PW (on distance sensor)
• White wire: A1(main arduino), data signal ( humidity sensor)

Possible improvements:

• Design a small encasement for the distance and temperature/humidity sensors (these two will be outside of the display case, placed on top of it)
• Design a device (e.g. tubing or something similar) that will make it easier for people to change the humidity readings with their breath
• Find a way to make the sensor more accessible to guests who are blind, possibly something related to visiting the sensor's website on their phones