Add Weather 1 as a Choice for Refraction Corrections in Antenna

Modification Request #4 (C3 2006)

1. Introduction

We plan to install a humidity/temperature instrument at Weather 1, giving us full redundancy with Weather 2. Jason Ray has the instruments in hand, and will supervise the installation.

Advantages: Complete redundancy for refraction corrections and weather conditions. It allows us to take WT2 down for calibration or repair without impacting high-frequency observations. Currently there are no spare fibers to WT2; installation of a six-fiber cable will allow the radio repeater installation as originally planned plus provide spare fibers, but the station will be out of service for a couple of days to do so.

This MR specifies the software changes necessary to make Weather1 a selectable choice in the Antenna Manager for refraction corrections. This MR complements the work being done in ModificationRequest3C306.

2. Background

The mechanism by which the antenna obtains weather information is as follows:

The Weather managers collect raw weather data and publish it via the ygor monitor/sampler system
The getWeather daemon collects this information and performs a moving average on the data
The antenna queries the getWeather daemon via http (getWeather provides a mini-webserver)

The weather source for the antenna is controlled by the "WeatherStation" entry in the antenna.conf configuration file.

Currently the antenna only understands information from weather2, because weather1 does not provide sufficient information for refraction calculations. The response format for all weather stations will be standardized to a common format. Weather stations which do not contain sensor's for a particular item will indicate "N/A".

3. Requirements

Make the weather measurements from Weather1 a selectable choice in the Antenna Manager for refraction corrections.

4. Design

This MR will require changes to the output formats on the mini-webserver 'getWeather', to return information in a unified common format. The intent is to define a easily parsed format to be used for all weather stations regardless of instrumentation. The weatherMonitor class used by the antenna to parse the information will be slightly modified to understand the newer format and to improve error checking.

4.1 GetWeather Daemon Changes

The returned data format for all weather stations will be normalized to the example provided below. If an instrument or value is unavailable, the field value will be marked "N/A".

An example of the new format for all weather stations:

4/18/2006 14:3:43
MJD: 53843
Sec: 50623.020000
WindVel:    0.64
WindDir:  301.02
Temp:    5.59
Press:  922.39
Dewpoint:    4.89
Humidity:   N/A
Lightning:  0
MaxWind:    0.66
Histogram: 60 0 0 0 0 0 0 0 0 0 0

4.2 Antenna Changes

The antenna weatherSource parameter will be modified to provide the choices "Weather_Station_1, Weather_Station_2, or UserInput". The host for the weather server will be controlled by the WeatherHost entry in the system.conf file.

5. Deployment Checklist

What has to get done to integrate this completely into the system. This checklist must be completed before Cycle Integration Testing begins.

ModificationRequest3C306 must be complete in order to deploy.
Training: Operators, Jason Ray, and JD Nelson need to know how to select which weather station is used for refraction in case the active station fails.
Include a description of these changes in the release notes.
Communication with Computing group needed? No.
What documentation needs to be updated? Add procedures for changing weather station selection.
Training Needed? Is this being released to staff astronomers or everyone right now? Full release.
Notification Needed?
- Inform Chris Clark of the data format change, as he has applications which use the data.

6. Test Plan

Confirm that refraction calculations are correct when WT1 is selected, and that they are still correct when WT2 is selected. Should be checked at 2-3 elevations.

Signatures

APPROVED: I acknowledge that my request is fully contained in this MR, and if the SDD delivers exactly what I specified, I will be happy.

ACCEPTED: I acknowledge that I have validated the completed code according to the acceptance tests, and I am happy with the results.

Written	- JoeBrandt - 20 Apr 2006
Checked	- AmyShelton - 25 Apr 2006
Approved by Sponsor	- RonMaddalena - 26 Apr 2006
Approved by CCC	- RonMaddalena - 11 May 2006
Accepted/Delivered by Sponsor	- RonMaddalena - 11 May 2006

Symbols:

Use %X% if MR is not complete (will display )
Use %Y% if MR iscomplete (will display )

CCC Discussion Area

In our discussions, we wanted to confirm that the source of the weather data was written to a fits file somewhere so that the observer would know the source of the weather data. Is that done?

Topic ModificationRequest4C306 . { Edit | Attach | Ref-By | Printable | Diffs | r1.11 | > | r1.10 | > | r1.9 | More }

Revision r1.11 - 11 May 2006 - 14:22 GMT - RonMaddalena Parents: PlanOfRecordC32006	Content copyright © 1999-2007 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.


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