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--- iothings:proiecte:2022:razvanandreistoica [2023/01/20 01:15]
razvan.stoica0211
+++ iothings:proiecte:2022:razvanandreistoica [2023/01/20 03:01] (current)
razvan.stoica0211 [2. Hardware]
@@ Line 20: / Line 20: @@
 ===== 2. Hardware =====
 === Mechanical Elements ===
-  * The largest part of the project is the chassis. This allows the movement of an antenna on two axis and also hosts all the electronics.
+  * The largest part of the project is the chassis. This allows the movement of an antenna on two axis and also hosts all the electronics. It uses 4 radial bearings and one axial bearing. Everything (except for the bearings, axes and screws) was 3D printed with PETG.
 {{:iothings:proiecte:2022:fusion_-_copy.png?300|}}
   * The antenna is one of the most important parts of this project. I chose to go with the default antenna that came with the RTL-SDR Kit. It is a V-Dipole adjustable one. In order to make this project work, I had to adapt it and print a piece that keep the two poles at a 120 degree angle. According to an article from the RTL-SDR forum, each pole's size must be 53.4cm.
 {{:iothings:proiecte:2022:adams_v-dipole-500x375.png?300|}}
+  * A dedicated ground plane had to be built for the GPS antenna. It is a 70x70mm PCB with a hole where the cable of the antenna passes.
@@ Line 295: / Line 297: @@
 === Firebase ===
+== Code and Configuration ==
 The database has been configured the same way it was done at school, but the field in the database are rather rewritten than appended.
 A firebase-hosted web app has also been added as the GUI for the project (again, same as at school). It uses a simple html page and the following javascript code that deals with database communication:
@@ Line 363: / Line 366: @@
 </code>
-===== 4. References =====
+== GUI ==
+The GUI can be seen in the picture below. The web app outputs antenna's current position, the longitude and latitude of the device and the RPi's IP and expects one of the two buttons pressed as input (those will move the antenna on one of the axis).
+The address of the web app is: https://noaa-tracker.web.app/
+{{:iothings:proiecte:2022:gui.png?900|}}
+===== 4. Using the Device =====
+In order to use the device, one should follow those steps:
+  - Connect the Raspberry Pi to the LAN via Wi-Fi or Ethernet (the later might not be possible do to the rotating nature of the device);
+  - Install SDR#, GPredict, SDRSharp.GpredictConnector, WXtoIMG and VBAudio Cable (Internal Audio Routing);
+  - Start SDR#
+  - Select //RTL-SDR TCP// as source -> Click on Gear Icon -> Add the IP address of the RPi (that can be seen in the GUI) in the IP field;
+  - Select Settings (3 lines) -> go to Plugins -> GPredictConnect -> Check the //enable// checkbox;
+  - Select Settings (3 lines) -> go to Audio -> click on Output -> Select //[Windows DirectSound] Cable Input (VB-Audio Cable)//
+  - Select Settings (3 lines) -> go to Radio -> check //WFM// radio button (how funny) and set the Bandwidth to 40KHz
+  - Start GPredict
+  - Go to Edit -> Preferences -> Ground Station and add a new ground station using the information from the GUI (latitude and longitude)
+  - Go to Edit -> Preferences -> Interfaces -> Add new Interface (SDRSharp with default port)
+  - Go to Edit -> Update TLE data from network
+  - Go to Edit -> Update transponder data
+  - Go to File -> New module -> choose a name; choose your ground station name; choose the 3 NOAA satellites (15 18 and 19) and add them to the right -> Click OK
+  - Go to the little triangle to the right (Module options / shortcuts) -> Radio Control -> Select your Radio defined earlier and click Engage
+  - From the Radio Control panel -> Choose a satellite that's in your range -> Choose APT Downlink -> Click Track and T buttons
+  - Go to the little triangle and also check the "Autotrack" checkbox
+  - Open WXtoImg
+  - Go to Options -> Ground Station Location -> Set latitude and longitude -> Click Ok
+  - Go to Options -> Recording Options -> Make sure the soundcard is the VB-Audio Virtual Cable -> Click Ok
+  - Go to File -> Update Keplers (deprecated, must find another way)
+  - Go to File -> Record -> Auto Record
+  - Wait & Hope
+But how does it work?
+  * The SDR#, is, as the name says, a Software Defined Radio. It is used to receive and filter radio waves. This tool uses RTL_TCP as a device (the RTL_SDR connected to the RPi.
+  * GPredict is a software that tracks satellites and predicts their future positions. This tool will adjust the frequency to the desired satellite (closest one when auto-tracking).
+  * WXtoImg takes the analogic data and converts it into images. This software receives the data from SDR# via a virtual "audio cable".
+===== 5. Challenges =====
+Here is a list of past and current problems
+  * Many plastic parts had to be redone multiple times and some still do
+  * The design is really bad
+  * The device needs a power supply
+  * The device needs a way to receive current without cables (maybe brushes or batteries)
+  * The device has 3 antennas near 2 big motors, what could go wrong
+  * RTL-SDR is getting hot, please don't burn
+  * GPS doesn't work indoors (mostly works near windows)
+  * The main antenna is not optimal
+  * The IMU loses its calibration quickly, doesn't have an EPROM and is very hard to calibrate
+  * The IMU doesn't even reach 90 degrees when vertical, for some reason
+===== 6. References and Links =====
   * https://www.noaa.gov/
   * https://www.ngs.noaa.gov/AERO/Genspecs_A/Volume%20A_Attachment%2011-19.pdf
-  * https://www.youtube.com/watch?v=tdGatHMi350
+  * https://www.youtube.com/watch?v=qrcWeYoTGaw
-  * https://www.youtube.com/watch?v=bYpTsersKX8&t=1s
+  * https://www.youtube.com/watch?v=bYpTsersKX8
+  * www.airspy.com
+  * www.gpredict.oz9aec.net
+  * www.wxtoimgrestored.xyz
+  * www.vb-audio.com/Cable
+  * https://usradioguy.com/wxtoimg-kepler-fix/