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L42ARO edited this page Mar 15, 2024 · 7 revisions

A typical LORA string would look like this:

+RCV=<sender address>,<length>,<data>,<rssi>,<snr>

As it can be seen it already contains overhead data that details who is sending it, therefore for our commands standard we will skip specifying who is the sender in the <data> field.

Shared Patterns

  • Every module will send AWAKE on startup
  • If a PING is received every module should send back a PONG this will be used to check if the module's LoRa is active
  • For non handled cases every module should send back INVALID:<string> where the <string> portion is the unhandled case sent
  • Most commands should specify with a short prefix which group their action falls under so that the response can label itself under that action. Ex: an altitude request should have a prefix of ALT:, so that the response can say ALT:<value>.
  • Commands that are too important like ABORT, or PING do not need to be preceded by anything since it's important for the program to interpret them easily and fast
  • Certain commands that trigger actions inside the modules that may not lead to immediate feedback (Ex: GPS:SINGLE cannot send back GPS data until the GPS gets a Fix). These commands should send back the same command they received with +RCV as a postfix. This helps us ensure commands are being received.

    Ex:

    sequenceDiagram
participant R as Recovery Module
participant G as Ground Station
G->>R: GPS:SINGLE
   activate R
   R->>G: GPS:SINGLE+RCV
   note right of R: Then it can wait for a GPS FIX
    Loading

Summary

sequenceDiagram
    participant P as Payload Module<br>(Drone)
    participant D as Deployment Module
    participant G as Ground Station
    participant R as Recovery Module
    rect rgb(100,100,100)
    note right of P: Modules Startup
    R->>G: AWAKE
    D->>G: AWAKE
    P->>G: AWAKE
    end
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sequenceDiagram
participant P as Payload Module<br>(Drone)
    participant G as Ground Station
    rect rgb(50,100,155)
      note right of P: PAYLOAD
      G->>+P: PING
      P->>-G: PONG

      G->>+P:ABORT
      P->>-G:ABORT+RCV

      G->>+P: JETTISON:LCK
      P->>-G: JETTISON:LCK+RCV
      G->>+P: JETTISON:TRIGGER
      P->>-G: JETTISON:TRIGGER+RCV
      
      G->>+P:STEMNAUT:SINGLE
      P->>-G:STEMNAUT:<ARRAY<<br><accel ARRAY<INT>>,<gyro ARRAY<INT>>,<temp INT>,<sound INT>,<pressure INT><br>>>
      G->>P:STEMNAUT:REPEAT
      activate P
      P->>G:STEMNAUT:REPEAT+RCV
      loop every 1 second
        P->>G:STEMNAUT:<ARRAY<<br><accel ARRAY<INT>>,<gyro ARRAY<INT>>,<temp INT>,<sound INT>,<pressure INT><br>>>
      end
      deactivate P
      G->>+P:HEALTH
      P->>-G:HEALTH:<br><bmp status BIT>,<bno status BIT>,<mic status BIT>,<flight controller connection status BIT>

    G->>P: GPS:SINGLE
    activate P
    P->>G: GPS:SINGLE+RCV
    alt GPS Fix
    P->>G: GPS:<NMEA STRING Val>
    else No Fix
    P->>G: GPS:FAIL
    end
    deactivate P
    G->>P: GPS:REPEAT
    activate P
    P->>G: GPS:REPEAT+RCV
    loop Every 1 second
    alt GPS Fix
    P->>G: GPS:<NMEA STRING Val>
    else GPS No Fix
    P->>G: GPS:FAIL
    end
    deactivate P
    end
      G->>+P: <NON HANDLED CASE>
      P->>-G: INVALID:<STRING>
    end
Loading 
sequenceDiagram
participant D as Deployment Module
    participant G as Ground Station
    rect rgb(100,150,100)
      note right of D: DEPLOYMENT
      G->>D: PING
      activate D
      D->>G: PONG
      deactivate D
      G->>+D: ALT
      D->>-G: ALT:<INT>
      G->>+D: DPLY:DEPLOY
      D->>-G: DPLY:DEPLOY+RCV
      G->>+D: DPLY:STATUS
      D->>-G: DPLY:STATUS+<STRING>
      G->>+D: DPLY:STOP
      D->>-G: DPLY:STOP+RCV
      G->>+D: DPLY:RESET
      D->>-G: DPLY:RESET+RCV
      G->>+D: DPLY:RETRACT
      D->>-G: DPLY:RETRACT+RCV
      G->>+D: DIST
      D->>-G: DIST:<INT>
      G->>D: TRSH:SET+<INT>
      activate D
      alt Succesfully set threshold
      D->>G: TRSH:SET+YES
      else Set failed
      D->G: TRSH:SET+FAIL
      end
      deactivate D
      G->>+D: TRSH:GET
      D->>-G: TRSH:SET+<INT>
      
      G->>+D:HEALTH
      D->>-G:HEALTH:<bmp status BIT>,<dist sensor status BIT>
      
      G->>+D: SENSE:SINGLE
      D->>-G: SENSE:<altitude INT>,<distance INT>,<status STRING>
      G->>D: SENSE:REPEAT
      activate D
      D->>G: SENSE:REPEAT+RCV
      loop Every 1 second
        D->>G: SENSE:<altitude INT>,<distance INT>,<status STRING>
      end
      deactivate D

      G->>+D: <NON HANDLED CASE>
      D->>-G: INVALID:<STRING>
    end
Loading 
sequenceDiagram
participant G as Ground Station
    participant R as Recovery Module
    rect rgb(100, 80, 155)
    note right of G: RECOVERY
    G->>R: PING
    activate R
    R->>G: PONG
    deactivate R
    G->>R: GPS:SINGLE
    activate R
    R->>G: GPS:SINGLE+RCV
    alt GPS Fix
    R->>G: GPS:<NMEA STRING Val>
    else No Fix
    R->>G: GPS:FAIL
    end
    deactivate R
    G->>R: GPS:REPEAT
    activate R
    R->>G: GPS:REPEAT+RCV

    loop Every 1 second
    alt GPS Fix
    R->>G: GPS:<NMEA STRING Val>
    else GPS No Fix
    R->>G: GPS:FAIL
    end
    end
    deactivate R
    G->>+R: <NON HANDLED CASE>
    R->>-G: INVALID:<STRING>
    end
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Sample GPS NEMA: A,2803.9766,000,08225.0083,W

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