At-field- Pre-Flight Checklist

  1.3. Preflight Checklist – At field before arming 
      
      1.3.1 Camera settings (Based on Canon PowerShot S100/S95/S110 Point & Shoot cameras)
            
            → General recommendations for aerial imagery:
            
             ❏ Keep the camera focal length fixed throughput the mission.
             ❏ Shoot in RAW since the RAW format retains maximum scene details and provides greater flexibility during post-processing. 
             ❏ Use faster shutter speeds to avoid blur due to vehicle speed and vibration.  
             ❏ Use gimbal to get maximum nadir shots of the scene and to avoid image blurring.
               
            → Choose one of the following camera shooting parameters:
            
              1. Shutter Priority (Tv) mode: 
                 
                 ❏  In Tv mode, only shutter speed needs to be adjusted, ISO and F-number are automatically adjusted by camera based on scene conditions.
                 ❏  Shutter speed: fastest or close to fastest (for S100 canon, 1/1250, 1/1600, or 1/2000 would work, depending upon the light conditions). Tip:
                    faster shutters less light hitting the sensor. 
                 ❏  Optional: Ev (exposure): 0, -1/3 or -2/3 (again adjust based on ambient light conditions)
             
              2. Manual (M) mode:
               
                 ❏  Shutter speed: fastest or close to fastest (for S100 canon, 1/1600 or 1/2000 would work, depending upon the UAV speed and weather conditions)
                 ❏  ISO: ~80-250 (adjust based on ambient light). Hint: Higher ISO, brighter image but higher noise.
                 ❏  Aperture (f-number): 4.0-5.6. Note: Small f-number means wider apertures and shallow depth of field. In our experience, F-number of 4-5.6 is 
                    a sweet spot. It is recommended that you play around with the manual settings to setup your camera to suit your specific requirements. 
                 ❏  Ev (exposure): -1/3 or -2/3. Again, adjust based on ambient light conditions.
                 ❏  Additional note: Use the vertical bar with moving pointer to adjust the camera settings to get proper exposure (not too bright and dark). The 
                    pointer should point at or below the mid-mark. 
                  
            →  Set the Manual Focus (MF) setting to infinity for above 5 meter altitude flights. 
            →  Image recording format: Camera raw (CR2)
            →  Under MENU option, make sure:
                   ❏  GPS ON 
                   ❏  MF-point ZOOM OFF
                   ❏  Safety MF OFF
                   ❏  Wind Filter OFF
             
            → Some general recommendations for aerial imagery:
                   
                   ❏  Keep the camera focal length fixed throughput the mission. 
                   ❏  Shoot in RAW since the RAW format retains maximum scene details and provides greater flexibility during post-processing. 
                   ❏  Use faster shutter speeds to avoid blur due to vehicle speed and vibration.   
                   ❏  Use gimbal to get maximum nadir shots of the scene and to avoid image blurring.

      1.3.2 UAS In-field Pre-flight
         
         ❏  Place the UAV on a flat surface, plug-in the battery and close the lid. 
            Note: Avoid any disturbance to the UAV during initial few seconds as the UAV performs automatic sensor-calibrations. 

❏ Lock the SD card and insert it in camera. ❏ Switch-on the camera by pressing the preview button.Half-press the shutter to let the lens out. ❏ Set the camera parameters by following the instructions given in section 1.3.1. ❏ Attach the camera to the gimbal mount and plug-in the wire. ❏ Load and run CHDK script by half-pressing the camera shutter button. ❏ Open mission planner on field laptop and connect mission planner to UAV Autopilot using telemetry radio link. Use a correct COM PORT Number and 57600 Baud rate from the drop down menu on top right corner of mission planner software. Then hit connect. ❏ Check flight parameters (see parameter section below for detailed parameter list) ❏ Load proper mission waypoint file and write the waypoints into the Autopilot through radio link. Note: You can read back the WP from UAV to double check the correct WayPoints are written to the UAV. ❏ Make sure the GPS signal is good (3D fix: number of satellites > 7 and hdop < 2) and there is no error message flashing on the mission planner main window. ❏ Check if the camera trigger is working properly by walking the UAV. Note: Make sure the UAV safety light is flashing to avoid accidental arming. ❏ Check battery voltage. ❏ Turn the radio controller (RC) transmitter on. ❏ Check to make sure the RC switch positions are set to: ❏ Stabilized Mode [ON], RTL [OFF], Throttle [All the way Down]. ❏ Depending upon how the other RC switches are mapped, make sure the switches are set to a mode that is safe for take-off. ❏ Check the trims are zero (offsets to stick positions that can be set with small slide switches). ❏ Make sure no one is close to UAV and survey area.