FIELD OF VIEW GeoSnap Pro User Manual

GeoSnap Pro

User Manual

2 2 2

Date

Revision

3/17/14

Manual created

4/1/14

Added VN-200 INS state error code table

4/3/14

Added GPS antenna installation instructions

5/26/14

Added Garmin trigger mode description

9/26/14

Updated voltage range

9/26/14

Added instructions for using a new microSD card

2/19/15

Updated CONFIG file section to include new image file names

6/8/15

Adjusted GeoSnap Pro naming convention

12/14/15

Added Troubleshooting section

2/11/16

Updated to match 2.3.x firmware

3/28/16

Added File synchronization procedure

5/23/16

Updated to match 2.4.x firmware

6/29/16

Updated

7/18/17

Added camera cycle time section

11/30/17

Clarified antenna offset

8/17/18

Updated and reworked entire manual

3 3

CONTENTS

OVERVIEW ............................................................................................................................4

GeoSnap Pro Components ..................................................................................................4

Control Unit................................................................................................................................................... 4

Hotshoe Module ........................................................................................................................................... 4

Accessories .................................................................................................................................................... 4

GETTING STARTED................................................................................................................5

Installing the GeoSnap Pro on a DSLR-style Camera .............................................................5

Mounting the GPS Antenna ......................................................................................................................... 6

Pigtail Trigger Cable ...................................................................................................................................... 6

Using the GeoSnap Pro .......................................................................................................7

GeoSnap Files................................................................................................................................................ 7

Synchronizing Image Names ........................................................................................................................ 9

Configuring for Mapping Flights .................................................................................................................. 9

Powering On the GeoSnap ........................................................................................................................... 9

LED Codes .................................................................................................................................................... 10

CONFIGURATION FILE ........................................................................................................11

AUXILIARY I/O CONNECTIONS ...........................................................................................24

External Trigger Input ....................................................................................................... 24

UPDATING FIRMWARE .......................................................................................................25

OPERATIONS CHECKLIST ....................................................................................................26

CAMERA SETTINGS .............................................................................................................27

Required and Recommended Settings ............................................................................... 27

Image numbering ............................................................................................................. 28

Camera cycle time considerations ..................................................................................... 28

TROUBLESHOOTING ...........................................................................................................30

GPS signal quality test ...................................................................................................... 30

Basic test ..................................................................................................................................................... 30

Identification test ....................................................................................................................................... 31

INS_stat code lookup tables.............................................................................................. 32

SPECIFICATIONS .................................................................................................................33

Physical specifications ...................................................................................................... 33

Power specifications......................................................................................................... 34

MicroSD card specifications .............................................................................................. 34

4 4 4

OVERVIEW

GeoSnap Pro Components

The Field of View GeoSnap Pro was developed to streamline DSLR-style camera payload integration, facilitate intelligent triggering, and produce a valuable log of position/attitude conditions at the moment of image capture.

CONTROL UNIT

HOTSHOE MODULE

ACCESSORIES

Power input

MicroSD card slot

Onboard button

Auxiliary I/O port

Wired trigger port

Control unit port

IR LED port

GPS antenna port

5 5

GETTING STARTED

Installing the GeoSnap Pro on a DSLR-style Camera

Slide the hotshoe module onto the hotshoe of the camera and twist the lock ring clockwise to tighten down the lock.

Pull back on the GPS antenna strain relief and swivel the GPS antenna cable into place.

Plug the GPS antenna’s MMCX

connector into the antenna port on the VN-200 (press until it clicks into place).

Plug the trigger cable into the hotshoe module and the camera trigger port.

6 6

MOUNTING THE GPS ANTENNA

Make sure you mount the GPS antenna with the top facing up and with a clear view of the sky. Also make sure that you do not mount the antenna near transmitters on the aircraft that could cause interference and degrade the performance of the GPS.

Ground plane (optional)

To improve your GPS accuracy, it is recommended that you place a 10 cm diameter round or 10 cm x 10 cm square ground plane under the GPS antenna. This could be as simple as placing some aluminum tape (that you can buy from a hardware store) around a piece of wood or cardboard, sticking the antenna to the center of the plate, and attaching that whole assembly to the top of your aircraft.

PIGTAIL TRIGGER CABLE

If you are not using a camera with a Sony multiport trigger connection, you will have been provided with a 3-wire (green, white, black) pigtail trigger cable. When the GeoSnap system sends a trigger command to the camera, it simply shorts the focus (white) and shutter release (green) lines to ground (black). To make a trigger cable for your camera with this pigtail it is recommended that you follow these steps:

1. Purchase a stock wired remote for your particular camera model.

2. Cut the stock remote cable 1-5” from the connector depending on the location of the

wired remote port relative to the GeoSnap hotshoe module.

3. Strip the ends of the stock remote cable wires.

4. Identify which cables in the stock cable relate to Ground, Focus, and Shutter Release.

5. Connect the wires to the provided pigtail trigger cable as follows: Ground -> Black, Focus

-> White, and Shutter Release -> Green.

6. Plug the cable into the camera and the GeoSnap hotshoe module as shown in steps 6

and 7 of the GeoSnap installation procedure above.

TOP

7 7

Using the GeoSnap Pro

GEOSNAP FILES

There are various text files stored and/or logged on the microSD card. These files, and their purposes, are described in this section.

Configuration File (CONFIG.txt)

The CONFIG file is where you can adjust all of the settings of the GeoSnap. Each time the GeoSnap is powered, it searches for the configuration file and reads the settings. If this file is not present, the GeoSnap creates a new configuration file with default options. For full descriptions of all the settings in the CONFIG file, see the Configuration File section of this manual.

Image Log File (001-IMG.txt)

The IMG log file is a log of the image name and position/attitude of the camera at the moment of image capture. Information is logged as plain, ASCII text in space-separated columns; each column is 14 characters wide.

Image Log File Columns

Label

Units

Description

image

name

Image name/counter

gpsdate

YYYY-MM-DD

Date as reported by the VN-200

gpstime

HH:MM:SS.SSS

Time as reported by the VN-200

lat(deg)

degrees

Latitude as reported by the VN-200

lon(deg)

degrees

Longitude as reported by the VN-200

hght(wgs84-m)

meters

Height above WGS84 ellipsoid

roll(deg)

degrees

Roll as reported by the VN-200 (positive roll is a roll to the right)

pitch(deg)

degrees

Pitch as reported by the VN-200 (positive pitch is a pitch up)

yaw(deg)

degrees

Yaw as reported by the VN-200

gstime(ms)

milliseconds

GeoSnap time since power on

AttUncrt(deg)

degrees

Attitude uncertainty of the VN-200

PosUncrt(m)

meters

Position uncertainty of the VN-200

8 8

Pix4D Log File (001-P4D.txt)

The Pix4D log file is a Pix4D compatible log of the image name and position of the camera at the moment of image capture. Information is logged as plain, ASCII text in comma-separated columns.

Pix4D Log File Columns

Label

Units

Description

imagename

name

Image name/counter

latitude

degrees

Latitude as reported by the VN-200

longitude

degrees

Longitude as reported by the VN-200

altitude

meters

Height above WGS84 ellipsoid

Flight Log File (001-FLT.txt)

The FLT log file is a 25Hz log of the position/attitude of the camera throughout the flight. If the log reaches 3 million lines a new FLT file is created with a letter appended to it using the following convention: 001-FLT.txt, 001- FLTA.txt, 001-FLTB.txt, etc. Information is logged as plain, ASCII text in space-separated columns; each column is 14 characters wide.

Flight Log File Columns

Label

Units

Description

gpsdate

YYYY-MM-DD

Date as reported by the VN-200

gpstime

HH:MM:SS.SSS

Time as reported by the VN-200

lat(deg)

degrees

Latitude as reported by the VN-200

lon(deg)

degrees

Longitude as reported by the VN-200

hght(wgs84-m)

meters

Height above WGS84 ellipsoid

roll(deg)

degrees

Roll as reported by the VN-200 (positive roll is a roll to the right)

pitch(deg)

degrees

Pitch as reported by the VN-200 (positive pitch is a pitch up)

yaw(deg)

degrees

Yaw as reported by the VN-200

gstime(ms)

milliseconds

GeoSnap time since power on

AttUncrt(deg)

degrees

Attitude uncertainty of the VN-200

PosUncrt(m)

meters

Position uncertainty of the VN-200

INS_stat

Status of the INS as reported by VN-200

9 9

Imagenum File (IMAGENUM.txt)

This file keeps track of the numbering of the images in the IMG and Pix4D log files. To restart the numbering at 1, simply delete the IMAGENUM file from the GeoSnap microSD card.

SYNCHRONIZING IMAGE NAMES

The GeoSnap does not get the actual image names from the camera but uses a sequential numbering scheme in the specified image name format. Because of this, it is important that the camera and the GeoSnap be set up so that they both start image numbering at 1 and remain synchronized through use.

It is recommended to set the camera’s file numbering setting to Reset (for more information on

this, see the Camera Settings section of this manual). Then, before you start a new mission, clear

all images off the camera’s SD card and delete the IMAGENUM.txt file off the GeoSnap card. This

will reset both systems to start image numbering at 1.

CONFIGURING FOR MAPPING FLIGHTS

For mapping missions, we recommend setting up the GeoSnap to trigger the camera using the distance interval option. The appropriate distance interval can be obtained from your flight planning software, or from Field of View’s flight planning calculator, available at fieldofviewllc.com/downloads. To configure the GeoSnap for distance interval triggering:

1. Insert the GeoSnap microSD card into a computer

2. Open the CONFIG.txt file using a text editor (e.g. Notepad)

3. Edit the following CONFIG file options to the specified settings, then save and replace

microSD card in the GeoSnap

@2: File_name = camera dependent (select the correct option for your camera) @3: Trigger mode = 2 @5: Trigger_dist_m = your desired trigger distance interval in meters @20: Antenna_offset_m = installation dependent (see the Configuration File section of this manual for more information on how to properly use this option)

POWERING ON THE GEOSNAP

To power on the GeoSnap, simply plug in the provided USB power cable, or the power pigtail cable connected to an appropriate power source (see the Specifications section of this manual for power specifications). Before powering down the system, press and hold the onboard button for approximately 3 seconds until all LED shine solid. This ends logging, making it safe to remove power from the system.

Dynamic Motion

The VN-200 requires dynamic motion to reach full heading accuracy. Because of this, if you are using the GeoSnap Pro on a multirotor, we highly recommend performing a few S-turns in manual flight mode at the start of the flight before sending it on its autonomous mission.

10 10

LED CODES

The meanings of the LEDs on the GeoSnap board are explained in this section.

• Blue LED – This LED indicates when the board is powered. When power is sent to the

board, this LED shines solid.

• Red LED & Green LED – These LEDs indicate the status of the GeoSnap, including startup

status, GPS status, triggering, and camera capture indications.

Startup Sequence

LED Code

Meaning

Board is checking for access to the microSD card and writing a default CONFIG file to the card if a CONFIG file does not already exist. *Note: this is also the LED code for an SD card error (see below) so if this pattern persists, check the SD card.

No GPS lock but system is ready to start operating. If the GeoSnap is configured for fast as possible or time triggering, the first trigger command will be sent at this point

GPS lock. If the GeoSnap is configured for distance triggering, the first trigger command will be sent at this point.

Capturing Images

LED Code

Meaning

Trigger command sent.

Capture confirmation received from camera.

Shutdown

LED Code

Meaning

All data logging has stopped and it is safe to power down the system. This occurs after pressing and holding the trigger button for approximately 3 seconds.

Errors

LED Code

Meaning

MicroSD card error. Occurs when there is no card, the card is not seated properly, the card is full, or if the log file number exceeds 999.

11 11

CONFIGURATION FILE

The CONFIG.txt file on the GeoSnap’s microSD card is where you can adjust all of the settings of the GeoSnap. Each time the GeoSnap is powered, it searches for the configuration file and reads the settings. If this file is not present, the GeoSnap creates a new configuration file with default options.

The file consists of human-readable ASCII text and can be edited using many types of text editors. On Windows, either Notepad or Wordpad may be used. On OSX, TextEdit may be used. On GNU/Linux or Unix, EMACS, Vim, Nano, Pico, or other graphical equivalents may be used. Note: word processing software such as Microsoft Word should not be used to edit the configuration file.

The sections below describe in detail the various settings and how their options/values affect the behavior of the GeoSnap.

12 12

Brand-specific infrared LED trigger code

Default String:

@1:IR_LED_code = 0

Values:

0: none (wired shutter release only) [default]

1: Canon 2: Sony 3: Nikon

Description:

If you are using a wired trigger cable to trigger the camera, you can keep this value at the

default option ‘0’. This option was used to control the IR code that is output by the GeoSnap

to trigger the camera via an IR trigger cable (this cable is no longer provided standard with the GeoSnap due to wired triggering being more reliable).

Image file name convention

Default String:

@2:File_name = 0

Values:

0: none specified [default]

1: IMG_0001.JPG (Canon) 2: DSC00001.JPG (Sony) 3: DSCN0001.JPG (Nikon) 4: DSCF0001.JPG (Fuji) 5: DSC_0001.JPG (Nikon)

Description:

This option allows you to specify what will be entered into the “image” column in the image

log file and Pix4D log file. If option ‘0’ is selected, the “image” entry in the log file will be filled with a counter that can be converted to image names in post-processing using

Geotility. If an actual image name is selected the “image” entry in the image log file will be filled with consecutively numbered image names. For example, if option ‘1’ is selected, the entries in the “image” column will take the form of IMG_0001.JPG, IMG_0002.JPG, etc.

13 13

Mode that determines when the GeoSnap system sends a trigger command

Default String:

@3:Trigger_mode = 0

Values:

0: onboard button only [default]

1: time 2: distance 3: fast-as-possible 4: low->high input signal 5: high->low input signal 6: low->high and high->low input signal

7: Garmin portable aviation GPS waypoint arrival/time interval

Description:

Set this option to specify the camera triggering mode of the GeoSnap.

• Onboard button only: a trigger command is sent when the GeoSnap’s onboard

button is pushed.

• Time: trigger commands are sent at a uniform time interval that is specified in the

time interval option.

• Distance: trigger commands are sent at a uniform distance interval (calculated from

the latitude and longitude obtained from the GPS) that is specified in the distance interval option.

• Fast-as-possible: a trigger command is sent immediately after the GeoSnap receives

capture verification from the camera from the prior trigger command.

• Input signal modes (options 4, 5, and 6): a trigger command is sent every time the

GeoSnap receives an external input signal as listed in the option. For example, if ‘low->high input signal’ is selected, the GeoSnap will send a trigger command to the camera every time the external input signal transitions from low to high voltage (for more information on using an external input signal, see the External Connections section of this manual).

• Garmin portable aviation GPS waypoint arrival/time interval (legacy feature): a

trigger command is sent every time a waypoint that is set in a Garmin portable aviation GPS is reached. It will also send a trigger command at the specified time interval when the switch on the handheld remote (part of the Garmin portable aviation GPS GeoSnap solution) is in the always on position.

14 14

For mode 1 or 7 above, specify a time interval in seconds

Default String:

@4:Trigger_time_sec = 2.0

Values:

0.1 - 64800 seconds (in tenth of a second increments)

Description:

This option sets the amount of time (in seconds) between trigger commands sent by the GeoSnap when it is set to time mode triggering (or when the handheld remote switch is set to the always on position in a Garmin setup). This is configurable in tenth of a second increments. The trigger mode must be set to 1 or 7 in order for this option to have any effect on system operation.

For mode 2 above, specify a distance interval in meters

Default String:

@5:Trigger_dist_m = 50

Values:

1 - 10000 meters (in meter increments)

Description:

This option sets the distance (in meters) between trigger commands sent by the GeoSnap when it is set to distance mode triggering. This is configurable in meter increments. Any decimals entered will be truncated. The trigger mode must be set to 2 in order for this

option to have any effect on system operation.

Length of time the GeoSnap system waits for capture verification from the camera before resending the trigger command

Default String:

@6:Resend_trig_time_ms = 500

Values:

0 - 60000 milliseconds

Description:

This option allows you to set the amount of time the GeoSnap waits for capture verification before resending the trigger command. This option gives you control over your mission quality control by allowing you to specify the amount of time to wait and see if the camera took a picture before identifying a missed trigger and attempting to salvage the trigger

point.

15 15

Use external input signal or onboard button to control time mode, fast-aspossible mode, and/or distance mode

Default String:

@7:Control_mode= 0

Values:

0: feature disabled [default] 1: high input signal enables time mode, fast-as-possible mode, or

distance mode

2: low input signal enables time mode, fast-as-possible mode, or

distance mode 3: onboard button starts time mode or fast-as-possible mode 4: onboard button toggles (starts/stops) time mode or fast-as

possible mode

Description:

This option allows you to use an external input signal to enable time mode, fast-as-possible mode, or distance mode; or to use the GeoSnap onboard button to start and/or stop time mode or fast-as-possible mode. If this feature is disabled and the GeoSnap is in time, or fastas-possible mode, it will start sending trigger commands as soon as it is powered. If this feature is disabled and the GeoSnap is in distance mode, it will start sending trigger commands as soon as a GPS lock is acquired.

If one of the input signal options (1 or 2) is selected, time, distance, or fast-as-possible triggering will only be allowed when the external input signal is held high or held low (depending on the option selected). This is useful if images are only desired during a certain portion of the flight.

If option 3 is selected, time or fast-as-possible triggering won’t start until the button is pressed, and subsequent button presses will be ignored. If option 4 is selected, time or fastas-possible triggering won’t start until the button is pressed and subsequent button presses will stop and start the triggering.

Activate time mode or fast-as-possible mode when the GeoSnap system detects an initial image capture

Default String:

@8:Initial_image_activation = 0

Values:

0: feature disabled [default] 1: feature enabled

16 16

Description:

This option configures whether to start time or fast-as-possible triggering after an initial camera image capture has been detected by the GeoSnap. This initial image capture could be initiated using the shoulder button on the camera or with an external signal input.

Send trigger command at least every X minutes to prevent camera liveview timeout

Default String:

@9:Elapsed_time_min = 0

Values:

0 – 600000 min

Description:

This option is designed for use with a manned aircraft setup with Canon Live-View. The Canon camera kicks out of Live view mode after a period of inactivity. This option allows you to have the GeoSnap keep track of length of inactivity (i.e. no camera triggers) and send a trigger command at the specified number of minutes if no activity has happened. For example, if you set the value to 10 and there were no images taken after 10 minutes, the GeoSnap would command a trigger at that point. To disable this feature, simply set the value to 0.

Only allow time mode, distance mode, or fast-as-possible mode within specified pitch/roll angles

Default String:

@10:Enable_PR_limit = 0

Values:

0: feature disabled [default] 1: feature enabled

Description:

This option allows you to constrain the GeoSnap so that it pauses image triggering when the aircraft pitches or rolls beyond a specified limit. For example, when the roll limit is set to 45 degrees, the GeoSnap will not send a trigger command at any time that the VN-200 is outputting roll values greater than or equal to 45 degrees or less than or equal to -45 degrees. A trigger not sent due to aircraft attitude is sent as soon as the attitude falls within the set limits.

17 17

Roll limit

Default String:

@11:Roll_limit_deg = 45

Values:

0 – 180 degrees (to the nearest degree)

Description:

This option configures the roll limit associated with Pitch/Roll limit option. The Pitch/Roll limit option must be enabled for this to take effect. This is configurable in one degree

intervals only. Any decimals entered will be truncated.

Pitch limit

Default String:

@12:Pitch_limit_deg = 45

Values:

0 – 90 degrees (to the nearest degree)

Description:

This option configures the pitch limit associated with Pitch/Roll limit option. The Pitch/Roll limit option must be enabled for this to take effect. This is configurable in one degree intervals only. Any decimals entered will be truncated.

Only allow time mode, distance mode, or fast-as-possible mode above a specified WGS84 altitude

Default String:

@13:Enable_altitude_limit = 0

Values:

0: feature disabled [default]

1: feature enabled

Description:

This option allows you to constrain the GeoSnap so that it pauses image triggering when the aircraft is below a certain WGS-84 altitude. This is useful to prevent image capture while the aircraft is on the ground.

18 18

WGS84 altitude limit

Default String:

@14:Minimum_altitude_m = 50

Values:

1 - 65536 meters (to the nearest meter)

Description:

This option configures the altitude limit associated with the altitude limit option. The altitude limit option must be enabled for this to take effect. This is configurable in one

meter intervals only. Any decimals entered will be truncated.

Associate and log position/attitude data at the moment the trigger command is sent, not when capture verification is received

Default String:

@15:Blind_logging = 0

Options:

0: feature disabled [default] 1: feature enabled

Description:

This option allows you to ignore capture verification completely and associate and log position/attitude data at the time that the trigger command is sent. Since capture verification is ignored when blind logging is enabled, if you are in fast-as-possible mode the GeoSnap will send a trigger command at the interval specified in the Resend_trig_time_ms option (option @6).

Associate position/attitude data with the image ‘x’ milliseconds after

capture verification is received

Default String:

@16:Association_delay_ms = 0

Description:

This option allows you to add a delay between when the GeoSnap received capture verification and when the position/attitude association is performed and written to the

image log file.

19 19

Select which log files to generate

Default String:

@17:Data_logging = 0

Options:

0: generate image log, pix4d log, and flight data log [default] 1: generate image log and flight data log only 2: generate image log and pix4d log only 3: generate image log only

Description:

This option configures whether or not to create and populate the IMG, P4D, and/or FLT log files on the GeoSnap’s microSD card.

VN-200 orientation relative to the camera

Default String:

@18:VN_orientation = 0

Options:

0: default orientation [default] 1: custom orientation

Description:

Use this option to select the orientation of the VN-200 relative to the camera. The default orientation (0,0,-1,0,1,0,1,0,0) is appropriate for the standard GeoSnap installation on the hotshoe of the camera. In this orientation the X-axis of the VN-200 and the camera lens are pointing in the same direction, with the Z-axis of the VN-200 pointing down out of the bottom of the camera. If the VN-200 is mounted in a different orientation relative to the camera, select option 1 and specify the appropriate reference frame rotation in the following option.

For option 1 above, specify the reference frame rotation for the VN-200

Default String:

@19:Reference_frame = 0,0,-1,0,1,0,1,0,0

Values:

C00,C01,C02,C10,C11,C12,C20,C21,C22

is translated to



  























  





20 20

Description:

This input defines the transformation matrix required to align the body frame of the VN-200 to the camera frame of reference. This allows for the VN-200 to be placed in any arbitrary orientation with respect to the camera. The default string is the appropriate string for the standard mounting configuration of the VN-200 on the GeoSnap hotshoe module.

The variables {X, Y, Z}B are a measured parameter in the body reference frame with respect to the VN-200. The variables {X, Y, Z}C are a measured parameter in the camera’s frame of reference.

GeoSnap performs an internal transformation to assign the standard aircraft coordinate system to the camera so that the Z-axis is pointing out of the lens, the X-axis is off of the top of the camera, and the Y-axis is off of the right of the camera. This can be seen below.

The matrix equation translates to the following three linear equations:

      



      



     



Y X Z

21 21

As an example on how to determine the values in the transformation matrix, let’s look at the default configuration of the VN-200 mounted on the GeoSnap hotshoe module on a

DSLR.

As can be seen above, the X axis of the camera contains all of the negative Z axis of the VN200 and nothing else, the Y axis of the camera contains all of the positive Y axis of the VN200 and nothing else, and the Z axis of the camera contains all of the positive X axis of the VN-200 and nothing else. Putting this into equation form gives:













Which gives the following linear equations:

     󰇛󰇜 



        



        



This goes into the matrix equation as:



  









        



  





Which gives our default string of: 0,0,-1,0,1,0,1,0,0.

XC

YC

ZC

XB

YB

ZB

22 22

GPS antenna offset in meters, PosX,PosY,PoxZ

Default String:

@20:Antenna_offset_m = 0,0,0

Values:

PosX,PosY,PosZ

Description:

The GPS antenna offset is the position of the GPS antenna relative to the VN-200 in the camera coordinate frame in meters. An example of this can be seen below where PosX = 1,

PosY = 4, and PosZ = -3.

NOTE: Keep this value at the default of 0,0,0 if the GeoSnap hotshoe module (and VN-200) is installed on a camera that is on a gimbal. When the VN-200 is on a gimbal and the antenna is not, there is no longer a fixed coordinate frame between the two, so programming an antenna offset is no longer applicable, and can result in less accurate position values.

Send initialization commands to the VN-200 and report the settings and status in log file headers

Default String:

@21:VN_initialization = 0

Values:

0: feature enabled [default] 1: feature disabled

XC

YC

ZC

23 23

Description:

If this feature is disabled, the VN-200 settings and status (such as reference frame rotation, GPS antenna offset, etc.) will not be displayed in the header of the image and flight data log files.

Reset all VN-200 settings

Default String:

@22:Factory_reset = 0

Values:

0: feature disabled [default] 1: feature enabled

Description:

If enabled, this causes a factory reset command to be sent to the VN-200. Enable this if you need to reset the VN-200 for any reason, but do not leave this option enabled as it would cause a factory reset command to be sent to the VN-200 every time the system is powered

on, causing an unnecessary increase in startup time.

24 24

AUXILIARY I/O CONNECTIONS

The 6-pin Auxiliary I/O port can be used to interface the GeoSnap with external devices. A 6-pin locking connector and three wires with pre-crimped pins are provided in the GeoSnap accessories for this use. To install a wire into the 6-pin locking connector, place the wire into the appropriate slot with the smooth side of the pin facing up. Push the wire in until you hear a click,

then tug on the wire slightly to ensure that it seated.

Auxiliary I/O Port Pinout

Label

Voltage

Description

1

Ground

-

2

RS232-in

-15 to 15V

Not currently operational

3

RS232-out

-15 to 15V

Not currently operational

4

Trigger

0 to 5V

Control GeoSnap by driving this line high (3.3-5V) or low (0-0.2V)

5

Indication

0 or 3.3V

Line goes high (3.3-5V) when capture verification is received

6

VCC

3.3V

Only for use with the Trigger line (position 4). Should not be used to power any external device.

External Trigger Input

The GeoSnap board can be triggered externally by an autopilot, handheld remote, or other input by driving Pin 4 high (3.3-5V) or low (0-0.2V), depending on the settings you have chosen in the configuration file (see options @3 and @7 in the Configuration File section of this manual for more information). There are two primary ways that this can be done:

Short Together Pin 4 and Pin 6 (recommended)

It is highly recommended that you use Pin 6 to provide the voltage to hold or drive Pin 4 high. This can be done by simply shorting together Pin 4 and Pin 6 using a switch or relay.

Inject 3.3-5V into Pin 4

You can also inject 3.3-5V into Pin 4 using an external device (e.g. autopilot). If this is the case, the external device and the GeoSnap must share a ground (Pin 1 can be used for this purpose).

Pin 1

(indicated by triangle)

25 25

UPDATING FIRMWARE

To load new firmware on your GeoSnap, follow these steps:

1. Erase all data from the microSD card.

2. Copy the firmware file (FOV.fwu) to the root folder of the microSD card.

3. With the GeoSnap powered off, insert the microSD card into the GeoSnap.

4. Power on the GeoSnap.

5. Wait for a few seconds while the firmware file loads (the alternating red and green LEDs

will be flashing).

6. Once the GeoSnap is only blinking the green LED, you can power down the system.

7. The firmware file will have been automatically erased from the microSD card. You can

check that the firmware was updated successfully by checking the firmware number listed in the first line of the CONFIG file.

26 26

OPERATIONS CHECKLIST

GeoSnap Pro file setup

□ File name type (Sony, Canon, etc) □ Trigger mode (distance, time, etc) □ Trigger mode parameter (# meters or # seconds) □ Resend trigger time (typically around 750ms) □ Control mode (none, button toggle, etc) □ GPS antenna offset (optional)

□ Delete IMAGENUM.txt file off of the card if you want the IMG log to start at 1

Camera setup

□ Insert fully charged battery into camera □ Insert empty SD card into camera □ Make sure all of the settings are correct

o Shutter priority, 1/1000s (shutter speed)

o ISO Auto

o White Balance Sunny/Cloudy

o MF (Manual Focus) – lens focused at infinity and taped down

o Single capture – remote shooting

o Large image quality

Pre-flight system checks

□ Lens cap is off camera and lens is clean □ Hotshoe module is on the camera and tightened down □ GeoSnap/camera trigger cable is in place and secure □ GeoSnap microSD card is in the GeoSnap control module □ GeoSnap GPS antenna is connected and antenna is mounted securely □ GeoSnap and camera are securely mounted on aircraft

Powering the system

□ Power on camera □ Plug in GeoSnap □ Watch for GPS lock on GeoSnap (green LED will start flashing quicker) □ If in distance trigger mode, watch for first trigger (when GPS lock is obtained) □ Take-off and perform dynamic motion to initialize VN-200

Post-flight

□ Press and hold GeoSnap onboard button to stop logging □ Power down GeoSnap and camera □ Remove GeoSnap microSD card and camera SD card

27 27

CAMERA SETTINGS

Required and Recommended Settings

To obtain good aerial images when performing a mission using the GeoSnap it is necessary that certain settings be applied to your camera. The following table addresses the required and recommended camera settings to help ensure successful imaging missions. Refer to your

camera manual for information on how to adjust these settings.

Required Settings

Setting

Value

Description

Drive Mode

Remote control

Often required for triggering the camera using the IR LED or the wired remote

Focus Drive

Manual focus

-

Focus Distance

Infinity

Set the focus so objects are sharp at infinity and lock down the lens in that position by using a piece of tape or something similar

Shoot Mode

Shutter priority

-

Shutter Speed

1/1000 or faster

Required for sharp images while the aircraft is in motion

Recommended Settings

Setting

Value

Description

Flash Mode

No flash

-

ISO

Auto

-

White Balance

AWB

-

Shading/Peripheral Illumination

Enable/Auto

Enable any shading or peripheral illumination correction option

Chromatic Aberration

Enable/Auto

Enable any chromatic aberration correction option

Distortion

Enable/Auto

Enable any distortion correction option

28 28

Image numbering

DSLR-style cameras typically have two main options to handle file numbering. (The Canon 6D has Continuous and Auto Reset; the Sony A6000 has Series and Reset). Continuous/Series file numbering continuously numbers the images, even between power cycles or between cards, etc. When the file numbering is set to Continuous, the Canon 6D has an option to reset the numbering back to 1 by selecting the Manual Reset option. This will reset the numbering back to 1 then return to continuously numbering the images from there. The Sony A600, however, does not have a Manual Reset option. Auto Reset/Reset file numbering resets the file numbering to 1 anytime that there is an SD card inserted that has no images on it or that the camera card is formatted.

Method 1

The recommended method for handling file name synchronization is to set the camera’s file

numbering setting to Auto Reset. Then, before you start a new mission, clear all images off of

the camera’s SD card and delete the IMAGENUM.txt file off of the GeoSnap card. This will reset

both systems to start image numbering at 1.

Method 2 (only for Canon 6D)

(Note: This method requires unobstructed access to the camera screen and menu buttons.)

Alternatively, you can set the Canon’s “File numbering” option to Continuous and do a Manual

Reset to start it at 1. Delete the IMAGENUM.txt file off of the GeoSnap to start it at 1, but then do not delete the IMAGENUM.txt file after that. Both the camera and GeoSnap will then continue numbering between flights. However, if there is the need to reset numbering to 1 (e.g. the IMAGENUM.txt was accidentally deleted off the GeoSnap card or image numbers hit 9999 and reset) then you need to synchronize the numbering again by deleting the IMAGENUM.txt

file and doing a Manual Reset on the camera’s file numbering to get both of them synchronized

back to 1.

Camera cycle time considerations

When using the GeoSnap to trigger your camera at a distance interval, the maximum ground speed that should be allowed during your flight is a direct function of your desired trigger distance interval and the cycle time of your camera. Every camera has a limit on how fast it can take pictures (ranging from sub-second to over 4 seconds, depending on the camera), so, if you are trying to take images at consistent distance intervals, you have to fly at a speed at which the camera can keep up. The equation to use is:

󰇟󰇠

󰇟󰇠

󰇟󰇠

29 29

The cycle time of a camera is dependent on its buffer size, processor write speed, image size, SD card write speed, etc. To figure out the cycle time of your camera system, set the GeoSnap to

time triggering and set the time interval to a reasonable guess for the camera’s cycle time (for

most DSLR-style cameras, a good starting point is 1 sec). Point the camera at a complex scene (outside the window works well) as this can affect the file size of the images, and thusly the cycle time of the camera. Start time triggering with the GeoSnap and let the camera trigger for several minutes until you are confident that it can keep up with the commanded cycle time. If the camera starts lagging or missing images, try increasing the time interval. If the camera is keeping up, try reducing the time interval. Continue this testing until you are fairly confident you have found the camera’s fastest cycle time at which it can sustain triggering indefinitely. We then recommend doing a long test (at least the length of your mission) to make sure that the camera keeps up over the mission length.

Field of View has performed cycle time testing with various cameras, and the results are shown below. Note that these numbers are for reference only, and it is still highly recommended that

you perform your own testing!

CAMERA

FILE FORMAT

SD CARD

TEST

LENGTH

MIN CYCLE TIME

SONY A6000

JPEG, Fine

32GB SanDisk Extreme

Pro (95 MB/s read speed,

90 MB/s write speed)

20

minutes

0.8 seconds

SONY A7RII

JPEG, Extra Fine

1.5 seconds

SONY A7R

JPEG, Extra Fine

1.5 seconds

30 30

TROUBLESHOOTING

GPS signal quality test

There are a variety of transmitters and components on an aircraft that can degrade the GPS signal received by the antenna if it is placed in a poor spot and cause you to log poor GPS data in your FLT and IMG log files. Because of this, it is best to test your setup for GPS signal quality

after installing your GeoSnap on your aircraft.

BASIC TEST

To run a quick test to identify if you are getting good GPS data, perform the steps outlined in this section.

• Set the GeoSnap to the bench test settings (i.e. button toggle).

• With everything installed on your aircraft, place it outside in an area that has a clear

view of the sky (i.e. in a clear open area, not near tall buildings, trees, or power lines).

• Power on the GeoSnap and wait for it to get a GPS lock (signified by the green LED on

the GeoSnap control module flashing rapidly).

• Start image triggering on the GeoSnap by pressing the onboard button.

• Power on the rest of the systems on the aircraft (including any video transmitters) on

the aircraft and, if using a multicopter, set the motors to idle (make sure you take appropriate safety measures around the spinning propellers).

• Let the system sit for 3-5 minutes to allow the GPS on the GeoSnap to stabilize and to

get a good dataset.

• Power everything down.

• Remove the GeoSnap’s microSD card, plug it into your computer and open the FLT log.

• Look at the PosUncrt column in the FLT log. It should start out with fairly high

uncertainties (≈15-20m) that rapidly decrease and stabilize at uncertainties ≤2m (ideally ≤1m).

• If the PosUncrt stabilizes at a value greater than 2m, there is likely some interference

happening with the GPS signal and further testing will have to be performed to identify what on the aircraft may be causing the issue.

31 31

IDENTIFICATION TEST

If you are getting poor GPS data (i.e. PosUncrt > 2m), run the test outlined below to identify what system(s) on your aircraft are causing a degradation of the GPS data.

• Set the GeoSnap to the bench test settings (i.e. button toggle).

• With everything installed on your aircraft, place it outside in an area that has a clear

view of the sky (i.e. in a clear open area, not near tall buildings, trees, or power lines).

• Power on the GeoSnap and wait for it to get a GPS lock (signified by the green LED on

the GeoSnap control module flashing rapidly).

• With everything except the GeoSnap still powered off, let the system sit for 3-5 minutes

to allow the GPS on the GeoSnap to stabilize and to get a good baseline dataset.

• Power on the rest of the systems on the aircraft and press the GeoSnap onboard button

twice to turn on and off triggering (this is to trigger one image to act as a timestamp to mark when you powered on the rest of the systems).

• Let the system sit for 3-5 more minutes with everything powered on.

• If using a multicopter, trigger another single image (to act as another timestamp) with

the GeoSnap by pressing the onboard button twice, then set the multicopter motors to idle (making sure you take appropriate safety measures around the spinning propellers).

• Let the system sit for another 3-5 minutes with everything powered on and the motors

running.

• At this point, use the button on the GeoSnap to start triggering (if using a multicopter,

turn off the motors if necessary to safely access the GeoSnap then, once the triggering is started, set the motors back to idle).

• Let the system sit for 3-5 more minutes with everything powered on, the motors

running, and the camera taking images.

• Power everything down.

• Remove the GeoSnap’s microSD card, plug it into your computer and open the IMG and

FLT logs.

• In the IMG log, make note of the gstime (located after the yaw column) of the first three

images (i.e. when you powered on the rest of the systems, when you started the motors, and when you started triggering).

• In the FLT log, look at the PosUncrt column. It should start out with fairly high

uncertainties (≈15-20m) that rapidly decrease and stabilize at uncertainties ≤2m (ideally ≤1m) when just the GeoSnap is powered on.

• Scroll down until you find the gstime in the FLT log that corresponds to when the rest of

the systems on the aircraft were powered on. Look at the PosUncrt column to see if the uncertainties increase noticeably after that point.

• Do the same process with the gstimes corresponding to when the motors were started

and when camera triggering was started.

• If the uncertainties increase noticeably after any of the marked occurrences (i.e.

systems powered on, motors started, or camera triggering started), perform the GPS

32 32

test again with the corresponding system not operating (e.g. if there was an increase in PosUncrt after the motors were turned on, place the aircraft outside with all of the systems powered on and the camera triggering but with the motors turned off).

• If the resulting uncertainties are ≤2m, then you know that the GPS issue is coming from

the identified problem (in this example, the motors being powered).

• Try moving the GPS antenna to a better location on the aircraft, away from any

components that may be causing the interference, and re-run the test, looking for ≤2m uncertainties. Or, if the interference appears to be coming from an expendable system

(e.g. a video transmitter that doesn’t need to be running during the flight), try turning off that system and re-running the test, looking for ≤2m uncertainties.

INS_stat code lookup tables

INS_stat GPS/INS status (xxxX)

Column

GPS

INS

0

No fix

Not tracking; insufficient dynamic motion

1

No fix

Tracking; not within performance specs

2

No fix

Tracking; within performance specs

4

Fix

Not tracking; insufficient dynamic motion

5

Fix

Tracking; not within performance specs

6

Fix

Tracking; within performance specs

INS_stat Error Codes (xxXx)

Value

Time

IMU

Mag/Pres

GPS

0

1 x

2 x

3 x x 4 x

5 x x 6 x x

7 x x x 8

x

9 x x

A x x

B x x x

C x x

D x x x

E x x x

F x x x x

33 33

SPECIFICATIONS

Physical specifications

GeoSnap Pro hotshoe module dimensions (in millimeters).

GeoSnap Pro control unit dimensions (in millimeters).

GeoSnap Pro Weights

Component

Weight

Control unit (with microSD card)

24 g

Hotshoe module

34 g

Cabling

10 g

GPS antenna w/ 1 m cable

32 g

Total system weight

100 g

34 34

Power specifications

GeoSnap Pro Power Requirements

Parameter

Value

Voltage input range

4.5 to 28 V

Current input (typical)

0.10 A

MicroSD card specifications

The microSD card used in the GeoSnap must be formatted as FAT32 (exFAT is not supported). We recommend using a Sandisk Ultra microSD card, and have successfully tested the system

with 4GB, 8GB, and 16GB SDHC cards.

To use a new microSD card in the GeoSnap, make sure it meets the requirements above and is blank. Insert the card into the system, power on and wait for a couple seconds, then power down and remove the card. The card will have been populated with a default CONFIG file that you can edit to your requirements.

FIELD OF VIEW GeoSnap Pro User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual