Helmsman's Kit: Instructions

Disclaimer

Always use official maps for navigation. Do not rely only on an app for your safety. The sensors of a smart phone are usually not as accurate as professional sensors. E.g. the accuracy of your compass depends strongly on the history of the device. If it was placed near a magnet (e.g., the magnetic cover of the iPad), it is usually strongly magnetized and the accuracy of the compass will not be below 10°-20° even directly after calibration.

Marine Instruments Display (MID)

The following abbreviations are used for the display of the available sensor information:

φ	Latitude in degrees (GPS)
λ	Longitude in degrees (GPS)
HDG	True Heading (compass)
SoG	Speed over Ground (GPS)
CoG	Course over Ground (GPS)
HEL	Heel angle (accelerometer)
LOG	Distance traveled for the current track (enabled in map view).
AVS	Average speed of current track
TME	Time since start of current track.

Compass

The 3D compass was intended to provide the usual look and feel of a spherical compass. If you are used to it, you will grasp at a glance the heading and the heel angle of your ship (the side view lines are not really useful on a flat display, but they are nevertheless included to give you the right feeling ;-).

On the top left corner the current speed over ground (from GPS) is displayed.

If you press the MOB (Man-Over-Board) button, a red arrow will show the direction to the location stored at the moment when you pressed the button. The distance in Meters to this location is shown in red above the compass. Press MOB again to cancel this mode. MOB can be disabled in the settings, if you don't use this app on board of a ship.

Map

This is the usual map view. The OpenStreetMap and OpenSeaMap tiles are used for this display. The display of sea marks can be disabled in the settings.

You can start tracking with the toggle switch "Tracking". The current track will be plotted in blue and LOG, AVS, and TME are updated on the MID view. The stored track is added to the list of tracks, marked with start time and date.

Be aware, that location updates in background mode consumes additional power, reducing the overall discharge time of the device.

Bearing

The camera is used as a bearing compass. You can zoom in and out, after pressing the round button the bearing will be shown on the map. It can be removed again in the menu. Be aware, that the resolution of the built-in compass is limited.

Tracks

In this view you can select the tracks you have recorded. The tracks are stored as GPX file and can be accessed via iTunes from your PC or sent with the "sent" button on the map display of the track. You will find a whole bunch of free applications on the web to display these files, include them on web sites, or to analyze them.

Anchor Watch (Menu item in Maps)

In the anchor watch view you can set the position to watch and enable the anchor watch. You define the center of a circle and its radius in Meters as safe zone. As soon as the device leaves this circle every minute a new alarm is sent.

The safe area is shown as green circle on the map.

If you have a second iOS device, you can use one device for anchor watch and send the alarm in addition to the second device. For this, you have to send the device ID of the second device, e.g. via AirDrop or Mail, to the anchor watch device. Both devices need to have an internet connection for the delivery of notification events. You can test this notification.

Anchor watch requires location updates in background mode. Connect your device to power to make sure that the anchor watch will not be ended by an empty battery.

Offline Maps (Menu item in Maps)

Visited tiles are automatically added to the cache.

It is possible to download a limited amount of offline maps. Just choose the desired map region and start download in the menu. Since a lot of small files are transferred, the download is a quite slow process.

You can clear the cache agin in the menu, or abort the download.

For the preparation of a cruise, download an overview and just zoom in on the habours where you need more details. You can also follow the coast line in a high zoom level to just add the relevant tiles to the cache.

Settings (Menu item in Maps)

Coordinates: The preferred format for the display of coordinates. The iPhone uses WGS84 coordinates.
Update Track Points: The frequency of track points. "1s" means a new track pointe every second. In this mode, up to one day can be stored in a single track.
Download Zoom Levels: When you download the offline map, not only the current zoom level is loaded, but the following levels given by this option. Depending on the screen resolution of your device, the first zoom level corresponds to around 32 Tiles, the next is 4*32=128 Tiles, and so on. The whole world is level 1, the smallest scale for download is level 16 (billions of tiles for the whole world). Use carefully and read the open street map terms.
Allow Compass Calibration: Allow the calibration view to appear whenever the iOS thinks it's necessary. Usually the iPhone calibrates during usage without the need for the calibration view.
Man-Over-Board: Here you can disable the MOB button, e.g. if you don't use the app on board of a ship.
Seamarks: Display the OpenSeaMap seamark overlay.

Contact

Harald Merkel
helmsman@merkel.de