web design templates

Live Overlay of Wind & Race Maps

An article in the Australian sailing news in 2015 gave some hints about new capabilities emerging with the wireless SailTimer Wind Instrument™. Because the Wind Instrument is a connected device, it can be a remote sensor accessible from your tablet or smartphone. That means there are no wires to install on your boat, which is good -- but it also means that you can check wind conditions on your boat from home or office -- and also that you can share or "crowdsource" your wind data.

Imagine live wind maps of where you want to sail. That has never been possible before. Live wind maps are much better than coarse weather forecasts and GRIB simulations, made hours ago at an airport or government office far away. You can set your sails based on a live wind map, but you would never blindly set your sails based on a weather forecast. It has never been possible for government weather agencies to have blanket coverage of live wind data from precise positions -- but crowdsourcing does make this possible with the wireless SailTimer Wind Instrument. The more sailors that share wind data, the better the live overlay gets.

Our initial focus in 2016 was on getting the infrastructure set up with the wind and race maps (live and replays) at SailTimerMaps.com. Now in early 2017, a live overlay is also available in the SailTimer app (and Charts Edition app - referred to interchangeably here). Here's how to use it.

Live Overlay: To turn on the Overlay, under the Options button (lower left corner of the screen), go to Live Wind & Race Maps. We needed to add a login to the SailTimer app and Charts Edition, so that you could view and/or share data on the live wind & race maps. You only need to log in the first time, and your login is retained for when sailing offline. If you want a bigger screen, you can do the registration at SailTimerMaps.com, then in the app just log in.

When you turn on the Overlay button, you'll see any other users around you who are sharing their live wind and/or GPS data. Boats sharing data will appear on the map with blue icons like in the screenshot below from the SailTimer app. (Your own boat has a yellow dot when stationary, and a yellow boat icon with a red needle pointing ahead when moving.) Note the wind barb below indicating the live wind conditions at that location. The arrow on the wind barb shows the wind direction. Each short line indicates 5 knots of wind speed, and each long line indicates 10 knots.

Sharing: By selecting Overlay you can see other boats who are sharing their GPS movement and wind data if available. There is also a Sharing button that lets you similarly contribute your own data to the map overlay. You do not have to turn on Sharing, but if you share live data with the community of sailors in your area, it improves wind maps and tacking routes for all. Maybe you have wind data available from an old wired anemometer or the wireless SailTimer Wind Instrument, to let others see wind conditions out on the water. Or maybe you want sharing on to let someone at home check on your position to know when you'll be home for dinner.

Events: Crowd-sourcing is also very useful for an audience on shore or in a sailing club to watch a live race in the app, or for you to save, share or replay your voyage or race. It used to be very expensive to have a tracker on board, but now with a cellular connection, wind and race maps (live and replays) are easily accessible for ordinary sailors. (You don't even need the cellular connection at SailTimerMaps.com, because you can Create an offline event there, and save the data in your web browser until you return to wifi again.)

If you want to save or let someone else watch your GPS track and wind conditions for your own daysail or for a race, you can Create or Join an event at SailTimerMaps.com. And now as a first step in the app, you can replay events with GPS tracks with wind conditions, like in the screenshot below.

Demo Replay: Under Events, you can enter the name of an replay you received from someone else, from a race committee, or a replay of an event you recorded yourself. The example below is a demo of catamarans in the lead-up to the 2013 America's Cup (used with permission). It is available as a demo replay under Events. Try it out in the app; it's fun.

The controls are 4 circular icons in the lower right of the screen, that appear once the replay opens. The > is the Play/Pause button. The >> allows you to speed up the replay 2x, 10x or 30x. The ~ lets you select the length of the GPS track to display. The X clears the screen. The plus/minus buttons in the upper right of the screen are always there for zooming in and out. The cross-hairs in the upper left of the screen are the "follow-me button". Leave it white to move the view around. It turns blue when tapped if you want to keep your position in the center of the screen.

Pop-up for boat data: In this sample replay, you can see the tacking route from each boat, and also a wind barb on many of the boats. The wind barb symbol shows the wind directon graphically and gives you an approximate wind speed. But what if you want exact data on the wind conditions and boat's heading and speed? During a replay, just tap on a boat icon. That will open up the pop-up panel below, showing further details from the boat selected.

More features are planned for performance analysis, but now in the SailTimer app you can replay tacking routes and wind conditions, and can view the live overlay from boats around you who are sharing. If they have the wireless SailTimer Wind Instrument™, they can easily share wind data to these live wind maps. And now with the SailTimer Air Link™, it is even possible to connect older wired anemometers to wireless apps and our online database, so that all anemometers can contribute crowd-sourced data.

This data is all free and easily accessible, giving ordinary sailors advanced capabilities that required sponsors or onboard tacticians in the recent past. Now you can plan your next tacking angle based not just on the winds from your own masthead, but knowing the wind conditions on boats up ahead. Coaches at a sailing school can talk about tacking decisions with a replay of the dinghy sailor's GPS tracks and wind conditions. Or you can check live wind conditions out on the water while you are still at home or office. That has never been possible before.

Part 1: How to Use the SailTimer App

Part 2: Learning your boat's polar plots, graphing wind speed, and converting True/Apparent with live wind data...