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StartLine

Android Racing Application
Edited 1/30/2015


NEW

StartLine now has a Pebble app? Just search StartLine in the Pebble app store.

NEW

StartLine will now interaface to onboard instruments over BlueTooth using the L-36.com Race Box that can be easioly built with $100 to 200 in parts depending on how fancy you want to get. Contact me for details. You don't even need to know how to solder!

Preface

StartLine is a very powerful racing app, second only to Expedition. Unlike Expedition, it is free. However, I limit the number users because along with the app comes a huge amount of support both to get the full potential out of the app but also to help users improve their race results. Users must agree to contribute to the StartLine community by providing feedback on results or actually participating in the ongoing development which may just be to ask for new features. You must be serious about racing and commit to put in the time to learn the app. It will improve your race results as it has for the other users. It is a small community but already has a podium finish in a prestigious regatta. Read this somewhat outdated manual below and let me know if you are interested in joining the StartLine team.

Overview

StartLine is a racing app for Android phones and tablets that I developed and sold for a short time. I have continued the development and at this point the new version is "Under Development". Actually, it is stable and winning races, it is just that I will never stop improving it so I say Under Development. I will give anyone who purchased the commercial version a new copy if they just ask. I have also given people who show an interest in helping the development process copies for testing. Everyone who gets a copy has sent me an e-mail explaining how they will meet the terms and conditions of the software as well as agree to give feedback on how it works for them. I used it last season in our club races. There are lots of reasons we did well and I would say the racing helped my app development more than the app helped my racing but we did win 80% of the races.

I use this myself and my crew uses it. This page documents the latest version for those who are interested. Please feel free to comment. Note that at this point I have no plans to ever sell the program again. I will give it away as stated above. I do reserve the right to sell it in the future if I change my mind.

Fundamentally, StartLine helps you get a good start by telling you the best it can how long it will take you to get to the line assuming you are traveling at a target speed and direction. If you have calibrated your approach, you would know how long it will take you to get into that target situation so you might, for example, reach down the line knowing that with 4 seconds to burn you need to harden up and go for the line. The fundamental readout, besides time to the start, is time to burn. That is the difference between the seconds to the start and the seconds it would take you to get to the line at your target speed and direction. The latest version also has the ability to compensate for boat speeds that are different than your target so that if you, for example, need to slow the boat down during the pre-start, that is taken into account.

There are some new features incorporated into StartLine that are somewhat unique and deserve special mention. The Waypoint screen, that shows relative direction and time to the waypoint along with boat speed, now also shows distance to the layline. This layline calculation takes the boat target speed and angle as well as the current into account. There are a series of Wind pages. You can set the true wind by heading the boat either directly into or away from the wind. The unique feature about this is that current is also taken into account. There is a current screen that can be used to measure the current using the boats log and compass or it can be entered from a chart. Wind speed and direction can be used to set start targets if a calibration run cannot be done. Finally, there is a "next leg" screen that will calculate the apparent wind angle for each leg of the race. This can be used to pick the side of the boat for the spinnaker set as well as calculating if you can even fly a spinnaker on that leg.

The remainder of this write up is a page by page description of what the app does. There is a short write up on how to use it at the end.

Section 1 - Operating Manual

Opening Screen and Main Menu

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This is the first screen you will encounter. You need to read and agree that this is not an aid to navigation, that racing is dangerous, and all the other stuff I could think of to let you know that you are responsible for making sure this app works and for your own safety. Scroll down and click "Agree" if you agree.

Once you agree, you will be greeted by the main menu. You will return to this menu between other pages.

We will now discuss each option.

Terms

StartLine is an Android application for use by people racing sailboats. It is not for navigation. Racing sailboats is inherently dangerous and should you decide to race, you are taking all responsibility for whatever happens. You can crash your boat or even die. It is up to you to make sure that doesn't happen. StartLine will not make it safer to race and in fact may make it more dangerous by helping you get to the same spot everyone else wants to get to thus increasing your risk of collision.

StartLine has no location data as part of the program and it is your responsibility to insure that any data you put in, either from a button push or a data entry, is accurate. Please be aware that even with accurate data, there may be and probably are errors in the program that may cause any given readout to be wrong.

By its nature, GPS position information will be inaccurate. If you use your phone or tablet built in GPS, the location errors will be so large that this program may be unsuitable for the application. Errors of 60 feet or more should be expected. With an external differential GPS connected by Bluetooth, these errors are approximately half.

The use of Bluetooth GPS units requires the use of a Bluetooth GPS interface program such as "Bluetooth GPS Provider." These programs can lose Bluetooth lock at any time, some worse than others. StartLine has no ability to deal with a loss of lock from the Bluetooth or internal GPS unit.

All readouts of direction to a mark are just that, the direction to the mark. They are not an indication of the direction your boat should go and in most cases you should not and can not follow the indicated direction due either to the wind direction or obstructions. StartLine is not for navigation, it is for racing.

StartLine should only be used after carefully evaluating its usefulness to your application in a safe environment such as a closed parking lot where you can walk around and get familiar with the program.

By pressing the button below, you acknowledge that you have read and understood the above disclaimer.

License

Startline will work for 15 minutes without a license. You cannot use it for racing without a license. Licenses are free but you must qualify to get one. There are no ads and no in app purchases. You must be a serious racer and want to use StartLine to improve your results. I ask that you share what works and what doesn't, interact in developing and testing new capabilities, and basically become a StartLine team member. I also ask that you send an e-mail showing that you understand the terms. The initial license will be for about 30 days. If you are seriously using the app, finding things you want to add, finding any bugs that may be left in there, you will get a permanent license eventually. The app is very stable at this point and had done well in major regattas. There is a page for entering licenses that you will see if you do not have one. Be sure to save the license before continuing.

Timer

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Use this page to set the start time for the race or to set the count down sequence.

Displays

Buttons

Note that all the + and - buttons work on either Start Timer mode or Start Time mode and work regardless if the timer is running or stopped. If your timer reads 4 minutes when it should read 3 minutes, hit -1m.

Setting Marks

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In addition to pre-programmed marks, discussed later, there are a series of marks that can be set based on your location when you press the very large button on the bottom of the screen following any one of the menu choices. Once the mark is pinged, the distance and relative direction are shown. You should see perhaps 30 feet at 180 degrees as you sail away from the mark location. The accuracy will show in red if it is higher than you should expect from a Bluetooth GPS puck with WAAS. The Pin and CB marks define the starting line and must be set to use the starting line functions. The Pin and CB can also be set manually from one of the files screens discussed later. There is a timer in the set marks page that will return you to the marks menu after 30 seconds so you do not have to press any buttons after setting a mark. This is a safety feature. Is 30 seconds too long? Note: It is a good idea to clear old marks before each race.

Instead of pinging a mark, you can enter an offset from your present location by entering the course and direction of where you want the new mark to be. The display will show both the magnetic and true bearing. You can use the heading of the line or the course the boat is on as the bearing reference with the buttons provided. Readouts of the new latitude and longitude are in the small font near the save button.


Save Recall Marks

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On the Save Recall Marks screen you can name and save groups of marks. You can edit the set of marks, deleting some for example, and then name them and save them. You can then later recall your saved group and append them to the end of the active set. The last mark of any given name in the active set it the one that is used. For example, in this screen, the Pin has been entered 4 times. Only the last instance will be used.

Target Menu

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StartLine measures the distance to the starting line but displays this as the time remaining until the start minus the time it would take to get to the line at the target speed and angle to the line. It is really just a translation from meters to time but shows just the excess time you have before you need to be going that speed and angle. If you have the targets set correctly, you would do your normal pre-start until you have just the time to burn that you need to actually get to that speed and heading. For example, you might be reaching down the line and need 4 seconds to turn and get to speed. You would then head down the line until the time to burn read 4 seconds and head the boat to close hauled and go for it. You can see from the way the time to burn changes if your actual VMG to the line is faster or slower than your target. If the time to burn is increasing, you are going too fast. Decreasing, you are slow either because you are not up to speed, or you have the wrong target or can't sail your planned course because of traffic. The idea is that dealing with this one number instead of distance, start time, and boat speed, as you would with a readout of meters to the line, makes it much easier to know what to do. It is not magic, you still need to adjust to the realities of the traffic, changes in wind, etc. It just gives you one number to deal with instead of many and that number takes many of the variables into account for you.

There are four ways to set targets. The preferred way is to do a practice start using the set targets CAL function. You press the CAL button at a critical time in your start sequence. For example, at the point when you switch from a reach to a beat. But whatever it is, you will need to know that exact same corresponding moment during the actual start. Once you cross the line during this practice start, targets and the "Time to Turn" are recorded. During your actual start, this Time to Turn is your target Time to Burn. You can also stop your practice by pressing the button again.

You can set targets manually on the set targets manually page. There you can adjust your boat speed if the conditions change. You can also get to this page from the start screen if you need to make last moment changes. One last moment change you might want to make is to just use the boats actual speed and course at that moment to set the targets. Hitting the use Actuals button twice will set the targets and return you to the start screen.

The final way to set targets is to use the wind and upwind targets. The wind pages, along with the current page, can be used to do this. In this case, targets for port tack and starboard tack are computed and used until you modify them with one of the other ways of setting targets. Then manual targets take over.

A final note on accuracy. My tests show that the distance to the line is within about 10 feet most of the time but might be off as much as 30 feet. You still need to use your eyes for that last boat length! This is based on the accuracy of the GPS system when using a WAAS GPS receiver. StartLine does a lot of correction to get it that close. If you do not use a WAAS or equivalent system, the errors will be about twice as much.