Working with Routes

This document is part of a manual that covers the complete operation of a Garmin handheld receiver. The full manual is copyrighted by Dale DePriest

Contents

• Introduction
• Creating a route
• Using a route
• Editing a route
• Unusual uses for routes

A route is a collection of waypoints that are related in a way that permits you to use them to follow a prescribed course. Each section of the course is called a leg of the route. Generally on the Garmin units you can create a route with 2 to 30 waypoints (1 to 29 legs) and the unit will keep track of up to 20 such routes. The etrex, emap, and 76 have up to 50 waypoints in a route. The etrex supports one route, the etrex summit supports 20 and the emap supports 50 as does the 76. There are a number of things that can be done with routes, but the most common is to use a route to guide you to a destination.

Actually many people don't see the need for routes at all. If you need to go to a destination that exists in your list of waypoints you can simply use the "goto" command to guide you to the destination. Under these conditions you have created a route of two points, where you are located now and a target destination. Once you have initiated a goto the Garmin navigation screens will point you toward the destination and the map screen will draw a line from your present location to the target location. Of course, you may not be able to head directly toward the destination since there may be obstacles in the way so you must navigate by working your way toward the destination while moving around whatever obstacles you may encounter. This works surprisingly well even when driving in a car where you use the compass navigation screen to keep the destination objective in mind while traveling down the road. A feature of the "goto" command, on units equipped with this key, is that you can re-initiate it at any time by hitting the "goto" key again and hitting "enter" to repeat the same destination. The gps will recompute a line from the current location to the destination. The emap always recomputes from the present location while the etrex has an option on the local menu so that it can work either way. To force a re-evaluation on the etrex you will need to switch it to current bearing or re-initiate the goto. The gps will keep an updated calculation of the airline distance to the destination and will compute your probable arrival time based on your current speed and heading.

The newest units have no goto key so on these units you would use an object oriented approach, that is, find the waypoint and then the waypoint page will provide a goto button. The emap and other newer mapping units also support direct goto's to map objects without the need to create a waypoint. Use the cursor keys to highlight the object and then press enter to get information on the object. A goto button will be on the menu. The emap also uses a slightly different method of computing your probable arrival time. Instead of using the current speed and heading and computing a velocity made good it use the most recent sustained velocity. Thus it does not change the value rapidly nor does it respond to acceleration or even stopping. The value will be changed when you achieve a new sustained velocity. You can cause the value to be recomputed on this unit by using the stop navigation/resume navigation command sequence.

Many times, however, a closer approximation to the path being followed can be a big help. A route with intermediate waypoints can alert you to turns in the route to keep you from getting lost. Further, an approximation of the actual course will permit better estimates as to distance and arrival times. These intermediate waypoints may also indicate probable stopping points such a rest areas or refuel points. The gps will estimate time and distance to these waypoints as well as time and distance to the final destination. This estimate is based on your current speed and an expectation that you will be following the route vectors.

Creating A Route

1. Be sure that the tracklog feature is on. The tracklog feature can be reached either from the map page menu under Track Setup or from the main menu page under track log. On some units you will have a choice to collect data using a wrap mode or a fill mode. This is only important if you are likely to exceed the capacity of the track log on your trip. Use wrap mode if the data closest to your destination is most important and fill mode if the data most closest to the starting point is most important or if you wish to insure that all data is available. For trackback purposes the automatic tracklog does the best job of collecting data but use timed mode if you must insure that the log does not overflow. Be sure and clear the log at the start of the trip.
2. Drive to your destination. If your tracklog is set to fill and you happen to fill it up you will get a warning message. At this point you could generate a backtrack and then clear the log and start it up again if you wish to have a complete record of the trip. (On the G-III you can also save the tracklog in a secondary saved tracklog.) You can also monitor the tracklog even if you don't have the warning and decide to generate a backtrack route from any point you feel is significant. A trackback route like any other route can have, at most, 30 waypoints in them. If the route is really complicated you may feel that 30 waypoints is too few when the tracklog is full. Under these conditions you will need to generate the trackback earlier. Note that you can reinitialize the tracklog once while the trackback route is saved in the active route log. Doing this a second time will clear the earlier route without warning so be sure and save it first.
3. Once you have reached your destination, or prior to beginning the return trip, you simply activate the trackback feature to create the the return route. All of the routing features and navigation features of the gps will be available to help you return to the start of your trip. The command location for enabling a trackback is different for the different units. On older units you can find it on the same menu that you found the original track log. On newer units it can be found at the bottom of the goto menu that is reached by pressing the "goto" key.

Invoking the Trackback command causes your gps to analyze the tracklog and look for the most significant turns in the log. It will then reduce the number of turns to a maximum that will not exceed the route capacity of 30 waypoints. (Actually I have never seen it go beyond 29.) Trackback routes work by creating so called temporary waypoints. These are like the other waypoints and use up waypoint memory just like other waypoints do. They have a special name that begins with a T and is followed by a unique number and if your unit supports icons they will have a special icon assigned. If you waypoint memory is full then the trackback command will warn you and use the closest match in existing waypoints to create the backtrack. On some units initiating a trackback will erase all temporary that are not part of a route however, on most units temporary waypoints are just as permanent as regular waypoints. The Garmin III says that if it runs out of waypoints in the database if will start removing temporary waypoints that are not part of a route. Erasing the route created by a trackback will not erase the waypoints themselves.

If you have a G-III family unit with multiple track logs you can also create a backtrack route using one of the saved tracklogs. Perform the same steps to select a backtrack and then select the menu item saved logs and follow the messages to select the saved log of your choice.

Creating a route manually

The advantages of creating a route this way are that you can pick exactly the points where decisions need to be made. Also the waypoints you make will be tagged with the time you made them which can be useful it determining average speed and other trip history data. Note the newest units that store altitude with the waypoint do not have comments or store the time the waypoint was created.

Creating a route from a paper map

If you have a scaled map but no grid or would rather not enter all of those coordinate then you can use the following technique to create a route.

1. You must have an actual coordinate for the first point in the route. You can create this first waypoint from a map containing the coordinates or by actually visiting the location. If you only have coordinates for the corner of the map then you can create a temporary waypoint using that corner that will be removed later. Create this waypoint. (See the chapter on waypoints to create this if you don't know how.)
2. Select the route menu item from the main menu and create a new route page.

   On the G-III family you select a new route page by picking it off the local menu. You could use the active route page for this if you wish since it is always present and is designed to be used for planning purposes. The emap and etrex can only reach the route page from the main menu.

   On other Garmin units - To select a new route highlight the route number, hit enter, and use the up/down arrow keys to find a number that is not in use. Hit enter again and move to the first route point entry.

3. Hit enter on the blank routepoint line. You will be allowed to enter the name for the first routepoint, pick the name of the waypoint you entered above. (Or use the local menu if you have a menu key.)
4. Bring up the route menu again and select review waypoint on this waypoint name. This will bring up the waypoint editing screen with the waypoint selected.
5. Select NEW and fill in the new name you want. Fill in the REF: field with the name of the earlier waypoint. Using a ruler and protractor enter the distance and bearing under the reference keyword. You will have to scale the map to real numbers based on your current unit preferences. A calculator or set of dividers can be of use here. Selecting DONE will create this new waypoint as a projection of the information of the earlier point.
6. Repeat these steps for each waypoint you wish to create for the route.

Entering routes from the map screen

Any receiver that supports panning can use a displayed tracklog to build a route manually. Simply pan to the points in the tracklog where you want the route point to appear and press the enter key to make a waypoint. Then the waypoints can be turned into a route. This can be automated to some degree by using the active route page and the viewmap facility to add the waypoints after the first one is generated. Each time you go back from the view map you will be on the route page. For example the a route can be added to the etrex vista using mappoints as follows:

1. Select a starting waypoint and then use the local menu to add it to a new route.
2. You can bring up the new route you just created the first point for and add a routepoint, this will bring up the find menu.
3. Select a waypoint and then show the map and scroll to any place on the map to highlight a map point. Press the click stick.
4. Ok to add it and repeat the process.

Other techniques

1. Select a new empty route from the route form.
2. Move to the first empty routepoint line and hit enter.
3. Toggle in the routepoint name (an existing waypoint) and hit enter (or select from the find menu).
4. Repeat until the last routepoint name is entered.

Another way to build a route is to look at the map display and create waypoints directly on the map either using a tracklog, a displayed map (for units having maps), or using a database of cities or buoys. If you scroll the map screen you can use the MARK key to mark waypoints from the map display. If you select a database object on the screen you can use the menu to turn it into a waypoint for use in a route. Otherwise this technique is similar to the manual technique. On mapping receivers creating a route using the map display is even easier. You select New Route from the route menu and then select map display. You can use existing or new routes and they will automatically be added to the route you are building.

The emap, etrex units, and 76 series can build route using map objects as well. Generally you would start on the route page and then select the object using the find menu for inclusion in the route. Any of the objects can be used and you are not required to convert them into waypoints to use them in a route. If you wish to convert them you can use the showmap command to view them on a map and then a local menu will permit converting them to an actual waypoint. This might be desirable in the emap if the object is on a cartridge that is not always present. If you wish to select the map object graphically then begin on the route page, use find to get to an object that is close to the one you want, and then use showmap to view this object. Once the map is on the screen you can use the arrow keys to select a different object. Once you hit esc to return to the route screen the new object will be the one used. Note that map objects, called mappoints, do not come out of the 500 waypoint database unless you choose to convert them to waypoints. You can have up to 1000 mappoints in use in routes and tracks.

The III Pilot can use database objects from the Jeppesen database as part of a route or as the direct destination. Holding down the goto key on this unit will bring up the Jeppesen database objects similar to the find key on the emap.

The 76 can use points in its city database or navaid database for routes creation.

Naming the route

If you only work with backtrack routes (on units that use routes to do backtrack) then using routes is really easy. You create a route when you need it. The route page will automatically appear in the rotation (G-III family has it in the rotation always) and you use the route until arriving back at the start point. You then clear the route or perhaps just overwrite it with the next backtrack.

Other routes are almost as easy. Select the ROUTE command from the main menu and then select the route number or name. Move to the route you want to activate, select it and then move to the activate (ACT) entry and select (use the local menu on the G-III). Routes can also be reversed using the INV, invert, entry so that the same route can be used to go either direction. (See below for etrex commands.)

On units with numbered routes the active route page is really just route number 0 so when you activate a route the route you chose is copied to route 0 overwriting whatever used to be there. In all other respects route 0 behaves like any other route. Units that use named routes will allow you to select the route from a list and do not have a notion of a special route 0.

Each time you activate a route it will overwrite whatever route might be present on the active route page. If you want to save an active route you must copy it to another route number before overwriting or clearing it. To copy the active route perform the following steps.

1. Bring up the route command from the main menu page.
2. Select route 0 and then select "COPY TO" by pressing enter on the underscore next to the command. (On the G-III select the TRACKBACK route and use the copy command from the menu.)
3. Use the up/down arrow keys to select an empty route number and
4. Press enter to perform the copy. (Route 0 remains unchanged.)

Whatever method you use to activate a route the gps unit will use your current location to compute an entry point into the route. It looks at each leg of the route and then projects it into a line and computes a direction that will intersect the closest line. For this reason it will never select the first waypoint in a route as the target for a leg. The navigation screens and map screen will reflect the fact that a route is being used. The map screen will display the route and two new numeric entries will appear identify the bearing and distance to the nearest routepoint on some receivers. Similarly the navigation screens will indicate this data as well as the name of the next waypoint. (See the navigation chapter for more information on using navigation screens with routes.) In addition you will have the route displayed on the active route page. It looks something like the one below.

  ACTIVE ROUTE       or   HOME-GAS     ROUTE
-----------------         -----------  PLAN
HOME TO GAS               WAYPNT <DST>
-----------------         HOME   _.__
WAYPNT  ETE  DST          LAKE   2.18
HOME   __:__ _.__         TRAIL  4.05
LAKE   33:04 2.18         GAS    7.24   TOTAL
TRAIL  01:01 4.05         ______ _.__   7.24
GAS    01:50 7.24
______ __:__ _.__         (commands are on a
______ __:__ _.__         local menu)
______ __:__ _.__
______ __:__ _.__
-----------------
CLEAR? INVERT?

In the example above the field marked ETE is actually customizable. It can be toggled by selecting it among three choices. ETE displays the estimated time enroute given the current speed. You can also choose ETA which will display the Estimated time of arrival to the next waypoint (Scroll to the last waypoint in the route to see the ETA for the entire route.) or DTK which is the Desired Track (Bearing) to reach the next waypoint. The DST field shows the cumulative vector distance to the waypoints computed in your current units and assuming you are actually following the route.

The G-III family shows only one entry but the choice for what that entry displays includes much more information. Since this is also a planning screen, in addition to the 4 entries above, you can check the to see if there is sunlight (sunrise, sunset times) at each of the waypoints, fuel usage to that point, fuel usage for each leg of the route, distance between each waypoint, and estimated travel time to that point.

While following an active route the gps will automatically sense the next leg of the route and switch to guide you on the new leg. This is done mathematically by computing when you cross a line that is projected halfway between the course you are on now and the course for the next leg. You don't actually have to reach the exact waypoint for the switch to occur. Please study the figure at the left. Consider that you are following a route to get from point A to point C. The leg AB and leg BC that are part of this route with a common waypoint at point B. The unit projects a line through points BD that bisects this angle. Once the gps detects that you have crossed this line it will switch from navigating to point B to navigating to point C.

If you have alarms turned on and arrival alarms set to automatic you will receive a warning when you get within one minute (15 seconds on the etrex and variable based on speed on the emap) of each waypoint based on your current speed toward the waypoint. On some units it is possible to have arrival alarms turned on but set to a specific distance. In this case the there will be no alarm sounded for the intermediate waypoints but the unit will still switch automatically to each new leg. Routes are turned off automatically for etrex and emap when you reach the final destination but are not turned off automatically on other units and will continue to point to the final waypoint in the route even if you drive past that point. You can clear the route by selecting the clear (CLR) command from the active route page menu. This will remove the route from the active route status but will not remove the waypoints used in the route. On the G-III family there is a deactivate command which will leave the route available on the route planning page. On the emap and etrex you can use the local menu selection "stop navigation" to do this. If you power off while stop navigation is selected then then the active route will be stopped permanently otherwise you can use the "resume navigation" to restart it on the emap.

If you intend to go back the way you came you might prefer to just invert (INV) the route rather than clearing it. This will reverse all of the waypoints for the route and compute a new entry point into the route. Inverting an active route twice is a way to force the gps to recalculate its entry point in the route which can be useful when you have left the route for a side trip and wish to return but not to the exact point that you left. The G-III family has a reactivate command on the menu that performs this function so you don't have to invert twice. The emap can use the stop/resume navigation command sequence to do this.

If you can't get the unit to aim at the correct waypoint or you wish to take a side trip you can force the unit to use a particular waypoint using the "goto" key or goto function. Setting a goto will override the current route setting and allow navigation to that waypoint. Once the waypoint is reached the route navigation will automatically continue except on the etrex model where you will have to restart the route.

Some of the Garmin units also have an activate (ACT) command on the active route page. This can be a very powerful and very dangerous command. The best way to understand how it works is to consider an example. Suppose you selected route 4 and activated it. (This copied the route to route 0 and shows it on the active route page.) It is possible to edit the route on the active route page. If you want to re-copy route 4 and reactivate it while you are navigating the active route you can select this command from the active page. If you had made any changes to the active route they will be lost. So one use of this button is to reactivate and recompute the active route. If you were to switch the route display to route 5 after activating route 4 and some time later decide to select the activate command on the active route page you will automatically switch to route 5. In this way to can easily have a route that consists of up to 60 waypoints or parts thereof. Just pick a route number, activate it, and then pick a different route number. Later when you are finished with the first route selecting this single command will start the second route and enter the route wherever you need to be in the second route.

While this feature is very powerful it can also be dangerous. If you were to have a backtrack route enabled that you haven't saved yet and accidently selected this command on the active route page you will overwrite your trackback with whatever route was last selected on the route menu. There is no warning. To prevent this you might want to ensure that the last route selected on the route page is route 0 since reactivating route 0 won't erase anything on the active route page. (If route 0 is the current route then this command will behave like the G-III reactivate command.) Taking this precaution is especially recommended if you plan to directly edit the route on the active route page.

Etrex route activation

The etrex route activation represents the newer thinking about the menu system used to activate routes. In particular the fact that the summit has no real local menu option means that all of the buttons must be on the screen and the screen won't hold many buttons. To activate a route on the Summit you must select the follow button. A second menu list will appear that permits you to choose the direction you wish to go but it does say that. Instead it offers choices of beginning and end. These are the destination choices so they are really reverse and forward and no permanent change in the route direction is made.

Etrex units with a local menu such as the local menu on the banner of the Vista contain the direction reverse on the local menu as well as other choices such as remove all, copy route, delete, calculate route area, restore defaults. The reverse command will make a permanent change in the direction of the route.

Editing A Route

Normal route editing commands are reached using the local menu or are available at the bottom of the screen for some commands in some units. Using editing commands you are able to review the contents of a waypoint, delete or insert a new waypoint, exchange one waypoint for another in the route, delete the complete route or copy the route as the starting point for another route. These editing commands are available for regular routes and for the currently active route except that you can't delete a routepoint that is currently your target destination. Deleting a routepoint from your route does not remove it from the waypoint database. To use the routepoint editing commands just use the cursor keys to move to the routepoint you want to work with and bring up the local menu (Either the menu key or the enter key depending on the unit). The choices will be displayed and will effect the current routepoint. If you already have 30 (50 on the emap and etrex) routepoints in your route then you will be unable to select the insert command otherwise selecting this command will shove all of the following waypoints down to make room for the new one.

The "copy to" command will permit you to copy the current route to a new route number (on the G-III family it is the route name with an added number). Select the route you want and then select the copy command. You will only be given choices of empty route locations. This feature is most often used when saving a backtrack route. It can also be used if you want to edit a route by beginning with an existing route. Trackback always create new routepoints if there is room in the waypoint memory. This is not efficient so you will probably want to change them for existing waypoints if part of your route covers the same ground you have used in another route. To do this easily I activate the route and then run it in the simulator mode, since I can never remember the names for these routepoints. As these double waypoints show up on the map screen I select them and note their names. I then go to the route screen and change the entry for the one I want. (You need to run the simulator or actually traverse the route to get the waypoints to appear on the screen since only the closest 9 will appear.)

Adding route points from the map screen on the G-III

1. Bring up the main menu. (Hit the MENU key twice.)
2. Select ROUTE on the MAIN MENU.
3. Select an existing route. (It must have less than 30 routepoints.) This will place you in the ROUTE PLAN screen.
4. Select SHOW MAP from the local menu.
5. On the screen you will see the Route Waypoints connected together with the Solid ACTIVE ROUTE LINE. If the ACTIVE ROUTE LINE is not showing, you either have that option turned off or are zoomed out to far.
6. Move the cursor using the rocker key until you have highlighted the ACTIVE ROUTE LINE between two waypoints. The solid line will turn to a dashed line.
7. When the solid line turns to a dashed line, press the ENTER key. The GPS will now display INS by the cursor. This puts you in the automatic insertion mode.
8. Move the cursor to where you want to insert the new waypoint. The dashed line will rubberband along with your cursor.
9. When you have the cursor where you want to place the inserted waypoint press ENTER again. The NEW MAP WAYPOINT screen will then be displayed. This allows you to change the name, symbol, etc. The word USE will be highlighted. Just hit enter if you don't want to make any changes. The waypoint will automatically be inserted in your route between the two waypoints that you had picked the line.
10. When you press ENTER on the USE option, the map will be redisplayed. Simply point to another ACTIVE ROUTE LINE and press ENTER to get the INS by the cursor. Again place the cursor where you want the waypoint and press ENTER again to insert that waypoint.

• One use for a route is to provide a crude map that will be shown on the map screen on units that don't have maps or don't have enough detail. A route might show the location of a highway giving you a visual indication to maintain orientation.
• It is also possible to use a route to indicate the approximate outline of a lake or perhaps a shoreline. This can be handy to force the display of marinas and other features that could be beyond the range of the nearest nine waypoints.
• A route could also be used simply to provide a record of somewhere that you traveled. Later when you returned home you might use your gps in simulation mode to retrace the route while having the unit hooked up to a mapping program on your computer. A mapping program will be fooled by the simulation mode into thinking you are actually working live.
• A route could be used to aid in forcing a particular orientation of the map page. Since the display on the Garmin map page is rectangular it tends to provide more information in one direction than the other. Some folks might like to force the long direction to be the favored direction for looking ahead of the current path.
  1. Create a waypoint exactly east and exactly west of your home location
  2. build a route out of these three points.
  3. Then set the map options to display DTK up and enable the route.
  4. Now the screen display will orient in general agreement with the edges of a paper map that you using and give a slight edge to seeing upcoming waypoints.
  Similarly North and South waypoints could be set if you prefer this technique to the simple 'North up' setting on the map preferences. A side benefit is that it makes it easy to always know how far you are away from home.
• A route can be used as a planning tool. While in general this statement is true of all Garmins it is particularly true for the Garmin III family. There are special features in this unit to set up average speeds and average fuel consumption and a date and time to permit estimating arrival times and important stop points based on time of day and distance for the planned trip. A few of these features can be emulated in simulation mode on other garmin units by inserting an average speed for the simulation and reviewing the information on the active route screen. All Garmin units except the basic etrex can calculate sunrise and sunset times at a target destination for planning purposes. Note that the time zone is not adjusted for this calculation.
• A route can be used to highlight a destination. For example several folks in the sci.geo.satellite-nav news group used their gps's to help them find the path of a solar eclipse. Using data provided in a magazine you can create a route of the center line of the eclipse and then just head for a point anywhere on the route. You can visually see the path of the eclipse directly on the map screen. You can even get more exotic by defining a route of the totality drawing two parallel lines with a connection at one end. A route defined this way gives you a visual indication of the location of the total eclipse and if you are using a gps with built in maps you can perhaps spot a viewing location that is a little more out of the way than the places the crowds know about.
• A route can be used to force the waypoints to appear on the map screen. Most units only display the 9 closest waypoints on the map screen (15 on the emap) and then only if they are within a fixed distance. Activating a route causes all of the route waypoints to appear in addition to the closest ones.
• A route can be used as a waypoint management tool. For example if can store a collection of waypoints of places you intend to visit on your vacation or some of your favorite fishing spots. In this case you would might never actually activate the route but just placing the waypoints in the route provides a way to easily find them as a collection and you can use goto to actually navigate to one of the locations.

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by Dale DePriest - all rights reserved.

revision