TurtleMobility

Package: inet.mobility.single

## TurtleMobility

simple module

A LOGO-style movement model, with the script coming from XML. It can be useful for describing random as well as deterministic scenarios.

First, a few examples.

Node will move along a square's borders:

```    <movement>
<set speed="10" angle="180"/>
<repeat n="4">
<forward d="50"/>
<turn angle="90"/>
</repeat>
</movement>
```

MassMobility (in which the node is assumed to have a mass, and cannot turn abruptly):

```    <movement>
<repeat>
<set speed="uniform(10,20)"/>
<turn angle="uniform(-30,30)"/>
<forward t="uniform(0.1,1)"/>
</repeat>
</movement>
```

Random Waypoint:

```    <movement>
<repeat>
<set speed="uniform(20,60)"/>
<moveto x="uniform(\$MINX,\$MAXX)" y="uniform(\$MINY,\$MAXY)"/>
</repeat>
</movement>
```

Commands (XML element names) are: repeat, set, forward, turn, wait, moveto, and moveby.

Accepted attributes:

• repeat: n (optional)
• set: x, y, speed, angle, borderPolicy (all optional)
• forward: d, t (at last one of them must be present)
• turn: angle (required)
• wait: t (required)
• moveto: x, y, t (all optional)
• moveby: x, y, t (all optional)

Attribute values can be literal numbers (e.g. x="100"), or any distribution accepted in omnetpp.ini (e.g. speed="uniform(10,20)"). A new value will be chosen each time the statement is executed. The \$MINX, \$MAXX, \$MINY and \$MAXY strings will be substituted with the limits of constraint area, respectively.

t is time interval, calculated from the end of the previous movement. x, y are absolute coordinates with <set> and <moveto>, and relative with <moveby>. angle is clockwise in degrees, with 0 pointing west. d is distance in meters (speed is m/s).

borderPolicy controls what happens when a node reaches the edge of the constraint area, and can take one of the values "reflect", "wrap", "placerandomly". In the first case, the node reflects off the wall; with "wrap", it'll come in on the other side (torus); and with "placerandomly", it will be placed at a random position on the constraint area.

In addition to the node position, the module maintains two interval variables, 'speed' and 'angle', which can be adjusted by <set> and <turn>. The <forward> statement, if only t or d is given, uses the speed variable. If you specify d and t together, that determines speed as well, so the speed variable will be ignored completely.

Likewise, <moveto> and <moveby> will ignore the angle variable, and will only use the speed variable if the t attribute is omitted.

If the repeat count n is omitted for the <repeat> statement, that means an infinite loop.

You can find the DTD with the sources: TurtleMobility.dtd.

Author: Andras Varga

### Inheritance diagram

The following diagram shows inheritance relationships for this type. Unresolved types are missing from the diagram.

### Extends

Name Type Description
MovingMobilityBase simple module

Abstract base module for mobility models.

### Parameters

Name Type Default value Description
coordinateSystemModule string ""

module path of the geographic coordinate system module

visualizeMobility bool true

false means this mobility module does no visualization

visualRepresentation string "^"

determines the module that is moved by this mobility

constraintAreaMinX double -1m/0

min x position of the constraint area, unconstrained by default (negative infinity)

constraintAreaMinY double -1m/0

min y position of the constraint area, unconstrained by default (negative infinity)

constraintAreaMinZ double -1m/0

min z position of the constraint area, unconstrained by default (negative infinity)

constraintAreaMaxX double 1m/0

max x position of the constraint area, unconstrained by default (positive infinity)

constraintAreaMaxY double 1m/0

max y position of the constraint area, unconstrained by default (positive infinity)

constraintAreaMaxZ double 1m/0

max z position of the constraint area, unconstrained by default (positive infinity)

updateInterval double 0.1s

the simulation time interval used to regularly signal mobility state changes and update the display

turtleScript xml

describes the movement

### Properties

Name Value Description
display i=block/cogwheel
class TurtleMobility

### Signals

Name Type Unit
mobilityStateChanged inet::MobilityBase

### Source code

```//
// A LOGO-style movement model, with the script coming from XML. It can be
// useful for describing random as well as deterministic scenarios.
//
// First, a few examples.
//
// Node will move along a square's borders:
//
// <pre><nohtml>
//     <movement>
//         <set speed="10" angle="180"/>
//         <repeat n="4">
//             <forward d="50"/>
//             <turn angle="90"/>
//         </repeat>
//     </movement>
// </nohtml></pre>
//
// ~MassMobility (in which the node is assumed to have a mass, and cannot turn
// abruptly):
//
// <pre><nohtml>
//     <movement>
//         <repeat>
//             <set speed="uniform(10,20)"/>
//             <turn angle="uniform(-30,30)"/>
//             <forward t="uniform(0.1,1)"/>
//         </repeat>
//     </movement>
// </nohtml></pre>
//
// Random Waypoint:
//
// <pre><nohtml>
//     <movement>
//         <repeat>
//             <set speed="uniform(20,60)"/>
//             <moveto x="uniform(\$MINX,\$MAXX)" y="uniform(\$MINY,\$MAXY)"/>
//         </repeat>
//     </movement>
// </nohtml></pre>
//
// Commands (XML element names) are: repeat, set, forward, turn, wait,
// moveto, and moveby.
//
// Accepted attributes:
//    - repeat: n (optional)
//    - set: x, y, speed, angle, borderPolicy (all optional)
//    - forward: d, t (at last one of them must be present)
//    - turn: angle (required)
//    - wait: t (required)
//    - moveto: x, y, t (all optional)
//    - moveby: x, y, t (all optional)
//
// Attribute values can be literal numbers (e.g. x="100"), or any
// distribution accepted in omnetpp.ini (e.g. speed="uniform(10,20)").
// A new value will be chosen each time the statement is executed.
// The \$MINX, \$MAXX, \$MINY and \$MAXY strings will be substituted with the
// limits of constraint area, respectively.
//
// t is time interval, calculated from the end of the previous movement.
// x, y are absolute coordinates with <set> and <moveto>, and relative
// with <moveby>. angle is clockwise in degrees, with 0 pointing west.
// d is distance in meters (speed is m/s).
//
// borderPolicy controls what happens when a node reaches the edge of the
// constraint area, and can take one of the values "reflect", "wrap",
// "placerandomly". In the first case, the node reflects off the wall;
// with "wrap", it'll come in on the other side (torus); and with
// "placerandomly", it will be placed at a random position on the
// constraint area.
//
// In addition to the node position, the module maintains two interval variables,
// 'speed' and 'angle', which can be adjusted by <set> and <turn>.
// The <forward> statement, if only t or d is given, uses the speed variable.
// If you specify d and t together, that determines speed as well,
// so the speed variable will be ignored completely.
//
// Likewise, <moveto> and <moveby> will ignore the angle variable,
// and will only use the speed variable if the t attribute is omitted.
//
// If the repeat count n is omitted for the <repeat> statement, that
// means an infinite loop.
//
//
//
// You can find the DTD with the sources: TurtleMobility.dtd.
//
// @author Andras Varga
//
simple TurtleMobility extends MovingMobilityBase
{
parameters:
xml turtleScript; // describes the movement
@class(TurtleMobility);
}
```
File: src/inet/mobility/single/TurtleMobility.ned