Main Content

show

Visualize path segment

Description

example

show(pathSeg) plots the path segment with start and goal positions and their headings.

show(pathSeg,Name,Value) also specifies Name,Value pairs to control display settings.

Examples

collapse all

Create a dubinsConnection object.

dubConnObj = dubinsConnection;

Define start and goal poses as [x y theta] vectors.

startPose = [0 0 0];
goalPose = [1 1 pi];

Calculate a valid path segment to connect the poses.

[pathSegObj, pathCosts] = connect(dubConnObj,startPose,goalPose);

Show the generated path.

show(pathSegObj{1})

Figure contains an axes object. The axes object contains 12 objects of type line, scatter. These objects represent Path, Start Position, Goal Position.

Create a reedsSheppConnection object.

reedsConnObj = reedsSheppConnection;

Define start and goal poses as [x y theta] vectors.

startPose = [0 0 0];
goalPose = [1 1 pi];

Calculate a valid path segment to connect the poses.

[pathSegObj,pathCosts] = connect(reedsConnObj,startPose,goalPose);

Show the generated path. Notice the direction of the turns.

show(pathSegObj{1})

Figure contains an axes object. The axes object contains 13 objects of type line, scatter. These objects represent Forward Path, Reverse Path, Start Position, Goal Position.

pathSegObj{1}.MotionTypes
ans = 1x5 cell
    {'L'}    {'R'}    {'L'}    {'N'}    {'N'}

pathSegObj{1}.MotionDirections
ans = 1×5

     1    -1     1     1     1

Disable this specific motion sequence in a new connection object. Reduce the MinTurningRadius if the robot is more maneuverable. Increase the reverse cost to reduce the likelihood of reverse directions being used. Connect the poses again to get a different path.

reedsConnObj = reedsSheppConnection('DisabledPathTypes',{'LpRnLp'});
reedsConnObj.MinTurningRadius = 0.5;
reedsConnObj.ReverseCost = 5;

[pathSegObj,pathCosts] = connect(reedsConnObj,startPose,goalPose);
pathSegObj{1}.MotionTypes
ans = 1x5 cell
    {'L'}    {'S'}    {'L'}    {'N'}    {'N'}

show(pathSegObj{1})
xlim([0 1.5])
ylim([0 1.5])

Figure contains an axes object. The axes object contains 10 objects of type line, scatter. These objects represent Forward Path, Start Position, Goal Position.

Create a dubinsConnection object.

dubConnObj = dubinsConnection;

Define start and goal poses as [x y theta] vectors.

startPose = [0 0 0];
goalPose = [1 1 pi];

Calculate a valid path segment to connect the poses.

[pathSegObj,pathCosts] = connect(dubConnObj,startPose,goalPose);

Show the generated path.

show(pathSegObj{1})

Figure contains an axes object. The axes object contains 12 objects of type line, scatter. These objects represent Path, Start Position, Goal Position.

Interpolate poses along the path. Get a pose every 0.2 meters, including the transitions between turns.

length = pathSegObj{1}.Length;
poses = interpolate(pathSegObj{1},0:0.2:length)
poses = 32×3

         0         0         0
    0.1987   -0.0199    6.0832
    0.3894   -0.0789    5.8832
    0.5646   -0.1747    5.6832
    0.7174   -0.3033    5.4832
    0.8309   -0.4436    5.3024
    0.8418   -0.4595    5.3216
    0.9718   -0.6110    5.5216
    1.1293   -0.7337    5.7216
    1.3081   -0.8226    5.9216
      ⋮

Use the quiver function to plot these poses.

quiver(poses(:,1),poses(:,2),cos(poses(:,3)),sin(poses(:,3)),0.5)

Figure contains an axes object. The axes object contains an object of type quiver.

Input Arguments

collapse all

Path segment, specified as a dubinsPathSegment or reedsSheppPathSegment object.

Name-Value Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: 'Headings',{'transitions'}

Axes to plot path onto, specified as an Axes handle.

Heading angles to display, specified as a cell array of character vector or string scalars. Options are any combination of 'start','goal', and 'transitions'. To disable all heading displays, specify {''}.

Positions to display, specified as 'both', 'start', 'goal', or 'none'. The start position is marked with green, and the goal position is marked with red.

Length of heading, specified as positive numeric scalar. By default the value is calculated according to the x- and y-axis limits of the plot.

Data Types: double

Introduced in R2019b