How to find road centers of a road from a loaded map?

When we load a map using liveMap, then how we can find out the road centers?

[Sam Chak]

@Ashish Kumar Singh, What is a road center?

[Ashish Kumar Singh]

Road centers used to define a road, specified as a real-valued N-by-2 or N-by-3 matrix. Road centers determine the center line of the road at discrete points.

• If roadcenters is an N-by-2 matrix, then each matrix row represents the (x, y) coordinates of a road center. The z-coordinate of each road center is zero.
• If roadcenters is an N-by-3 matrix, then each matrix row represents the (x, y, z) coordinates of a road center.

If the first row of the matrix is the same as the last row, the road is a loop. Units are in meters.

Data Types: double

[Constantino Carlos Reyes-Aldasoro]

Can you be more specific? Add an example of what your data is, and what your expected answer would be.

[Ashish Kumar Singh]

After importing a geographical road map how can I find out the co-ordinates(mostly end coordinates) of the road imported in the map ??

Answer 1

[Anurag]

Hello Ashish

In order to find the road centre, you can use the Automated Driving Toolbox. The toolbox lets you import and work with HERE HD Live Map data and ASAM OpenDRIVE road networks.

After the map is imported, you can obtain the outer and inner road boundaries using the "roadBoundaries" function.

One of the boundaries must be flipped so that the orientation of both boundaries is the same. Once the orientation of the boundaries is the same you can use vector addition to calculate the road centres.

Refer to the example given below:

rb = roadBoundaries(scenario); 
outerBoundary = rb{1}; 
innerBoundary = rb{2}; 
outerBoundary=flipud(outerBoundary); % flip the outerBoundary so that the boundary orientations are consistent 
roadCenter=0.5*(outerBoundary+innerBoundary);

Adding MATLAB documentation links for your reference:

• https://www.mathworks.com/help/releases/R2021b/driving/index.html
• https://www.mathworks.com/help/releases/R2021b/driving/ref/drivingscenario.roadboundaries.html