updateObstacleGeometry

Update geometric properties of obstacles

Syntax

updateObstacleGeometry(capsuleListObj,obstacleIDs,geomStruct)

status = updateObstacleGeometry(capsuleListObj,obstacleIDs,geomStruct)

Description

updateObstacleGeometry(capsuleListObj,obstacleIDs,geomStruct) updates geometry parameters for the specified obstacles in the capsule list. If a specified obstacle ID does not already exist, the function adds a new obstacle with that ID to the list.

status = updateObstacleGeometry(capsuleListObj,obstacleIDs,geomStruct) returns an indicator of whether an obstacle is added, updated, or a duplicate.

Examples

Build Ego Body Paths and Check for Collisions with Obstacles

Build an ego body path and maintain obstacle states using the dynamicCapsuleList object. Visualize the states of all objects in the environment at different timestamps. Validate the path of the ego body by checking for collisions with obstacles in the environment.

Create the dynamicCapsuleList object. Extract the maximum number of steps to use as the number of time stamps for your object paths.

obsList = dynamicCapsuleList;
numSteps = obsList.MaxNumSteps;

Add Ego Body

Define an ego body by specifying the ID, geometry, and state together in a structure. The capsule geometry has a length of 3 m and radius of 1 m. Specify the state as a linear path from x = 0m to x = 100m.

egoID1 = 1;
geom = struct("Length",3,"Radius",1,"FixedTransform",eye(3));
states = linspace(0,1,obsList.MaxNumSteps)'.*[100 0 0];

egoCapsule1 = struct('ID',egoID1,'States',states,'Geometry',geom);
addEgo(obsList,egoCapsule1);

show(obsList,"TimeStep",[1:numSteps]);
ylim([-20 20])

Add Obstacles

Specify states for two obstacles that are separated from the ego body by 5 m in opposite directions on the y-axis. Assume the obstacles have the same geometry geom as the ego body.

obsState1 = states + [0 5 0];
obsState2 = states + [0 -5 0];

obsCapsule1 = struct('ID',1,'States',obsState1,'Geometry',geom);
obsCapsule2 = struct('ID',2,'States',obsState2,'Geometry',geom);

addObstacle(obsList,obsCapsule1);
addObstacle(obsList,obsCapsule2);

show(obsList,"TimeStep",[1:numSteps]);
ylim([-20 20])

Update Obstacles

Alter your obstacle locations and geometry dimensions over time. Use the previously generated structure, modify the fields, and update the obstacles using the updateObstacleGeometry and updateObstaclePose object functions. Reduces the radius of the first obstacle to 0.5 m, and change the path to move it towards the ego body.

obsCapsule1.Geometry.Radius = 0.5;

obsCapsule1.States = ...
    [linspace(0,100,numSteps)' ... % x
     linspace(5,-4,numSteps)' ... % y 
     zeros(numSteps,1)]; % theta

updateObstacleGeometry(obsList,1,obsCapsule1);
updateObstaclePose(obsList,1,obsCapsule1);

Check for Collisions

Visualize the new paths. Show where collisions between the ego body and an obstacle, which the display highlights in red. Notice that collisions between the obstacles are not checked.

show(obsList,"TimeStep",[1:numSteps],"ShowCollisions",1);
ylim([-20 20])
xlabel("X (m)")
ylabel("Y (m)")

Programmatically check for collisions by using the checkCollision object function. The function returns a vector of logical values that indicates the status of each time step. The vector is transposed for display purposes.

collisions = checkCollision(obsList)'

collisions = 1×31 logical array

   0   0   0   0   0   0   0   0   0   0   0   0   1   1   1   1   1   1   1   1   1   1   0   0   0   0   0   0   0   0   0

To validate paths with a large number of steps, use the any function on the vector of collision values.

if any(collisions)
    disp("Collision detected.")
end

Collision detected.

Update Ego Path

Specify a new path for the ego body. Visualize the paths again, displaying collisions.

egoCapsule1.States = ...
    [linspace(0,100,numSteps)' ... % x
    3*sin(linspace(0,2*pi,numSteps))' ... % y
    zeros(numSteps,1)]; % theta

updateEgoPose(obsList,1,egoCapsule1);

show(obsList,"TimeStep",[1:numSteps],"ShowCollisions",1);
ylim([-20 20])

Input Arguments

capsuleListObj — Dynamic capsule list

dynamicCapsuleList object | dynamicCapsuleList3D object

Dynamic capsule list, specified as a dynamicCapsuleList or dynamicCapsuleList3D object.

obstacleIDs — IDs of obstacles to update

vector of positive integers

IDs of obstacles to update, specified as a vector of positive integers.

geomStruct — Geometry parameters for ego bodies

structure | structure array

Geometry parameters for ego bodies, specified as a structure or structure array, where each structure contains the fields of the structure in the Geometry field of the obstacle to be updated.. The fields of this structure depend on whether you are using a dynamicCapsuleList or dynamicCapsuleList3D object.

Data Types: struct

Output Arguments

status — Result of updating obstacles

N-element column vector

Result of updating obstacles, specified as N-element column vector of ones, zeros, and negative ones. N is the number of obstacles specified in the obstacleIDs argument. Each value indicates whether the obstacle is removed (1), not found (0), or a duplicate (-1). If you specify the same obstacle ID multiple times in the obstacleIDs input argument, then all entries besides the last are marked as a duplicate.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2020b