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sphereModel

Object for storing a parametric sphere model

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Description

The sphereModel object stores a parametric sphere model.

Creation

Syntax

model = sphereModel(parameters)

Description

model = sphereModel(parameters) constructs a parametric sphere model from the specified parameters. The parameters argument is a 1-by-4 numeric vector that determines the value of the Parameters property.

example

Input Arguments

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Sphere parameters, specified as a 1-by-4 vector. This input specifies the Parameters property. The four parameters [a b c d] satisfy this equation for a sphere:

(x−a)2+(y−b)2+(z−c)2=d2

Properties

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This property is read-only.

Sphere model parameters, stored as a 1-by-4 numeric vector. This property is set by the parameters input. The four parameters [a b c d] satisfy this equation for a sphere:

(x−a)2+(y−b)2+(z−c)2=d2

This property is read-only.

Center of the sphere, stored as a 1-by-3 vector of form [xc yc zc]. The elements xc,yc,zc specify the x-, y-, and z-coordinates of the center coordinates of the sphere, respectively.

This property is read-only.

Radius of the sphere, stored as a scalar value.

Object Functions

plotPlot parametric model
findPointsInModelFind points in or on surface of geometric model

Examples

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Open Live Script

Load a point cloud into the workspace.

load("object3d.mat");

Display the point cloud and label the figure.

figure
pcshow(ptCloud)
title("Detect a sphere in a point cloud")

Figure contains an axes object. The axes object with title Detect a sphere in a point cloud contains an object of type scatter.

Set the maximum point-to-sphere distance for sphere fitting to 1cm.

maxDistance = 0.01;

Set the region of interest to constrain the search.

roi = [-inf,0.5;0.2,0.4;0.1,inf];
sampleIndices = findPointsInROI(ptCloud,roi);

Detect the globe in the point cloud and extract it.

[model,inlierIndices] = pcfitsphere(ptCloud,maxDistance,SampleIndices=sampleIndices);
globe = select(ptCloud,inlierIndices);

Plot the extracted globe.

figure
pcshow(globe)
title("Globe Point Cloud")

Figure contains an axes object. The axes object with title Globe Point Cloud contains an object of type scatter.

Version History

Introduced in R2015b

See Also

Objects

Functions

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