Least-squares adjustment of Points to Cylindrical Surfaces

此工具以最小二乘方式對點雲資料進行擬合，並以圓柱體為擬合目標，求取最合適代表圓柱體的7個參數，即圓柱體坐標位置、中心線方向向量及半徑，並將參數成果轉換為圓柱體起訖點坐標。

The tool uses the least squares method to fit point cloud data to the cylindrical surface to obtain results that are most representative of the cylinder. The adjustment result includes 7 parameters including cylindrical coordinates, direction vector of cylindrical centerline, and radius. Finally, convert the parametric results to the coordinates of the start and end points of the cylinder.

*Note: This tool is suitable for cylinders whose height exceeds their radius.

This toolbox contains 6 MATLAB codes,

• 1 main program - adjustment_cylinder_with_r.m：*Input data should be in n*3 format, named "point".
• 5 calling programs -

1. pointslope_radius.m：Calculate initial approximation
2. adjust_cylinder_with_r.m：Adjustment calculation
3. plot_approximationIncrement.m：Approximate value increment and sigma change plot
4. plot_residualsdistribution.m：Residual distribution plot
5. params2endpoints.m：Convert the calculation results to the coordinates of the cylinder endpoints

cylindrical surface mathematical formula:

• Input data -
• 7 unknown parameters -

V[a,b,c] as the direction vector of the cylinder centerline

P(d,e,f) is the coordinate of the perpendicular foot from origin to the centerline of the cylinder

r for radius

Procedure

Example

• input point cloud

• approximation increment & sigma

• residuals distribution

• final reuslt

If you have any questions or suggestions or would like more details, please feel free to leave any comments below or contact me via email. Also, I would appreciate it if you could share with me your usage and feelings about this tool.

Hao-En LIN

[e-mail]