Trimble Business Center

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

I assume the UAV data was just images, or was it a scanner/LIDAR drone?

If it was just images with a point grid draped on it, which is now the pointcloud that you have in TBC, then there is no way to get decent ground information on high grass areas. The images usually have a resolution of 1 cm upwards and never will see the ground between the grass, hence the images always contain the information for top of grass, hence your cloud is top of grass.

And even if the drone had a LIDAR scanner it is difficult to retrieve ground information. We had a subcontractor fly our site with one of those and I was rather disappointed with the vegetation penetration of the scanner. With newer TBC versions we have the advanced filter option where we can filter the whole cloud for low points in a defined cell pattern, and even that doesn't always provide good enough results. It works reasonably well on flat areas but has its difficulties on steep slopes. And it also depends on how the scanner was setup, if it did scan vertically down, or on an angle.

With your V5.70 you're pretty limited. If the "Classify point cloud" didn't yield good enough data, your only other option is using the rather tedious "Create High/Low Point".

Point cloud classification is one of the things that has been improved with the updates in the last few years.

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Hi Ronny,

Thank you for your feedback.  You are right, that our point cloud data is derived from aerial photo images, so data is containing top of grass.

I have classified point clouds as building, high vegetation, low vegetation, ground, and road. Ground is still containing low vegetation.

According to your suggestion, I have used Create High/Low point. But there is shown only highest and lowest point coordinate and elevation in selected area.

You can download the data as below.

https://we.tl/t-faPqNVEEpw

I assume the UAV data was just images, or was it a scanner/LIDAR drone?

If it was just images with a point grid draped on it, which is now the pointcloud that you have in TBC, then there is no way to get decent ground information on high grass areas. The images usually have a resolution of 1 cm upwards and never will see the ground between the grass, hence the images always contain the information for top of grass, hence your cloud is top of grass.

And even if the drone had a LIDAR scanner it is difficult to retrieve ground information. We had a subcontractor fly our site with one of those and I was rather disappointed with the vegetation penetration of the scanner. With newer TBC versions we have the advanced filter option where we can filter the whole cloud for low points in a defined cell pattern, and even that doesn't always provide good enough results. It works reasonably well on flat areas but has its difficulties on steep slopes. And it also depends on how the scanner was setup, if it did scan vertically down, or on an angle.

With your V5.70 you're pretty limited. If the "Classify point cloud" didn't yield good enough data, your only other option is using the rather tedious "Create High/Low Point".

Point cloud classification is one of the things that has been improved with the updates in the last few years.

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Hi Ronny,

Thank you for your feedback.  You are right, that our point cloud data is derived from aerial photo images, so data is containing top of grass.

I have classified point clouds as building, high vegetation, low vegetation, ground, and road. Ground is still containing low vegetation.

According to your suggestion, I have used Create High/Low point. But there is shown only highest and lowest point coordinate and elevation in selected area.

You can download the data as below.

https://we.tl/t-faPqNVEEpw

I assume the UAV data was just images, or was it a scanner/LIDAR drone?

If it was just images with a point grid draped on it, which is now the pointcloud that you have in TBC, then there is no way to get decent ground information on high grass areas. The images usually have a resolution of 1 cm upwards and never will see the ground between the grass, hence the images always contain the information for top of grass, hence your cloud is top of grass.

And even if the drone had a LIDAR scanner it is difficult to retrieve ground information. We had a subcontractor fly our site with one of those and I was rather disappointed with the vegetation penetration of the scanner. With newer TBC versions we have the advanced filter option where we can filter the whole cloud for low points in a defined cell pattern, and even that doesn't always provide good enough results. It works reasonably well on flat areas but has its difficulties on steep slopes. And it also depends on how the scanner was setup, if it did scan vertically down, or on an angle.

With your V5.70 you're pretty limited. If the "Classify point cloud" didn't yield good enough data, your only other option is using the rather tedious "Create High/Low Point".

Point cloud classification is one of the things that has been improved with the updates in the last few years.

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Just seen this post,

When I had UAV data for this type of OGL surface - assuming it was good enough for a reasonable representation, I used the Point clouds>"Create CAD points from Scan points" command  and then CAD>change elevation and updated all these points by an " estimate" of the Delta ( 30-40mm in your example)

The use these points to create the surface 

Used with Caution of course depending upon the final requirements and accuracies etc.

Hi Ronny,

Thank you for your feedback.  You are right, that our point cloud data is derived from aerial photo images, so data is containing top of grass.

I have classified point clouds as building, high vegetation, low vegetation, ground, and road. Ground is still containing low vegetation.

According to your suggestion, I have used Create High/Low point. But there is shown only highest and lowest point coordinate and elevation in selected area.

You can download the data as below.

https://we.tl/t-faPqNVEEpw

I assume the UAV data was just images, or was it a scanner/LIDAR drone?

If it was just images with a point grid draped on it, which is now the pointcloud that you have in TBC, then there is no way to get decent ground information on high grass areas. The images usually have a resolution of 1 cm upwards and never will see the ground between the grass, hence the images always contain the information for top of grass, hence your cloud is top of grass.

And even if the drone had a LIDAR scanner it is difficult to retrieve ground information. We had a subcontractor fly our site with one of those and I was rather disappointed with the vegetation penetration of the scanner. With newer TBC versions we have the advanced filter option where we can filter the whole cloud for low points in a defined cell pattern, and even that doesn't always provide good enough results. It works reasonably well on flat areas but has its difficulties on steep slopes. And it also depends on how the scanner was setup, if it did scan vertically down, or on an angle.

With your V5.70 you're pretty limited. If the "Classify point cloud" didn't yield good enough data, your only other option is using the rather tedious "Create High/Low Point".

Point cloud classification is one of the things that has been improved with the updates in the last few years.

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

I had just started using point cloud data for my OG surface.  What I did was stepped away from the Point Cloud processing and went straight to creating a surface.  I would then use an MSI to drop the vegetation down about an average height.  To hard to tell which area has what height vegetation.   just a little mix and match.  The flatten surface work, you just have to do it several times if you're a picky person.  

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Hi Francisco,

Thank you. MSI is good enough idea at least.

I had just started using point cloud data for my OG surface.  What I did was stepped away from the Point Cloud processing and went straight to creating a surface.  I would then use an MSI to drop the vegetation down about an average height.  To hard to tell which area has what height vegetation.   just a little mix and match.  The flatten surface work, you just have to do it several times if you're a picky person.  

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

The first time making a surface out of Point Cloud.  I saw that the surface was spiky.  Took me a few second to remember that this is a Point Cloud and not a manual walking OG topo.  So, with not having a full Point Cloud key.  I had to use other means to take out the vegetation. 

Hope it helps.  

Hi Francisco,

Thank you. MSI is good enough idea at least.

I had just started using point cloud data for my OG surface.  What I did was stepped away from the Point Cloud processing and went straight to creating a surface.  I would then use an MSI to drop the vegetation down about an average height.  To hard to tell which area has what height vegetation.   just a little mix and match.  The flatten surface work, you just have to do it several times if you're a picky person.  

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Our point cloud processor command will.likely find ground in amongst the point cloud pretty well - if you send me a file or link yo a file I will.run it for you as a test.

Alan.sharp@rockpilesutioms.com

Alan

The first time making a surface out of Point Cloud.  I saw that the surface was spiky.  Took me a few second to remember that this is a Point Cloud and not a manual walking OG topo.  So, with not having a full Point Cloud key.  I had to use other means to take out the vegetation. 

Hope it helps.  

Hi Francisco,

Thank you. MSI is good enough idea at least.

I had just started using point cloud data for my OG surface.  What I did was stepped away from the Point Cloud processing and went straight to creating a surface.  I would then use an MSI to drop the vegetation down about an average height.  To hard to tell which area has what height vegetation.   just a little mix and match.  The flatten surface work, you just have to do it several times if you're a picky person.  

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?

Our point cloud processor command will.likely find ground in amongst the point cloud pretty well - if you send me a file or link yo a file I will.run it for you as a test.

Alan.sharp@rockpilesutioms.com

Alan

The first time making a surface out of Point Cloud.  I saw that the surface was spiky.  Took me a few second to remember that this is a Point Cloud and not a manual walking OG topo.  So, with not having a full Point Cloud key.  I had to use other means to take out the vegetation. 

Hope it helps.  

Hi Francisco,

Thank you. MSI is good enough idea at least.

I had just started using point cloud data for my OG surface.  What I did was stepped away from the Point Cloud processing and went straight to creating a surface.  I would then use an MSI to drop the vegetation down about an average height.  To hard to tell which area has what height vegetation.   just a little mix and match.  The flatten surface work, you just have to do it several times if you're a picky person.  

I have imported point clouds into TBC 5.70 , from UAV data. The site was covered with 30-40cm high grass fully. I need DTM, mean Ground surface.

For that reason I did followings:

1. Classified imported point clouds.
2. Flatten surface

For the checking  or compare heights original data and flatten surface, I have tried to export Flatten surface to CAD, but not successfully.

Please advise me better approach?