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Laser Scanning - Science topic

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We want to estimate the canopy volume of trees by 3D mapping using the LiDAR sensors. Please suggest low-cost LiDAR sensors available in India for 3D mapping.
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PhoDar (photogrammetry) or SFM (structure-from-motion) is usually cheaper than LIDAR and can also generate point clouds. I suppose what really counts is the level of accuracy that your task requires. https://www.esri.com/events/transmission-summit/~/media/A36CC282BBCA42ABB06F527A648DF5E6
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where can I found free Airborne Laser Scanning (ALS) data?
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open topography
duplin data
Toronto data+ISPRS
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Below are the few which are known to me. Which devices have you used to acquire building Point Clouds? What technology does the device use? I think many researchers are looking for choices of devices for their various projects and this post can help them to put the list on the table.
  • Ipad Pro 2020
  • Google Tango
  • ZED Cam
I am adding below the Suggested Choices by respondents:
  • Geo SLAM - ZEB Go
  • FARO Freestyle 3D hand scanner
  • Dotproduct DPI-10
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Please take a look at Dotproduct DPI-10. It uses the latest intel sensors and SLAM algorithms.
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For antimicrobial evaluation of antibiotics-releasing scaffolds against the biofilm, we have planned to perform live/dead bacterial assay to be observed under confocal laser scanning microscopy. However, if the microorganism is an obligate anaerobe, we assume that it will be difficult to use this method, as the bacterial cells may die on exposure to air during observation under confocal laser scanning microscope.
Can anyone suggest some modification of this method or any other protocol to be followed in case of such obligate anaerobes?
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Maybe you can consider the use of a natural reducing agent as oxyrase.
regards
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Observation of bacteria under a SEM or MET
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I did not understand your answer can you explain to me, please?!!
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Hello everyone, I am modeling an AM process called SLM, on which a laser scan a powder bed in order to build a part. I am currently having problem with the phase-transformation phenomena (from powder, to liquid and finally solid), since a lot of work done on the field are using different approaches and mostly of them are not in my scope (modeling crystalline micro-structure formation and liquid flow). I already have a lot of data for temperature dependent properties (thermal conductivity, heat capacity, coeff. of expansion, etc).
Since I want to account for temperature distribution and thermal strains, which method would be advisable and would be quickly to implement?
I have read about account for the solid or liquid fraction into the enthalpy formulation, but I don't know which subroutine or how to implement it. 
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It still may be a question for someone, so for phase changing regarding temperature, subroutine UMATHT should be used.
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I am trying to image and quantify bacterial cells on muscles using confocal laser scanning microscope. But I am having trouble quantifying the bacteria as the stains that I used ( live/dead staining) also stains the muscle fibres.
Can anyone recommend a stain that would only stain bacterial cells ? Thank you
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Sorry, this is a question. Does anybody outside ThermoFisher know the composition of BacLite Red and BacLite Green, and what they bind to on bacteria? There once was a time when researchers were supposed to know what chemicals they were using.
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Hello everybody
I am eager to know what is the procedure in software like Catia, Cloud Compare, Geomagic or etc, that remove noise from Point Clouds(PCs); especially when the PCs does not contain RGB or intensity information and it just contains 3-D coordinates of points. (e.g.PCs are obtained from laser scanner. )
Thanks in advance
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Hi Elnaz,
From your listed software, I'm most familiar with CloudCompare. I like it because it's quite "open" as opposed to (some) commercial PC editing software, not to mention quite powerful as well. As far as I undertand it, CC's noise filter uses an SOR (Statistical Outlier Removal") based algorithm. Essentially it computes a local plane using a neighbourhood of points, and then tests the Euclidean distance of each neighbouring point against this local plane. The point gets deleted if this distance is farther than the set threshold value.
If I remember correctly CC also has an implementation of the "pure" SOR algorithm in which the point's Euclidean distance is directly taken into account instead of the distance towards the local plane.
Hope this helps, and in any case I encourage you to join the CC forum (https://www.cloudcompare.org/forum/) and also the CC wiki (https://www.cloudcompare.org/doc/wiki). They're very useful resources and many questions are answered readily by the community.
best,
arnadi
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3D Laser scanning (also known as LiDAR – Light Detection And Ranging) combines a laser rangefinder with controlled steering of laser beams
Building Information Modeling (BIM) is an intelligent 3D model-based process that gives architecture, engineering, and construction (AEC) professionals the insight and tools to more efficiently plan, design, construct, and manage buildings and infrastructure.
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I agree with you, so the operator must have significant experience and skill in use from the start
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Please see question above. Thanks for your response.
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Hi Bharat,
In this thesis we use dense point clouds in characterizing forest structural components. So far we have applied point clouds from terrestrial laser scanning (TLS) since it provides detailed digitization of horizontal forest structure (standing trees) as well as forest floor (downed dead wood). Considering the hemispherical scanning geometry, it could be helpful to use dense aerial point clouds to better characterize the upper parts of forest canopy. So if airborne laser scanning data is used in this thesis, it is used combined with TLS data.
You can find the substudies of my thesis in my RG profile. The full thesis will be an open access publication.
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Dear experts
I have a laser scan from 1M barrel reservoir tank which was in service for 20 years. This led to some spatial dislocation in some points of the tank which demands FEM analysis for the sake of FFS (Fit For Service). Therefore, I have to define spatial displacement for the tank which leads to stress. Then, I want to put the liquid inside and see if the tank can tolerate the pressure or not!
now the question is here:
How can I define the new location of the nodes?
Thanks a Million
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while working on distortion simulation of SLM process in Simufact additive i figure out that there is no way to relate the scanning pattern and laser power and laser scanning speed in the software package , how can i incorporate these among the simufact additive simulation?
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This type of features are not available in Simufact additive. If you want to consider the effects of laser parameters like laser power, laser speed, absorption coefficient etc.. for FEM simulation ,then go for GENOA 3DP tool from AlphaSTAR.
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We have deposited amorphous germanium thin films on silicon using evaporation. This was followed by pulsed laser annealing using Nd: YaG laser. Above threshold intensity, it was observed that the amorphous germanium recrystallizes as crystalline germanium. However surface ripples and a pattern of lines was observed on the surface that were aligned 55 degrees to the laser scan direction.
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I suppose that shevron pattern in recrystallized germaium pattern results due to the used laser beam configuration for annealing when an interference of incident and reflected light can take place. It is possible to change the linearly polarized beam of Nd-YAG by circular polarized one to remove the shevron pattern or at least to deacrease that contribution.
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I am working on terrestrial LiDAR modelling and simulation, and I was wondering how to prepare the correct model of LiDAR rotation. I don't understand how laser scanning pattern looks like. I know that most of the 3D sensor has 360 degree horizontal FOV and about 27 degree vertical FOV but I don't know how to connect these two things. Based on pulse rate and rotation rate I calculated degree between pulses but only in XY plane (horizontal scanning). How to add also vertical scanning? Could you give me some examples of scanning pattern and how to simulate LiDAR scanning based on LiDAR's parameters?
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Ok. I did a quick search and found this:
There is a description of the Velodyne Sensor. There are 64 lasers. Each is aiming in an individual vertical direction. They span the entire vertical field of view from +2° to -24.9° and are rotating as one unit around the vertical sensor axis. The exact scan pattern depends on the triggering of these lasers and internal calculations within the device (according to its calibration). I would assume one get a more or less straight vertical line of 64 points in every horizontal direction. Please verify it.
Hope the paper helps understanding the construction of this sensor better.
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Hello,
I am searching laser scan data for a glacier. Knows someone a source or is willing to share his data?
It will not be used for papers, lecture or similiar things.
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Carsten Hayduk here there are some useful websites which publish free LiDAR points
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i need the exact protocol for preparing the rhodamine B dye
to concentration of 0.1% and the quanitity needed for mixing 0.1% of rhodamine B dye to root canal sealer to examine it under conofocal laser scanning microscope (NIkon,Japan)
also is the dye altering the flow and setting time of the root canal sealer ?
this is all information i have about Rhodamine B dye
Rhodamine B from sigma aldrich
≥95% (HPLC)
Synonym: Basic Violet 10, Brilliant Pink B, Rhodamine O, Tetraethylrhodamine
Formula: C28H31ClN2O3
mp  210-211 (dec.)(lit.) solubility  H2O: 1 mg/mL absorption  extinction/542-554 nm, methanol 104500-115800
and i will use Sure Seal bioceramic root canal sealer from Sure Dent, Korea
and AH Plus from Dentsply
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Dear Dina,
It seems that you are not familiar with the posting of a R.G. Question! Why?
Rhodamine B : (It is a trivial name) !
At first you must give the counter anion of the rhodamine B dye in your question.
P.e. Rhodamine B Chloride (see added file) or isothiocyanate (see link) :
How to cite this URL: Ravi S V, Nageswar R, Swapna H, Sreekant P, Ranjith M, Mahidhar S. Epiphany sealer penetration into dentinal tubules: Confocal laser scanning microscopic study. J Conserv Dent [serial online] 2014 [cited 2018 Apr 12];17:179-82. Available from: http://www.jcd.org.in/text.asp?2014/17/2/179/128056
and define your root canal sealer (see link):
we, answerers, need these infos for help you in your research.
Thank you in advance.
JRG
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Can you give me a suggestion, where CLSM is needed to be used and not AFM and vice-versa?
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Talking about biological samples, CLSM gives the distribution of fluorescent-labeled proteins (or lipids and nucleic acids) and compartments inside the cell or at its surface. Functional probes can be used to measure intracellular pH, calcium concentration.
AFM gives physical measurements at the surface of the cell (topology, elasticity, viscosity...), but you can also get much deeper information like seeing the cytoskeleton or hard intracellular compartments through the plasma membrane. It is also possible to bind proteins at the tip of the cantilever to measure adhesion at the plasma membrane (ligand-receptor).
Finally, why used AFM instead of CLSM? It is also possible to do correlative microscopy, looking the same sample at the same time, with an AFM microscope coupled to an inverted CLSM microscope on fixed or live cells.
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Hello everyone,
I am involved in a project for the measuring of a mold internal volume.
It is divided in two parts and we want to find the capacity of the closed.
In order to do this we actually scan the two components with laser scanning and obtain the internal volume using a software .
We are looking for high precision method in order to compare our measure with a "reference", more precise, one.
Do you have any idea
Thank you in advance.
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Hi,
You can calculate the volume of mold scanned point cloud converting to surface model as a convex mesh model.
CloudCompare software can make this task.
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2 or 3 dimensional laser scanning are mostly done using photo-detectors to collect the reflected light and then using detection and plotting techniques. What are the most conventional or suitable photo-detectors?
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@AL Timimi Zahra
Thank you very much for the detailed answer and link.
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Hi,
Is it possible to have different point densities within a point cloud file of a large area? If so, which parameters play role in it?
Also, does it matter if the point cloud is created from image photogrammetry or airborne laser scanning (ALS)?
Thanks,
Mohammad
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Hi,
Thank you all for your answers.
all the best,
Mohammad
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Dear researchers
I have been using frontal lobe slice of 3–5 mo. old mice with its thickness of 300μm for intracellular Ca2+ measurement over confocal laser-scanning microscope [Zeiss LSM 700.] Fluorophore of choice is Indo 1-AM as its capability to penetrate cell membrane through bath loading (Tank et al. 1992).
I design protocol of loading is as follows: slice incubated in 1ml Ca2+-free ACSF (5μM Indo 1-AM) at 37ºC for 30 mins, subsequently, washed gently with 3ml of the same solution. The slice carbogenized throughout the process. 
I gain, however, very weak fluoresced spots throughout the slice in ocular observation but no signal detected in the software (as in the figure.) I am unsure the laser (405nm) is incapable of penetrating with the thickness employed.
Any suggestions are welcomed and appreciated.
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Dear Harrie
Thanks for the suggestion. I am intrigued with "do a dynamic switching" and given the microscope has only four laser wavelength of 405, 488, 555, and 639nm; what strategies do I have to take to perform it?
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My sample is spherical shape silica gel. Every time I scan, it drifted. But for my research I need same area scan for several times. then I want to analyse the differences. Detail of my scanning:
equipment: SPM-9700
Scan area 5 mircro by 5 micro
Operating mode: tapping
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It seems quite challenging, the highest magnification of optical microscopes is close to the one of AFMs. The problem is how to make marking on the sample and it depends on what is allowed to work on the surface. I think scratching by hand knife or diamond pen is a good choice if it's allowed. How?
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Simulating a moving laser for Laser Sintering process
I have used local cylindrical co ordinate system for locating center of laser on powder bed.
However the energy distribution in laser spot depends upon distance of node from the center of laser spot.
for every load step I need to calculate distance of each node from center and the compare it with laser dimension for application of heat
Can any body write a sample code for this purpose or any hint for how to do this?(any other approach is also welcome)
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I am looking at understanding the way intensity data is collected and processed by the GLS-2000 scanner. From my understanding of intensity, as a representation of target reflectance, the value for intensity should decrease with the increase in distance and similarly with the increase in incidence angle.
So at 10m you might expect to have a higher intensity value than at 30m because more of the energy from the emitted laser pulse has returned to the scanner at 10m, and at 30m the value would be lower as the laser has lost power over the increased distance. Similarly with increasing angles less laser light is reflected back so the value for intensity decreases as the angle increases.
This has proven true in my testing with the GLS-2000 in the case of increasing angles. But it is not the case with increasing range. Which is what I want to better understand.
Do you know why it would be the case that the intensity values are higher at greater distances? Is the scanner performing some sort of scaling or normalization of the intensity data? I know that some instruments have automatic gain control and other such processes that can alter the intensity values. Do you know if the GLS-2000 scanner does anything like this?
Similarly I know that some software packages (like AutoDesk ReCap, and Trimble RealWorks) perform their own normalization and corrections to intensity. I am using Scan Master to process my data. Do you know if Scan Master is performing additional scaling or changes to intensity?
And is there any way that I can look at or interrogate the raw data from the scanner before bringing it into Scan Master? I have tried looking at the raw data but it is all in code that I don't understand.
Answers to any of these questions would be appreciated.
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Good paper. 
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In your opinion what would be the optimum optical scanner for elliptical scanning trajectories (general elliptical, i.e. from line to circular in different sizes).
Which current solutions would you suggest for compact and fast response scanners (1KHz) other than e.g. classical salvo scanners?
Thank you in advance.
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Excellent, thank you very much
I know that glavos do well, but are not as compact as I would Need
AO deflectors, I have only used them as attenuators (AOM) or pulse pickers, but never as true steering System.
I am a bit concerned of the Degradation of optical Quality.
I was originally thinking of compact Risley prisms Scanners, but cannot find any manufacturer for those.
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I am using the Topcon GLS-2000 laser scanner. The recorded intensity values from this instrument do not follow the typical trends of intensity. Whereby intensity should decrease as range to the target increases.
In the case of the Topcon GLS-2000 laser scanner the intensity values are increasing as the range to the target increases.
Why is this the case?
I believe it may be as a result of a logarithmic amplifier being applied to the intensity returns by the GLS-2000 scanner but I am not certain. Would this explain the boosted intensity values at higher ranges?
Any relevant information on relating to this issue would be greatly appreciated.
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Thank you both for your feedback. I am using the Topcon scanner, the raw data from which is encoded and must be brought through Scanmaster the proprietary software for this instrument. I can't inspect the data without first using this software. I am then using excel to interrogate the data.
The change to intensity has to be as a result of either the instrument itself or scanmaster.
The data I have collected over multiple scan sessions shows the intensity increases with range.
If this is not a logarithmic amplifier, them might you suggest what process is taking place to boost the intensity value?
Manufacturers do not tend to disclose the nature of the processes their instruments perform, at least not in the published spec.
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i am interested in first how can  fabricate the set up in which wire is moving at high speed ,and then by using laser scan micrometer how can measure the outside diameter of wire 
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dear Amit sir, 
                        i am very grateful with your valuable suggestion. can you send the paper regarding what you did with semi auto design.
                                                                                 with regards
                                                                                     sandeep kumar
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Hello!
I have recently found an image of a billet steel scanned with laser triangulation method. Image provided pretty entertaining test target for my image processing hobby but I obviously have no rights to use it in any professional or scientific way. Not to mention one image is not enough to do any meaningful research. That is why I am looking for a library of free or paid images with steel scans?
You can see the image under link below, Obr.1:
Thanks a lot!
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Every tip helps, thanks a lot :)
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I am looking for laser scanner for 2D measurement of profiles. The cost of the sensor no doubt depends on its specifications. So let's say for FOV < 20 cm, range < 40 cm, resolution < 1000 points. 
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Have you heard about the Lenovo Phab2Pro or the Google Tango Project?
Which will be available in September this Year.
It offers a PMD TOF Sensor
Following key figures should be interesting:
Res.: 224x169Px
Fov: 60°
depthRes.: 1mm
range: 0-8m
costs: ca. 500Euro incl. Smartphone.
If you need a more versatile Interface you can apply for a PMD/IFM HighRes Kamera:
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Lidar data need for the paralakhemundi area.
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You can check it out on USGS earthExplore sites
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What adjustments should i use to get proper pictures. Our confocal Laser Scanning microscope is the LSM 510 Meta from Zeiss, Germany.
Excitation/emission: 460/500 nm
My Problem is, that i am not sure if see background fluorescent or if these tiny dots are my particles.
These are my used parameters:
Laser: 488 (20%)
pinhole: 504 µm
Gain (Master) : 786
Digital Gain: -0,88
LP: 505
ocular:  20x
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Lukas,
Your settings looked fine for imaging 500 nm fluorescent particles. Since this is fluorescence microscopy the particles would only appear as bright or dim dots with a 20x objective. In other words these particles would only cover a few pixels each on your fluorescence microscope, unless you use total internal reflection fluorescence microscopy to achieve a much high signal to noise. The fine shape of the particles is lost in the fluorescence mode.
In fact for particles this large you could directly view them under bright field, using a 100x oil objective with a numerical aperture >1, preferably 1.4. The diffraction limit is 1.22 lambda/N.A., where lambda is ~500 nm for white light source). Switching between the bright field and fluorescence modes would give you a good idea what these particles look like.
Hope that helps.
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I am looking for information about using techniques other than typical surveying. I found publications about using airborne laser scanning, photogrammetry (also from UAV), but maybe there are some implemented solutions in program of monitoring of technical condition of levees. Links appreciated.
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I have 2 different laser scanning systems observing the same target, and each system observes and records a full waveform 'intensity' profile. Profiles recorded by each system may be similar or different, based on a number of variables.
Given neither profile is likely to conform to any predefined distribution (i.e. Gaussian, Poisson, etc.), and that each profile has the same number of observations, what is the best way to quantify if they are statistically similar?
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For 1d observations I would use the Kolmogorov-Smirnov test.
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Hey I want to buy 3d printer for medical purpose (orthopedic implant manufacuring), in detail i want to say that printer may be used for student experimental purpose as well as research purpose.
1-Please suggest me which printer should I go for and what should be the material used for printing implant.
Is their any combo machine through which I can print implant for demo purpose as well as research purpose.
2- and what about laser sacnner which should be used for same implant scanning and bone sacnning.
suggest model by which i can scan the longest and widest human bone.
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How is your applicaation ?, i will suggest the right detail ?
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Hello,
We are planing to use oil red 0 (OR0) in terms of showing which part of skin our microemulsions (ME) and ME based Gel formulations are being trapped by using laser scanning confocal microscope. Is there anybody can help us finding a protocol for this procedure?
Also, do you think it would have disadvantages using previously removed rat skin for this procedure as well?
Thank you very much in advance.
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The  AFIP Manuel can help you out. Remember that you can not  fix your  tissues. The way is to do a frozen  section  on your skins. Once you get a good section, immediately do the staining.  There are some good  commercial  kits that you can  purchase. 
Gogle the stain,then goggle the kits.
Let me know how your stains come out.
Cynthia Haynes-James 
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Dear Friends,
I am working of simulation for Selective Laser Melting(Additive Manufacturing). Simulation takes a powder layer of a metal typically of thickness 50um. Subsequently a laser beam (Gaussian ) scans a particular geometry. Powder melts to give molten metal and on cooling molten metal solidifies to metal that have different density(Implies solidified metal have different properties than initial powder taken). On starting I am simulating with spot laser scanning. I am having difficulty implicating how can we change properties of solidified metal while working with Heat transfer with Phase Change (Phase-1 Powder Phase-2 Molten) and solidified metal is having properties different then Phase 1 (There is basically volume shrinkage/density change between Phase-1-Powder and Solidified Metal)
Thank You in Advance :)
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Hi Harsh,
While I am not experienced in the field at all, I was curious by the problem at hand.
Since SLS is a powder sintering process, the resulting solid is in fact a porous material. It would make since that the density will increase (we are diminishing the pores around the powder solids). A google scholar search yielded a few interesting works. One of which is 
"Prediction of sintered density for bimodal powder mixtures"
I'm sure there are more models for this.
Hope this helps,
Elaid
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I have access to laser scans of tunnelsections before and after spraying the tunnel with shotcrete. Hence the first point cloud represents the geometry of the rock surfaces and the other point cloud represents the surfaces of the shotcrete.I would therefore like to use the pointcloud data to build a solid element to import in Abaqus for analysis.
I've tried to use programs such as VRMesh, Meshlab and Autocad and can easily create individual surfaces from the pointclouds, on for the rock surfaces and one for the shotcrete surface. I've so far been unable to join the surfaces to create a solid element. Booth surfaces are higly irregular so when i try to extrude one of the surfaces to create a solid element the geometry will clash into each other.
Any suggestion how to solve this problem?
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I think you are going the right way creating two surfaces.
You can try simplifying and checking for errors in each surface: holes, overlaps, etc and make sure each surface is only one entity or group or layer (depending on the software you use).
To create the volume I can think of two options:
1) Select the two surfaces and make a solid.
2) Create two solids and then take de difference of both to create a shell-like solid.
One way to check each surface will be using option two: if a solid can be created and meshed probably the surface is well defined.
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I am using sick laser scanner to make a map of an environment. The scans are recorded with time information. But the co-ordinates and reference point is ambiguous and not fixed.
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Hough Transform is usually used for parametric shape detection, e.g. line, circle. In this case if your robot wants to follow such path you can apply hough transform for path detection. Particle filter is used for tracking, which is related to SLAM (Simultaneous localization and mapping), the most important problem in robotics.
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I have an idea which may achieve ultra-high speed 2D (even 3D) laser scanning with scan frequency upto 10GHz. It means that within time of 100ps the laser focal spot can be moved round a circle or just from one place to another and returned according to your design. But I don't know what it can be used for.
As far as I know, the scan frequency of existing laser scanning techniques can be only up to several MHz. If my idea can be achieved, it will be a great improvement. So who can tell me potential applications of such a technique? OCT, Lidar or Confocal laser scanning microscopy?
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We have a second harmonic microscope setup in our lab. A femtosecond laser (400 mW) is used to scan the biological sample. The maximum scanning speed is 2 kHz. Though the scanner is fast enough the imaging speed is limited by the lock-in-amplifier. I would say if the scanner is faster than the current one, it is possible to use higher power laser for scanning/imaging the biological sample/other sample although the  lock-in-amplifier needs to work faster simultaneously.      
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Respected Sir,
I am developing Obstacle Avoidance Algorithms for MAVs as a part of my Masters Thesis. Can you please help me how to model the Laser Range Finder/Scanner Model in MATLAB for this purpose. How does one simulate Obstacles and How does one detect them using this Laser range finder Model? I will be highly thankful to you for your help. Thanks. Regards
Murali Mohan Gade
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Sorry! Here is the link to the paper I mentioned:
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I am looking for data description, links to data browsers including data collected by national institutions in other countries over the worlds.
What are their parameters?
How often they are collected usually?
Is there any official data browser?
For example, in Poland, ​​LIDAR of whole country with an average density of 4p/m2 and 12 p/m2 (for big cities) has been almost collected (90%). Link to the availability of data (DSM, DTM, LAS datasets) http://skorowidze.codgik.gov.pl/nmt/
Aerial photos are obtained every 2-3 years for whole country with a resolution of 10 cm (for big cities) and 25 cm or 50 cm for agricultural regions (depending on the size of real-estates) Link:
I'll be grateful for the assistance and support information about situation in your countries.
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In Italy at national level in 2008 a series of LIDAR measurements were done over almost 50% of the country focusing on populated areas, industrial areas and infrastructures. In 2011 the whole coastline was acquired.
Unfortunately the technical parameters are not easily to obtain. There is the National GeoPortal which includes the footprints of the LIDAR scenes acquired and all the derived products can be accessed both as CSW, WMS and ArcGIS service, but not the LIDAR scenes.
Furthermore the website, apart from the first pages, and the metadata are all in Italian, don't know how useful can be for you. However this is the link:
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We are planning to carry out some continuous landslide monitoring using a terrestrial laser scanner. We want to install the scanner in the field and leave it there for some months to carry out daily measurements.
Has anyone tried this before and can share some experiences? One thing that would be particularly interesting for me is how to protect the scanner (e.g. from vandalism).
Our initial plan was to use a small shed from the hardware store where we install a small hatch that can open and close by a simple garage door opener controlled by a timer clock. What do you think about this simple and cheap solution? Do you have any better ideas?
I am looking forward to your comments.
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Hi Benni, have you seen the new Leica Multi-station 'EDM' scanner, MS50. It would be set-up similar to a monitoring EDM and feed observations to deformation monitoring software for automatic surface difference analysis. I am using Duel and Single Frequency GNSS monitoring receivers feeding to Spider/Geomos deformation software to analyse movements in built and natural environments/structures. Power and comms are the biggest problem for 'off grid' installs, at present I am experimenting with solar panels, mini marine wind turbines to charge batteries. I use GPRS/3G data modems (low watt) to get the data off the instruments in the field. Monitoring EDMs are usually installed on a concrete pillar and surrounded by a small hut/shed with either an opening or perspex window (though I would expect the scanner will require a clean opening to insure good line of site to the target surface). Details of the MS50 system here:
Best,
Conor.
GAP QUB.