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 1. TOC
 {:toc}
 
-# Multiview
-
 # Photogrammetry
 Photogrammetry is the collection and organization of reliable information about physical objects and the environment through the process of recording, measuring and interpreting photographic images and patterns of electromagnetic radiant imagery and other phenomena.
 
-Photogrammetry was first documented by the Prussian architect [Albrecht Meydenbauer](https://opus4.kobv.de/opus4-btu/files/749/db186714.pdf) in 1867. Since then it has been used for everything from simple measurement or color sampling to record complex 3d <a href="https://en.wikipedia.org/wiki/Motion_field">motion fields</a>.
+Photogrammetry was first documented by the Prussian architect [Albrecht Meydenbauer](https://opus4.kobv.de/opus4-btu/files/749/db186714.pdf) in 1867. Since then it has been used for everything from simple measurement or color sampling to recording complex 3D [Motion Fields](https://en.wikipedia.org/wiki/Motion_field)
 
 <img src="images/data_model_photogrammetry.png" alt="Data Model of Photogrammetry">
 
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 <p>~ nanometer </p>
 
 <img src="images/atomic_force_microscope_block_diagram.png" alt="AFM">
+<iframe src="https://www.youtube.com/embed/8gCf1sEn0UU" frameborder="0" allowfullscreen=""></iframe>
 
+<iframe width="500" height="400" src="https://youtube.com/embed/F2d4Hq1CBdg" frameborder="0" allowfullscreen=""></iframe>
+
+<p>Image modes</p>
+<p>Contact mode, Tapping mode, Non-contact mode</p>
+
+<img src="images/scanning_probe_microscopy.png" alt="modes">
+
+Non-contact Mode: Oscillates above the adsorbed fluid layer on the surface during scanning
+
+<ul> <li> <p>References</p> <p><a href="https://www.highspeedscanning.com/">High Speed Scanning with SPM</a><br> <a href="https://www.nanosurf.com/en/support/afm-operating-principle">How does AFM work</a><br> <a href="https://www.nanoworld.com/?gclid=CjwKCAjw-e2EBhAhEiwAJI5jgwRZEaR0sOLoeR1_gK5ZF48CKQmBWZe04e8AGIwI9kFXPUt0MjP1_hoC5JoQAvD_BwE">Nanoworld</a><br></p> </li> <li> <p>AFM Probe</p> </li> </ul>
+<p><a href="https://www.nanoandmore.com/AFM-Probe-USC-F0.3-k0.3">AFM Probe USC-F0.3-k0.3-10, image above, $980 per 10</a>, <a href="https://www.budgetsensors.com/?gclid=CjwKCAjwnPOEBhA0EiwA609RefDrTdyqhnt17UPTZEnNslIPfxV10pRReItfPxQdJLqJY78li9KlWBoCT_AQAvD_BwE">Budgetsensors</a> <a href="https://www.agilent.com/cs/library/slidepresentation/Public/AFM%20Probe%20ManufacturingNanoworld_tip_technologyPRussell07.pdf">Fabrication steps of AFM Probes</a></p>
+
+<p><a href="https://www.sciencedirect.com/science/article/pii/S0304399118301797">Tip wear and tip breakage in high-speed atomic force microscopes</a></p>
 
 
 # Digitizer
+
+<a href="https://www.marposs.com/eng/application/technologies-touch-probes#:~:text=The%20working%20principle%20is%20quite,called%20the%20probe%20pre%2Dtravel.">Touch Probes</a>
+
+https://youtube.com/embed/vJdcbhGa7Jk
+
+<p>resistance between the balls and rollers.</p>
+
+<img src="images/probe_light.png" alt="ProbeLight">
+
+<a href="https://www.blum-novotest.com/en/products/measuring-components/workpiece-probes/tc50-tc60.html">BLUM, The trigger signal is generated via shading of a miniature light barrier</a>
+
+<ul> <li>CNC Machine -&gt; Workspace alignment/present setting / workpiece measurement, digitizing or inspection</li> </ul>
+<iframe src="https://youtube.com/embed/IcVv1So1n_8" frameborder="0" allowfullscreen=""></iframe>
+
+Passive Robot arm
+
+Optical Optically tracked touch probes
+<a href="https://www.gom.com/nl/metrology-systems/gom-taster.html">GOM</a>
+
+<img src="images/gom_touch_probe.jpg" alt="GOM touch probe">
+
+<div class="youtube-embed-wrapper"> <iframe src="https://youtube.com/embed/wt4PLgbwxQI?t=92" frameborder="0" allowfullscreen=""></iframe> </div>
+
+# DIY
+
+DIY Projects
+
+<p><a href="http://blog.dzl.dk/2018/08/21/3d-digitizer/">Digitizer</a></p>
+<p><a href="https://www.instructables.com/CNC-Manual-Touch-Probe/">Touch Probe</a></p>
+<p><a href="http://www.homemetalshopclub.org/news/12/presentation_1202.pdf">Building a Digitizing Probe</a></p>
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