Inform@Risk Documentation

This page provides an overview of the measurement system as well as the other pages for the measurement system. In the following section, the structure of the instructional documents is explained.

All information is shared on the project website and this wiki. Feel free to contact us with comments, questions and general messages about the system. You can reach us under: moritz.gamperl@tum.de or singer@alpgeorisk.de.

All sensors in the system are based on one basic measurement node design, to which additional sensors can be attached easily. This way, the system can be very versatile while keeping the cost low. The basic measurement node can simply be attached to walls to measure inclination or e.g. crack elongation with an external crackmeter (figure \ref{fig:meascon}). In this case, we call it 'Infrastructure Node'. When subsurface sensors are attached to it, we call it 'Subsurface Node' or Low-Cost Inclinometer', depending on the drilling depth and according number of sensors attached.

The Low-Cost Extensometer on the other hand can be used to measure elongation along an axis, be it vertically (e.g. in a borehole) or horizontally (e.g. across a slope). It consists of the measurement wire, the measurement tools in a shaft and a potentiometric sensor. The latter is then attached to the ADC (Analog-Digital Converter) of the measurement node.

All measurement nodes should be connected to at least two LoRa gateways, which should ideally be located in safe spots, with as good as possible line of sight to all sensors. There is also an instructional manual for the LoRa gateway, but it is more general in comparison to the other manuals. This is because the gateway will be very specific to the site and not as versatile as the individual sensors. Still, the manual contains the general overview of what is needed. If you have questions about this, don't hesitate to contact us.

The integration of the sensors into public space is very important, especially in urbanized regions, because it can improve the acceptance of the system by the local population. As part of the social component, it is further addressed in section \ref{c:soc}.

In order to make reproduction of the system as easy as possible, several files and documents are published on the project website and this wiki: project website. The can be divided into instruction manuals, datasheets and 3D printing files. All software is published on the project's GitHub page.

In the following sections, all documents are listed and explained whenever necessary.

We created several instruction manuals. It starts with an overview of the system and the basic measurement node, which is needed for all other measurements. Then the attachments (Subsurface Probe and Low-Cost Inclinometer) are addressed. The Low-Cost Extensometer is last since it is based on a slightly different approach. They are listed in the following (clicking on the headlines directly leads you to the respective wiki page):

1. Overview
   Overview and general concepts.
2. Measurement Nodes Assembly
   Assembly of basic measurement nodes: PCB and 3D prints.
3. Software Installation
   Necessary steps for installing the software of the measurement nodes are explained.
4. Subsurface Probes
   Assembly and installation of subsurface probes, which extend about 1-2 m into the subsurface.
5. Low-Cost Inclinometer
   Assembly and installation of Low-Cost Inclinometer, which extend about 3-6 m into the subsurface.
6. Low-Cost Extensometer
   Assembly and installation of the horizontal and vertical Low-Cost Extensometer.

For some parts of the system, datasheets were produced. Like the instructional documents, they can be downloaded from the project website. Third-Party datasheets for the sensors and some of the components that were used are referenced in the respective instructional documents.

3D printing files are supplied for the measurement node, the Subsurface Probes (they are identical to the ones needed for the Low-Cost Inclinometer) and the Low-Cost Extensometer. They are sorted in this way on the website. Here, a short overview is given. Detailed instructions can be found in the individual instruction pages.

The 3D printing files for the measurement node comprise:

1. The files for the lid, which houses the power supply. Therefore, there are different versions, depending on if it is solar- or battery powered.
2. The files for the inclination sensor mount, which is attached to the PCB directly and necessary to be able to tilt the inclination sensor, so it is horizontal independent of the measurement node orientation.

TO BE FINISHED

ADD FIGURE

Within the integration of the public space, it is important to highlight that the designs of the sensors, accompanied by the illustrative elements used in this project, allowed a better acceptance and identification of the instruments by the community.

Although interventions were carried out to improve public spaces made up of benches and small seats, which incorporated sensors inside them, the acceptance of these in general terms was positive. However, in individual terms, some people felt that the location of some of these benches would become spaces for drug use. In addition, it would also become a point of territorial control by illegal armed groups. It is therefore essential that when replicating this project, joint planning is carried out with the community in terms of infrastructure for the improvement of public space.

Another important aspect to consider is the location of some sensors in urban-rural areas. Land cover and accessibility to these spaces were a challenge when installing and maintaining the sensors. In addition, it is also a challenge to locate these sensors for new personnel joining the project as there are no precise coordinates taken by GPS. Another aspect to consider in the integration of the sensors in this area is that the occurrence of a forest fire could affect many instruments and in this area there are already records of forest fires. I consider it important to mention this, to take it into account when replicating the system and reduce the risk of affecting the instruments.