PiCUS Tree Motion Sensor Online

The PiCUS TMSO is an innovative system for the remote monitoring of tree groups. The sensors are based on the established TMS3 while the results are provided to the user directly using the new cloud-based data upload.

Measuring Procedure

Similar to the Tree Motion Sensors of the 3. generation the TMSO record tree tilt movements under natural wind influence. The combination of tree tilt data with wind velocity recordings represents the trees behaviour under wind load.

In order to save energy the TMSO focuses on periods of recognised movement. These are identified by comparing the raw data to the result of the assigned control sensor and stored in the cloud memory.

In the cloud the data may be accessed from any workstation – No need to spend time to fetch the sensors and get the data manually. The measuring results are available nearly in real time!

The PiCUS TMSO system is able to remain in position several months, under favourable conditions even up o whole year. Commands and status reports are exchanged via the cloud. Measuring cycles and data processing are conveniently managed from your desk at any time

System Layout

The PiCUS TMSO is designed as a network. The central node is the radio unit. It connects to up to 20 sensors which are mounted on trees in a radius of 50 meters and collects their data. The central radio unit uploads the collected data to the cloud where it is accessible for the user.

Control commands are entered on the computer, saved in the cloud, downloaded by the central unit and distributed to the sensors.                           

Energy Concept

Since the PiCUS TMSO system is optimized for long term measurements the second most important topic after measuring is energy management.

All components of the system of the system are designed to be as sparing with energy as possible and have large batteries. To increase the runtime further all devices are also equipped with solar cells. While the battery alone would last several months thanks to the enormous energy efficiency the solar energy recharges the batteries and increases the range significantly.

In theory the system allows runtimes under temperate conditions between half a year and one year!

The following example shows exemplarily the battery voltage of three TMSO components during a winter in temperate climate.                              

The presented period covers five months from the beginning of December to the end of April. The vertical lines each mark the beginning of a recorded wind event. During the recording the system consumes much more energy than in stand-by mode.

It can be seen that all devices discharge continuously but very slowly. It is also visible that beginning in March the number of sunny days increases and the batteries are being charged.

In case of the central unit the charging is especially fast because it has by far the largest solar panel. The sensors need more time to charge but also here the trend is obvious. Even sensor 28 which was started without being fully charged shows a clearly positive trend and has not been even close to the turn-off limit during the winter.

This PiCUS TMSO system is ready to measure some more months.

Example

This example shows a group of trees that belong to a stand that was monitored using PiCUS TMSO. The group consists of three firs (Abies grandis) and three oaks (Quercus robur). All recordings have been controlled by one assigned control sensor.

In this graphic the wind velocity (km/h) and tree inclinations (°) are plotted against the time.                         

At windspeeds of up to 78 km/h different inclinations were measured on the trees. The control sensor which is mounted higher regularly yields he highest values. It is easy to tell tat the oaks tilt less than the firs. Among the firs there is one specimen sticking out.

This impression is supported by the wind tipping curves. Here the inclination values of all senors are plotted against the wind velocity. Each curve represents the behaviour of an individual tree.                        

The conspicuous tree is number 18. The single tree data view highlights tree 18’s tilting behaviour.                        

The PiCUS TMSO easily allows to keep suspicious trees like this in sight.

This tree was identified in the group with very little effort and thanks to the untiring sensors it may be monitored continuously. Also in the next storm – near real time.