PiCUS TMS – Tree Motion Sensor

PiCUS TMS – Tree Motion SensorThe Wind-Reaction-Measurement with PiCUS TMS is used for in depth tree inspections to obtain information about a tree’s stability, defined by its root anchoring force in

  • Product Name:PiCUS TMS – Tree Motion Sensor
  • Model:PiCUS TMS
  • Maunufactor:Argus
  • Country:DE

PiCUS TMS – Tree Motion Sensor

The Wind-Reaction-Measurement with PiCUS TMS is used for in depth tree inspections to obtain information about a tree’s stability, defined by its root anchoring force in the ground.

  • PiCUS TMS 3 – consistently innovative

  • Bluetooth-communication – control via mobile phone

  • New inclination measurement – quick and simple installation

  • Small and stealthy – Even you will have trouble finding it!

Wind-Reaction-Measurement – the method

The Wind-Reaction-Measurement records the dynamic sway motion of a tree in naturally occurring wind, by measuring the root plate tilt.


The trees reaction is measured directly, including all environmental influences.

These include tree specific parameters (size, form of the crown, etc.), wind strength and wind exposition (buildings and other trees in the vicinity).

In contrast to this the tree pulling test (Wessolly & Erb, 1998), an established method for assessing root defects, uses an artificial wind replacement load. However, an estimate for the correlation between actually occurring natural wind and the artificial wind replacement load is rather difficult because of the previously mentioned environmental influences.

Typical applications for Wind-Reaction-Measurements

Confirmation of stability

If trees only show a small root plate tilt, even in strong wind gusts, one can assume a stable root system.

Identification of trees with root anchorage problems

After measuring tree groups comparing the results can identify trees with conspicuously large root plate tilt.

Combination with static tree pulling test (TreeQinetic) with regards to stability

If a tree with increased tilt angles has been identified, it is often meaningful to follow up with a static pulling test to measure the trees reaction to a known force.

Addition to sonic tomography (PiCUS Sonic Tomograph) and resistance tomography (TreeTronic3)

Trees with large defects in the lower stem area (with assumed root defects) should additionally have their stability tested in natural wind

Surveillance of trees near construction

Sustained changes in a tree’s tilt angle during groundworks (e.g. placing of sheet pile walls) can be detected with the PiCUS TMS.

Long term monitoring of trees

Trees suspected of having root anchorage problems can be inspected in regular intervals to check whether:

  • The root plate tilt in wind decreases (tree grows new and stronger roots)

  • The root plate tilt in wind increases (roots are dying off or get damaged otherwise)

  • The reaction remains constant

Parameter                                                PiCUS TMS 3                                     PiCUS TMS

General characteristics          

colour                                                      grey                                                   black

weight                                                       73 g                                                   270 g

dimensions                                        61 mm x 41 mm x 20 mm                    100 mm x 80 mm x 75 mm

protection                           Completely sealed against water and dust     Protected against rain and dust

warranty                                                     5 years                                                2 years


Accuracy tilt measurement                   0,03 °                                                   0,03 °

Measurement interval                             0,05 s (20 Hz)                                    0,05 s (20 Hz)

Type of tilt measurement                      3D measurement                               2D measurement

Sensor orientation                                  arbitrary                                                horizontal

Accuracy temperature measurement    1 °C                                                      1 °C

Temperature range                                   -20 – +50 °C                                      -20 – +50 °C


Battery capacity and runtime               250 mAh; > 14 days                               2900 mAh; > 20 days

Charging                                                    wireless                                                 Micro USB cable

Charge duration                                        approx. 2 h                                           approx. 6 h

recommended charging temperature     5 – 35 °C                                         5 – 35 °C


Memory type                                                                                                               MicroSD memory card

Memory size                                               256 MB                                                     Up to 32 GB

Memory runtime                                        20 days                                     > 130 days (1 GB memory card)


Standby- and measuring mode            Bluetooth Low Energy 4.0                            Micro USB cable

Data download                                       Bluetooth Classic 2.1                                     MicroSD card reader


TMS power on                                        Magnetic key                                                   Electrical switch

Outdoor-handling        BLE-capable mobile phone (Android, iOS)+TMS 3 App      Electrical switch

Data download and analysis                 PC with Bluetooth Classic                               MicroSD card reader

                                      + TMS 3 Control software (direct sensor interaction)             + TMS PC software

PiCUS TMS-case              

Power supply                              230 V AC, 50 Hz (adaptor)                                             230 V AC, 50 Hz (adaptor)

Number of TMS-chargers         10 (wireless charge bays)                                              10 (MicroUSB cable charger)

Maximum number of TMS          20                                                                                   20

weight, filled (screws, cables, 10 TMS)    5,5 kg                                                               11 kg

Maße                                              48 cm x 35 cm x 15 cm                                         60 cm x 45 cm x 17 cm