The activPAL™ micro is available in two models (and with legacy availability and support for the activPAL3):
- activPAL4 (released 2018)
- activPAL4+ (released 2022)
- activPAL3 (released 2014) legacy support
All the activPAL micro models are 23.5mm wide, 43mm long, only 5mm thick and weigh 9.5grams (0.93″ x 1.7″ x 0.2″ and weighing 0.34 ounces).
The main difference between the activPAL4 and the legacy activPAL3 is that the activPAL4 stores the acceleration sensor data as a high resolution number (10bits per sample with a range of +4 to -4g). It is however compatible with the activPAL3 which has a lower resolution and range (8bits per sample across a range of +2 to -2g). The activPAL4 is warranted for a minimum 14 day recording capacity, the activPAL3, only 7 days.
The activPAL4+ features magnetometer and barometer sensors in addition to the accelerometer sensor found in the standard activPAL. This allows us to calculate elevation (providing measures of stair ascent and descent) and direction of stepping (time and steps taken in a straight-line is a useful descriptor for the location in which the stepping activity is taking place).
The extra sensors in the activPAL4+ reduce the maximum recording duration down to around seven days with these functions enabled.
For the activPAL4+ the calculated outputs are limited in the current software release to duration of straight line stepping and height change per stepping bout. At an events level, the heading is calculated for each step and the height change in each upright event. The activPAL4+ outcomes are still in development are designed for researchers with specific project requirements at the moment. We believe activPAL4+ provides an objective measure of stair use but this has yet to be independently validated.
The activPAL3 is a legacy support version for the activPAL3 models and is maintained to provide continuity for existing projects. We recommend the activPAL4 is selected for new projects.
Previous activPAL™ models from the PALfamily and their software compatibility are summarised below.
activPAL family history
Current and previous activPAL models and their software suite compatibility are show below.
Older PALfamily members (gone but not forgotten)
The activPAL3, launched in 2010, was our first triaxial activPAL and went through a number of iterations before being superceded by the smaller activPAL micro in 2014. Careful assessment should be made of the battery condition of older activPALs before use. As many of these activPALs are now more than ten years old their rechargeable batteries can be considered end-of-life. Any units with swollen cases or other evidence of battery disfunction should not be used. Due to the age of the activPAL3 family we caution against their use and recommend taking advantage of our trade-in discount offer to purchase new activPALs.
A version of the activPAL3C that provided vibro-tactile feedback for self-monitoring of sedentary bout duration (eligible for trade-in discount against any current activPAL micro model).
An update to the activPAL3, the activPAL3C introduced the distinctive curved end profile to the enclosure. The polarised enclosure has provided a signature design feature for all subsequent generations of the activPAL. The activPAL3C is eligible for trade-in discount against any current activPAL micro model.
The activPAL3, launched in 2010, was our first triaxial version of the activPAL (eligible for trade-in discount against any current activPAL micro model).
The original activPAL was launched in 2001. The activPAL professional stored only an single axis of acceleration data and came in a replaceable primary battery version and, latterly, a rechargeable version. All activPAL professional models are eligible for trade-in discount against any current activPAL model.
We have developed products for specific project requirements, for example:
SitFIT & Activator
Developed for for self-monitoring of Physical Activity and Sedentary Behaviour. A component of the European Union funded FP7 project EuroFIT. EuroFIT was funded from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 602170.
Lower-limb prosthesis monitoring
The Long-term Activity Monitor (LAM) was designed to be fitted inside the pylon in the shank of a prosthetic limb recording limb-use on a minute by minute basis for a +12 month period.