The Midge is a sensor device developed by the Socially Perceptive Computing Lab (SPCL) at Delft University of Technology (TU Delft). This device is used to monitor human behaviour in social settings using several sensors. In this paper, the accuracy of the Inertial Measurement Unit (IMU) chip used in the Midge sensor package was evaluated. The IMU is responsible for sensing motion in multiple directions using an accelerometer, gyroscope and magnetometer. This experiment was performed by comparing several Midge devices with each other as well as comparing them with a modern smartphone. First will be explained how the control software was updated to run on modern hardware (computers) and the work that was done to reliably convert the generated binary data to readable data (parsing). Then the process of creating the test setup, performing the tests and analyzing the data will be explained.