Lars at NTNU (Norwegian University of Science and Technology) was working on his Master’s thesis on developing a new protocol for measuring sensorimotor synchronization (SMS). As this is an interesting topic, the Energy Micro team was pleased to offer an EFM32 Tiny Gecko STK for his study. Take a look at this short research summary by Lars and see how he combined high reliability with low power consumption for his SMS measurement method.
EFM32 Tiny Gecko STK connected to LTap prototype board with sound, tapping sensor, and Bluetooth dongle
This blog post is based on the findings in Lars Bårdgard Åstveit’s Master’s Thesis in Engineering Cybernetics at NTNU.
The aim of the study has been to design, develop and validate a reliable, portable, and user friendly protocol to measure sensorimotor synchronization (SMS). SMS is used to indicate learning disabilities and diseases like ADHD, dyslexia, etc. It is typically studied by index finger tapping to a sequence of isochronous stimuli generated by a metronome.
SMS testing is currently carried out in the laboratory where the MATTAP protocol represents a gold standard for such measurements. Different approaches have been taken to develop SMS testing on smartphones, but they have shown limitations with respect to the required accuracy or simple data extraction. A new protocol, LTap, has been developed in this study.
LTap uses a Tiny Gecko Starter Kit, controlled over Bluetooth radio by an Android smartphone. This microcontroller was chosen for its nice features such as fast processing time, low power consumption and descriptive application notes for easy programming. The EFM32 TG provides raw measurement data based on the RTC in the EFM32 TG. The data is transferred by Bluetooth radio to the Android smartphone where they are stored, displayed and possibly exported for further analysis. LTap facilitates a simple and efficient data analysis, where the recorded data are stored as comma separated values. This format is used in previous SMS research methods. Data from LTap can therefore also be analyzed by these protocols.
The reliability of the protocol has been validated in two different ways. First, an SMS sequence was recorded simultaneously by the embedded circuit and a high speed camera, before being correlated. The results from this correlation validated the accuracy of the embedded circuit to be within the stated requirements, matching also the accuracy of MATTAP. Thereafter, a pilot test-retest study was performed, which replicated the results of previously published laboratory experiments.
Testing the accuracy of the circuit
The approach of using dedicated hardware to measure SMS may be a solution used in the future. The Bluetooth interface allows simple interfacing to most smartphones. The drawback of using embedded hardware is the difficulties in distributing the protocol. LTap requires additional physical components, and a ready-to-use protocol can therefore not be downloaded from the web such as other smartphone based protocols. However, the simple design and use of cheap parts allow the circuit to be mass produced, and it can thus be sold relatively cheap.
Would you like to write your thesis with Energy Micro? Contact our software manager, Marius Grannæs firstname.lastname@example.org or check out our University Program to find more opportunities for students: http://www.energymicro.com/company/university-program