Internship | Signal processing photoplethysmography from a wearable optic patch in relation to biomedical impact

Using hybrid printed electronics technology, Holst Centre has developed a wearable optic sensor by integrating silicon photodiodes with multiple light sources and readout electronics into a lightweight and flexible patch. By recording optical signals from the skin using light sources with different wavelengths, our patch simultaneously measures signals from different skin depths. This provides advantages to overcome significant challenges in the field. ​​​​​​​ Our current R&D is focused on photoplethysmography (PPG) by recording optical signals from the illumination of the human tissue. Morphological features from the PPG signal can be translated into multiple patho-physiologies, from cardiovascular disease to diabetes. Different optical wavelengths have differing efficiencies of absorption dependent on biomolecules. As such there is a growing interest to further investigate common PPG features and there prevalence with increased wavelength possibilities.

Your challenge
Working in an interdisciplinary team of engineers and scientist (electrical engineering, material science, biomedical photonics), you will measure and analyse PPG signals using Holst Centre’s wearable optical sensor patch and existing software platforms. The challenges reside in:

• Obtaining reliable PPG signals and extracting morphological features from the sensors;
• Linking the sensors to existing physical conditions of individuals, in particular with an interest in cardiovascular diseases (CVDs).

Project goal

• Gain a basic understanding of biomedical optics and of propagation of light in human tissue;
• Provide a literature review on PPG signal analysis and biomedical biomarker extraction, with a focus on the dicrotic notch;
• Determine methodologies used within literature to assess alterations in signal;
• Develop protocols for evaluation of morphology with test optical devices;
• Acquire PPG signals with Holst Centre’s wearable optical patch;
• Conduct experiments and potential volunteer study;
• Communicate via presentations and report writing findings.

Your tasks
As a team member your tasks will be:

• Knowledge acquisition through literature survey, discussion with her team members, and internal seminars/colloquiums;
• Data acquisition through measurements;
• Analysis and presentation of experimental data;
• Documentation of results in a technical report or scientific publication;
• Presentation of results in internal seminars/colloquiums.

Your Profile

• A master degree in biomedical engineering, electrical engineering, physics, optics or related with both theoretical and experimental skills;
• Knowledge in signal processing, filtering, calibration, data analysis using MATLAB/Python or other platforms;
• Experience in signal processing and algorithms development;
• You have good communication skills in English;
• Independent but also a team player;
• Affinity for biomedical photonics;
• Analytical skills – ability to make analysis of complex situation and make a plan forward.

You want to work on the precursor of your career; a work placement gives you an opportunity to take a good look at your prospective future employer. TNO goes a step further. It’s not just looking that interests us; you and your knowledge are essential to our innovation. That’s why we attach a great deal of value to your personal and professional development. You will, of course, be properly supervised during your work placement and be given the scope for you to get the best out of yourself. Naturally, we provide suitable work placement compensation.

At TNO, we innovate for a healthier, safer and more sustainable life. And for a strong economy. Since 1932, we have been making knowledge and technology available for the common good. We find each other in wonder and ingenuity. We are driven to push boundaries. There is all the space and support for your talent and ambition. You work with people who will challenge you: who inspire you and want to learn from you. Our state-of-the-art facilities are there to realize your vision. What you do at TNO matters: impact makes the difference. Because with every innovation you contribute to tomorrow’s world. Read more about TNO as an employer.

At TNO we encourage an inclusive work environment, where you can be yourself. Whatever your story and whatever unique qualities you bring to the table. It is by combining our unique strengths and perspectives that we are able to develop innovations that make a real difference in society. Want to know more? Read what steps we are taking in the area of diversity and inclusion.

After the first CV selection, the application process will be conducted by the concerning department. TNO will provide a suitable internship agreement. If you have any questions about this vacancy, you can contact the contact person mentioned below.

Students must reside in the Netherlands before the start and also throughout the internship or graduation project at TNO.