Chapter title |
Implementation and Tuning of an Optical Tweezers Force-Clamp Feedback System
|
---|---|
Chapter number | 5 |
Book title |
Optical Tweezers
|
Published in |
Methods in molecular biology, January 2017
|
DOI | 10.1007/978-1-4939-6421-5_5 |
Pubmed ID | |
Book ISBNs |
978-1-4939-6419-2, 978-1-4939-6421-5
|
Authors |
Michael Bugiel, Anita Jannasch, Erik Schäffer, Bugiel, Michael, Jannasch, Anita, Schäffer, Erik |
Abstract |
Feedback systems can be used to control the value of a system variable. In optical tweezers, active feedback is often implemented to either keep the position or tension applied to a single biomolecule constant. Here, we describe the implementation of the latter: an optical force-clamp setup that can be used to study the motion of processive molecular motors under a constant load. We describe the basics of a software-implemented proportional-integral-derivative (PID) controller, how to tune it, and how to determine its optimal feedback rate. Limitations, possible feed-forward applications, and extensions into two- and three-dimensional optical force clamps are discussed. The feedback is ultimately limited by thermal fluctuations and the compliance of the involved molecules. To investigate a particular mechanical process, understanding the basics and limitations of the feedback system will be helpful for choosing the proper feedback hardware, for optimizing the system parameters, and for the design of the experiment. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
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Unknown | 8 | 100% |
Demographic breakdown
Readers by professional status | Count | As % |
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Professor | 3 | 38% |
Researcher | 1 | 13% |
Other | 1 | 13% |
Student > Postgraduate | 1 | 13% |
Unknown | 2 | 25% |
Readers by discipline | Count | As % |
---|---|---|
Biochemistry, Genetics and Molecular Biology | 2 | 25% |
Agricultural and Biological Sciences | 2 | 25% |
Physics and Astronomy | 1 | 13% |
Engineering | 1 | 13% |
Unknown | 2 | 25% |