A robust error-space controller for an amplitude modulated resonating fiber scanner is developed and implemented. Using a nonlinear dynamics model, the system’s open loop temporal response for a spiral scan pattern is simulated and compared to experiments to understand scan distortions, such as, toroid, swirl, and beating. A feedback linearized linear quadratic regulator based on error dynamics drives the tracking error to zero. Controller simulations determine robustness limits, and effects of fiber nonlinearities and actuator time delay. Using real-time hardware, the controller asymptotically tracks and is capable of removing the scan distortions. Image acquisition with the controlled scanner produces nearly pixel accurate images.

1.
Seibel
,
E. J.
, and
Smithwick
,
Q. Y. J.
, 2002, “
Unique Features of Optical Scanning, Single Fiber Endoscopy
,”
Lasers Surg. Med.
0196-8092,
30
(
3
), pp.
177
183
.
2.
Smithwick
,
Q. Y. J.
, and
Seibel
,
E. J.
, 2002, “
Depth Enhancement Using a Scanning Fiber Optical Endoscope
,”
Proc. SPIE
0277-786X,
4613
, pp.
222
233
.
3.
Seibel
,
E. J.
,
Smithwick
,
Q. Y. J.
,
Brown
,
C. M.
, and
Reinhall
,
P. G.
, 2001, “
Single Fiber Flexible Endoscope: General Design for Small Size, High Resolution, and Wide Field of View
,” Biomonitoring and Endoscopy Technologies, in
Proceedings of the EOS/SPIE EUROPTO Series
, Vol.
4158
,
pp.
29
39
.
4.
Crespo da Silva
,
M. R. M.
, and
Glynn
,
C. C.
, 1978, “
Nonlinear Flexural-Flexural Torsional Dynamics of Inextensional Beams I&II
,”
J. Struct. Mech.
0360-1218,
6
(
4
), pp.
437
461
.
5.
Smithwick
,
Q. Y. J.
,
Reinhall
,
P.
,
Vagners
,
J.
, and
Seibel
,
E. J.
, 2004, “
Nonlinear State Space Model of a Resonating Fiber: Theory and Experiment
,”
ASME J. Dyn. Syst., Meas., Control
0022-0434,
126
(
1
), pp.
88
101
.
6.
Smithwick
,
Q. Y. J
,
Seibel
,
E. J.
,
Reinhall
,
P.
, and
Vagners
,
J.
, 2001, “
Control Aspects of the Scanning Single Fiber Flexible Endoscope
,”
Proceedings of SPIE
, International Symposium on BiOS 2001, Optical Fibers and Sensors for Medical Applications,
Vol.
4253
, pp.
176
188
.
7.
Slotine
,
J. J.
, and
Li
,
W. P.
, 1991,
Applied Nonlinear Control
,
Prentice-Hall
, New Jersey.
8.
Smithwick
,
Q. Y. J.
, 2002, “
Modeling and Control of the Single Fiber Scanning Endoscope
,” Ph.D. dissertation, University of Washington.
9.
Speigel
,
M. R.
, 1968,
Mathematical Handbook of Formulas and Tables
, Shaum’s Outline Series,
McGraw-Hill
, New York.
10.
Franklin
,
G. F.
, 1994,
Feedback Control of Dynamics Systems
,
3rd ed.
,
Addison-Wesley
.
You do not currently have access to this content.