Imperial College London
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Professor Thrishantha Nanayakkara

Faculty of Engineering, Dyson School of Design Engineering

Professor in Robotics
 
 
 
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Contact

 

+44 (0)7902 396 681t.nanayakkara Website CV

 
 
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Location

 

RCS 1M07Dyson BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Sadati:2020:10.1109/LRA.2020.2972790,
author = {Sadati, H and Shiva, A and Herzig, N and Rucker, C and Hauser, H and Walker, I and Bergeles, C and Althoefer, K and Nanayakkara, DPT},
doi = {10.1109/LRA.2020.2972790},
journal = {IEEE Robotics and Automation Letters},
pages = {2824--2831},
title = {Stiffness imaging with a continuum appendage: Real-time shape and tip force estimation from base load readings},
url = {http://dx.doi.org/10.1109/LRA.2020.2972790},
volume = {5},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - In this letter, we propose benefiting from load readings at the base of a continuum appendage for real-time forward integration of Cosserat rod model with application in configuration and tip load estimation. The application of this method is successfully tested for stiffness imaging of a soft tissue, using a 3-DOF hydraulically actuated braided continuum appendage. Multiple probing runs with different actuation pressures are used for mapping the tissue surface shape and directional linear stiffness, as well as detecting non-homogeneous regions, e.g. a hard nodule embedded in a soft silicon tissue phantom. Readings from a 6-axis force sensor at the tip is used for comparison and verification. As a result, the tip force is estimated with 0.016–0.037 N (7–20%) mean error in the probing and 0.02–0.1 N (6–12%) in the indentation direction, 0.17 mm (14%) mean error is achieved in estimating the surface profile, and 3.4–15 [N/m] (10–16%) mean error is observed in evaluating tissue directional stiffness, depending on the appendage actuation. We observed that if the appendage bends against the slider motion (toward the probing direction), it provides better horizontal stiffness estimation and better estimation in the perpendicular direction is achieved when it bends toward the slider motion (against the probing direction). In comparison with a rigid probe, $\approx \!\!10$ times smaller stiffness and $\approx \!\!7$ times larger mean standard deviation values were observed, suggesting the importance of a probe stiffness in estimation the tissue stiffness.
AU  - Sadati,H
AU  - Shiva,A
AU  - Herzig,N
AU  - Rucker,C
AU  - Hauser,H
AU  - Walker,I
AU  - Bergeles,C
AU  - Althoefer,K
AU  - Nanayakkara,DPT
DO  - 10.1109/LRA.2020.2972790
EP  - 2831
PY  - 2020///
SN  - 2377-3766
SP  - 2824
TI  - Stiffness imaging with a continuum appendage: Real-time shape and tip force estimation from base load readings
T2  - IEEE Robotics and Automation Letters
UR  - http://dx.doi.org/10.1109/LRA.2020.2972790
UR  - http://hdl.handle.net/10044/1/77376
VL  - 5
ER  -
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