Imperial College London

Dr Thrishantha Nanayakkara

Faculty of EngineeringDyson School of Design Engineering

Reader in Design Engineering and Robotics



+44 (0)20 7594 0965t.nanayakkara Website CV




RCS1 M229Dyson BuildingSouth Kensington Campus






BibTex format

author = {Akhond, S and Herzig, N and Wegiriya, H and Nanayakkara, DPT},
doi = {10.1109/ACCESS.2019.2923144},
journal = {IEEE Access},
pages = {1--13},
title = {A method to guide local physical adaptations in a robot based on phase portraits},
url = {},
volume = {7},
year = {2019}

RIS format (EndNote, RefMan)

AB - In this paper, we propose a method that shows how phase portraits rendered by a controller can inform the development of a physical adaptation at a single degree of freedom (DoF) for a given control task. This approach has the advantage of having physical adaptations sharing the responsibility of control to accomplish a task. We use an inverted pendulum which is reminiscent of the trunk of a biped walker to conduct numerical simulations and hardware experiments to show how our method can innovate a physical adaptation at the pivot joint to reduce the control effort. Our method discovered that a torsional spring at the pivot joint would lead to a lower input effort by the regulator type feedback controller. The method can tune the spring to minimize the total cost of control up to about 32.81%. This physical adaptation framework allows multiple degrees of freedom robotic system to suggest local physical adaptations to accomplish a given control objective.
AU - Akhond,S
AU - Herzig,N
AU - Wegiriya,H
AU - Nanayakkara,DPT
DO - 10.1109/ACCESS.2019.2923144
EP - 13
PY - 2019///
SN - 2169-3536
SP - 1
TI - A method to guide local physical adaptations in a robot based on phase portraits
T2 - IEEE Access
UR -
UR -
UR -
VL - 7
ER -