STIFF-FLOP

STIFF-FLOP held their final review meeting at King’s College London on 11 December 2015, under the watchful eye of Project Officer, Dr Michel Brochard.

Four new project evaluators from academia and industry offered their expertise, helped to evaluate this project, and shared their ideas on future technologies and exploitation opportunities in the area of soft, stiffness-controllable surgical instruments:

Read more: Final STIFF-FLOP Review Meeting: A great success

Scuola Superiore Sant’Anna (SSSA) has been working on the optimization and integration of the multi-module STIFF-FLOP manipulator and on the development of the end effector tool. The work on the multi-module manipulator included the optimization of the module structure integrating fibre-reinforced chambers for the bending/elongation of each section and additional chambers for the stiffening modulation based on the principle of granular jamming.

The developed end effector tool is a pneumatically actuated gripper which involves the same soft actuator approach used for the actuation chambers of the modules.

Read more: New pneumatically actuated gripper and miniaturized STIFF-FLOP arm

XIII Conference on Medical Robots 2015 addressed issues related to the implementation of robots in many kinds of medical applications.

New projects in the field of surgical robots, diagnostic, welfare and rehabilitation, implemented in Poland and international projects were presented. Furthermore, experience in using commercial robots was shared, and experts of surgery discussed the use of robots in practice.

Read more: XIII Medical Robots 2015 International Conference – Zabrze

On 13 October 2015, KCL, EAES, PIAP, SSSA and UNITO representatives met at the Institute for Medical Sciences and Technology (IMSaT) in Dundee, UK, for a one-day session on human cadavers. The team of engineers installed the entire STIFF-FLOP system including a multi-segment octopus-like robot equipped with a camera and associated software. At IMSaT all cadavers are routinely prepared by the so-called Thiel method which preserves humans in a very life-like, realistic state with regards to appearance and mechanical soft tissue properties.

Read more: World’s first soft-robotic surgery on a human body

Controlling stiffness is critical in procedures using soft surgical robots. In the final year of the STIFF-FLOP project, the University of Surrey developed a methodology to characterise the tuneable dynamic stiffness matrix and demonstrated its use for rejecting lateral and normal disturbances. This method of disturbance rejection was employed in conjunction with granular jamming to maintain the tip position of a three-segment STIFF-FLOP robot.

It is noted that this algorithm can be extended to multi-module soft robots. The research conducted by UoS verified why the reduction of stiffness at the tip is preferred for safety whilst greater stiffness is essential to undertake efficient tissue manipulation with surgical tools.

Furthermore, information on the forces exerted at the distal end of the robot manipulator and appropriate feedback control improved the robustness of motion of the system and contributed to the improvement of robot-environment interaction safety through precise manipulation.

Read more: Controlling The Stiffness

The Shadow Robot Company has developed new prototype modules for RoNeX with a view to extending the RoNeX range beyond the existing Bridge and GIO modules already commercially available.

Read more: New RoNeX modules

A new model has been proposed by PIAP for defining the Forward Kinematics of the flexible modules of our STIFF-FLOP robot arm. The model enables the estimation of the positions of the flexible modules, using as inputs: the pressures in the chambers and the external forces exerted onto the STIFF-FLOP arm. This new Forward Kinematics have been adjusted to be exploited to compute the generic Inverse Kinematics framework that deduces the appropriate system configuration needed for reaching a targeted tip position and orientation in space.

Read more: New model for the Forward Kinematics of the STIFF-FLOP arm

King’s College London and the University College London (UCL) organised a joint workshop on Soft Architecture Machines for postgraduate students at the Bartlett School for Architecture. The event was introduced by a brief historical overview of Soft Architecture Machines. Researchers from King’s demonstrated how to sew inflatable manipulators and create moulds for silicone-based robots, providing the UCL students with expertise and know-how on the manufacture of soft robots gained in the framework of the STIFF-FLOP project. Students tweeted their work using #softerarch.