Optimising mechanical, control and actuator design variables together as a co-design problem enables identifying novel and better-performing robot architectures. Typically, solving such problems using conventional optimisation methods yields a single, point-based solution. Deviating from the computed optima may be necessary to ensure physical feasibility, typically associated with a performance loss. In this work, we present a two-step cascaded optimisation approach to identify non-intuitive designs and recover the loss in performance by constructing a solution space. The solution space provides robustness in the form of permissible ranges of design variable values and enables the selection of a physically feasible design. In our study, we observe (1) up to 20% of the lost performance is recovered and (2) an improvement of 30 % on the task metric in comparison to an existing robot and (3) designs with cost savings of up to 10% can be identified.

Generating a curriculum for guided learning involves subjecting the agent to easier goals first, and then gradually increasing their difficulty. This work takes a similar direction and proposes a dual curriculum scheme for solving robotic manipulation tasks with sparse rewards, called MaMiC. It includes a macro curriculum scheme which divides the task into multiple subtasks followed by a micro curriculum scheme which enables the agent to learn between such discovered subtasks. We show how combining macro and micro curriculum strategies help in overcoming major exploratory constraints considered in robot manipulation tasks without having to engineer any complex rewards and also illustrate the meaning and usage of the individual curricula. The performance of such a scheme is analysed on the Fetch environments.

This paper presents the design of a single use disposable compliant surgical tooltip for a tele-operated surgical robot. The proposed design aims at mitigating bio-fouling of surgical tools. By implementing a monolithic design for surgical tooltip, the cleaning and sterilization processes needed after every surgery for traditional surgical robotic tools is considerably simplified. The proposed design has 3 degrees of freedom (DOF) with a modified serpentine joint for enhanced buckling strength and off-axis stiffness. A magnetic force based coupling is proposed as a means of transferring power through a hermetic barrier to maneuver the tooltip. The tooltip is thus coupled through a hermetically sealed tool shaft preventing biological material from entering the tool shaft. By having a pluggable tooltip, modularity is also achieved by interchangeable tooltip instead of replacing the whole tool during surgery. A prototype of the proposed design is developed and its functional performance is validated. Owing to the magnetic nexus which forms the magnetic coupling, the tool is named MagNex.