A graphene based ink for printing passive electrical components (conductive traces, resistors, capacitors, inductors) and circuitry on mechanically flexible polymer substrates is described in this paper. The ink is synthesized by using carboxymethyl cellulose (CMC), a hydrophilic cellulose derivative, to suspend the naturally hydrophobic graphene (G) sheets in an aqueous solvent composed of 70% DI water and 30% 2-butoxyethanol. Once deposited on the functionalized substrate the conductivity of the printed electrical components can be optimized by decomposing the cellulose stabilizer using thermal reduction. Several printed passive electrical circuits are fabricated and tested including an interdigitated capacitive chemical sensor and a low-pass electrical filter. The measured characteristics of the printed circuits are compared with theoretical values for performance validation. Mechanical bending tests were also performed to demonstrate that the thermally modified G-CMC films can absorb large levels of strain without fracturing or degrading the electrical properties.

Angioplasty is a minimally invasive procedure wherein a catheter (a thermoplastic hollow wire) is inserted into the femoral artery and guided till it reaches a blockage in the blood vessel. There could be some potential complications arising from the conventional way of performing angioplasty, e.g., damage to the blood vessel due to excessive force of insertion and exposure of clinicians to harmful radiations and/or high levels of noise from an MRI machine. In this paper, we investigate the use of a robot manipulator (Mitsubishi PA 10-7C) to aid in the insertion of a catheter into a blood vessel. The robot controls the insertion force while the surgeon can remotely operate the robot from a safe and comfortable environment. The paper describes a hybrid impedance control scheme implemented on the Mitsubishi robot to perform simultaneous force/position control. The robot is used in experiments to insert a catheter into a test-bed by controlling the force of insertion and preventing the catheter from buckling or "bunching up". Experimental results for the insertion algorithms are shown