The current state of the art of balloon catheters relies solely on the application of a predetermined quantity of mechanical strain to the balloon during diagnostic and therapeutic procedures. In some cases, the surgeons can use radioactive-contrasting agents and x-ray screening to identify the correct position and size of the inflated balloon. Otherwise, there is little information on the inflated size of the balloon catheter in the occluded lumen. This gap in quantitative feedback of the ballooning behavior needs to be addressed to ensure safe operation. With the advancement in technology and breakthrough in flexible electronics in recent years, kirigami, an ancient cutting, bending and folding technique, is explored in the stretchable sensing field due to its ability to transform 2D planar patterns 3D geometry structures. On top of that, kirigami can increase the mechanical strain by over 300% depending on the different cuts and folds and sensitivity over 80%. This manuscript will address this limitation of conventional balloon catheters by introducing strain sensing using kirigami technology to achieve a better, safer, and more efficient treatment procedure. Experimental results show that the change in normalized resistance of the sensor is directly proportional to the change in the size of the balloon.

The feasibility of using chip-based RFID designs as wireless sensor tags open a wide range of application possibilities in the field of robotics. However, multi-step lithography manufacturing and/or MEMS techniques are often required for the industrial-grade fabrication of such sensors. In this paper, we present a simple, home-based, two-step fabrication process to produce chipless RF-based wireless sensors. We use an office-based inkjet printer to produce the antenna traces using silver conductive ink. Kirigami-inspired designs are used to produce four sensors responsive to various mechanical stimuli commonly used for DIY robotic projects (contact, compression, extension, and bend). We demonstrate sensing and wireless transmission of the detected mechanical stimuli through the proposed chipless sensor tags with reliable consistency. The tags can be replicated quickly with the inkjet-printing method. This paper also contains analyses on the effects of varying the dimensions and electrical parameters of the tags. The developed antennas in this work can be used as wireless mechano-responsive sensors for robotic applications.