Smart Artificial Soft Tissue - Application to a Hybrid Simulator for Training of Laryngeal Pacemaker Implantation.

Surgical simulators are safe and evolving educational tools for developing surgical skills. In particular, virtual and hybrid simulators are preferred due to their detailedness, customization and evaluation capabilities. To accelerate the revolution of a novel class of hybrid simulators, a Smart Artificial Soft Tissue is presented here, that determines the relative position of conductive surgical instruments in artificial soft tissue by inverse resistance mappings without the need for a fixed reference point. This is particularly beneficial for highly deformable structures when specific target regions need to be reached or avoided. The carbon-black-silicone composite used can be shaped almost arbitrarily and its elasticity can be tuned by modifying the silicone base material. Thus, objective positional feedback for haptically correct artificial soft tissue can be ensured. This is demonstrated by the development of a laryngeal phantom to simulate the implantation of laryngeal pacemaker electrodes. Apart from the position-detecting larynx phantom, the simulator uses a tablet computer for the virtual representation of the vocal folds' movements, in accordance with the electrical stimulation by the inserted electrodes. The possibility of displaying additional information about target regions and anatomy is intended to optimize the learning progress and illustrates the extensibility of hybrid surgical simulators.

iSens: A Fiber-Based, Highly Permeable and Imperceptible Sensor Design.

Embedded sensors are key to optimizing processes and products; they collect data that allow time, energy, and materials to be saved, thereby reducing costs. After production, they remain in place and are used to monitor the long-term structural health of buildings or aircraft. Fueled by climate change, sustainable construction materials such as wood and fiber composites are gaining importance. Current sensors are not optimized for use with these materials and often act as defects that cause catastrophic failures. Here, flexible, highly permeable, and imperceptible sensors (iSens) are introduced that integrate seamlessly into a component. Their porous substrates are readily infused with adhesives and withstand harsh conditions. In situ resistive temperature measurements and capacitive sensing allows monitoring of adhesives curing as used in wooden structures and fiber composites. The devices also act as heating elements to reduce the hardening time of the glue. Results are analyzed using numerical simulations and theoretical analysis. The suggested iSens technology is widely applicable and represents a step towards realizing the Internet of Things for construction materials.

Soft electromagnetic actuators.

Rigid electromagnetic actuators serve our society in a myriad of ways for more than 200 years. However, their bulky nature restricts close collaboration with humans. Here, we introduce soft electromagnetic actuators (SEMAs) by replacing solid metal coils with liquid-metal channels embedded in elastomeric shells. We demonstrate human-friendly, simple, stretchable, fast, durable, and programmable centimeter-scale SEMAs that drive a soft shark, interact with everyday objects, or rapidly mix a dye with water. A multicoil flower SEMA with individually controlled petals blooms or closes within tens of milliseconds, and a cubic SEMA performs programmed, arbitrary motion sequences. We develop a numerical model supporting design and opening potential routes toward miniaturization, reduction of power consumption, and increase in mechanical efficiency. SEMAs are electrically controlled shape-morphing systems that are potentially empowering future applications from soft grippers to minimally invasive medicine.

Resilient yet entirely degradable gelatin-based biogels for soft robots and electronics.

Biodegradable and biocompatible elastic materials for soft robotics, tissue engineering or stretchable electronics with good mechanical properties, tunability, modifiability or healing properties drive technological advance, and yet they are not durable under ambient conditions and do not combine all the attributes in a single platform. We have developed a versatile gelatin-based biogel, which is highly resilient with outstanding elastic characteristics, yet degrades fully when disposed. It self-adheres, is rapidly healable and derived entirely from natural and food-safe constituents. We merge all the favourable attributes in one material that is easy to reproduce and scalable, and has a low-cost production under ambient conditions. This biogel is a step towards durable, life-like soft robotic and electronic systems that are sustainable and closely mimic their natural antetypes.

Instant tough bonding of hydrogels for soft machines and electronics.

Introducing methods for instant tough bonding between hydrogels and antagonistic materials-from soft to hard-allows us to demonstrate elastic yet tough biomimetic devices and machines with a high level of complexity. Tough hydrogels strongly attach, within seconds, to plastics, elastomers, leather, bone, and metals, reaching unprecedented interfacial toughness exceeding 2000 J/m2. Healing of severed ionic hydrogel conductors becomes feasible and restores function instantly. Soft, transparent multilayered hybrids of elastomers and ionic hydrogels endure biaxial strain with more than 2000% increase in area, facilitating soft transducers, generators, and adaptive lenses. We demonstrate soft electronic devices, from stretchable batteries, self-powered compliant circuits, and autonomous electronic skin for triggered drug delivery. Our approach is applicable in rapid prototyping and in delicate environments inaccessible for extended curing and cross-linking.