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Insect cells may be preferred over mammalian cells for biofabrication because of several bioprocess benefits including tolerance to fluctuations in the external environment, low secretion of and sensitivity to toxic by-products and ease of genetic modification. Insect muscle cells, in particular, are functionally promising in vitro but have yet to find a purpose outside of basic research. Insect muscle cell development and physiology are well-documented and myogenic cell populations from a variety of species and tissue types have been propagated in vitro. Muscle cells can be easily isolated from insect embryos or metamorphosing stages, separated from contaminating cell types and triggered to differentiate via administration of insect-specific hormones. The abilities of insect cells to grow under ambient conditions, survive and function (i.e., contract) for extended periods of time without fresh nutrients and to exhibit powerful contractions present an attractive alternative to mammalian cell culture in the context of advanced manufacturing processes. Moreover, insect cells are less costly to produce at large-scale, lowering barriers to commercialization. Bioactuation devices, cultured meat and ingestible vaccines have been identified as promising areas of application for insect cell cultivation, with others likely to emerge. Some of the next steps to advance insect cell-based technologies include the design of control systems to regulate in vitro contractions, adaptation of tissue engineering techniques for invertebrate cells, scaling insect cell and tissue formation to meet the needs of these broader applications, and evaluation of food nutrition and safety.

The development of truly biomimetic robots requires that soft materials be incorporated into the mechanical design and also used as an integral part of the motor control system. One approach to this challenge is to identify how soft animals control their movements and then apply the found principles in robotic applications. Here I show an example of how a combination of animal kinematics, neural patterning and constitutive modelling of tissues can be used to explore motor control in the caterpillar, Manduca sexta. Although still in the early stages, these findings are being used to design and fabricate a new type of robot that does not have a rigid skeleton and is structured entirely from soft or compliant materials. It is hoped that this new robotic platform will promote the development of actuators, sensors and electronics that are compatible with soft materials.

Soft materials have many important roles in animal locomotion and object manipulation. In robotic applications soft materials can store and release energy, absorb impacts, increase compliance and increase the range of possible shape profiles using minimal actuators. The shape changing ability is also a potential tool to manipulate friction forces caused by contact with the environment. These advantages are accompanied by challenges of soft material actuation and the need to exploit frictional interactions to generate locomotion. Accordingly, the design of soft robots involves exploitation of continuum properties of soft materials for manipulating frictional interactions that result in robot locomotion. The research presents design and control of a soft body robot that uses its shape change capability for locomotion. The bioinspired (caterpillar) modular robot design is a soft monolithic body which interacts with the environment at discrete contact points (caterpillar prolegs). The deformable body is actuated by muscle-like shape memory alloy coils and the discrete contact points manipulate friction in a binary manner. This novel virtual grip mechanism combines two materials with different coefficients of frictions (sticky-slippery) to control the robot-environment friction interactions. The research also introduces a novel control concept that discretizes the robot-environment-friction interaction into binary states. This facilitates formulation of a control framework that is independent of the specific actuator or soft material properties and can be applied to multi-limbed soft robots. The transitions between individual robot states are assigned a reward that allow optimized state transition control sequences to be calculated. This conceptual framework is extremely versatile and we show how it can be applied to situations in which the robot loses limb function.

Robots built from soft materials can alter their shape and size in a particular profile. This shape-changing ability could be extremely helpful for rescue robots and those operating in unknown terrains and environments. In changing shape, soft materials also store and release elastic energy, a feature that can be exploited for effective robot movement. However, design and control of these moving soft robots are non-trivial. The research presents design methodology for a 3D-printed, motor-tendon actuated soft robot capable of locomotion. In addition to shape change, the robot uses friction manipulation mechanisms to effect locomotion. The motor-tendon actuators comprise of nylon tendons embedded inside the soft body structure along a given path with one end fixed on the body and the other attached to a motor. These actuators directly control the deformation of the soft body which influences the robot locomotion behavior. Static stress analysis is used as a tool for designing the shape of the paths of these tendons embedded inside the body. The research also presents a novel model-free learning-based control approach for soft robots which interact with the environment at discrete contact points. This approach involves discretization of factors dominating robot-environment interactions as states, learning of the results as robot transitions between these robot states and evaluation of desired periodic state control sequences optimizing a cost function corresponding to a locomotion task (rotation or translation). The clever discretization allows the framework to exist in robot's task space, hence, facilitating calculation of control sequences without modeling the actuator, body material or details of the friction mechanisms. The flexibility of the framework is experimentally explored by applying it to robots with different friction mechanisms and different shapes of tendon paths.