Carangiform type tail design for SMA spring actuator based soft robotic fish

Abstract

Among all aquatic animals found in water bodies, fish is one of the most preferred designs newlinefor making underwater robots due to its fast forward motion and manoeuvrability in any newlinedirection, its versatile body design useful at different depth densities and different environmental newlineconditions in the water body. A lot of robotic fishes have been introduced in the past few decades newlinein which various techniques, sensors, actuators and mechanismswere used. These sensors, newlineactuators, and mechanismsare developed based on the challenges aroused during the operation of newlinethese devises.Moreover, exploring the water bodies such as ponds, rivers, oceans, and seas has newlinebecome an area of interest and challenging task for researchers. The challenges include the newlineproblems related to enormous pressure developing with depth, underwater wireless newlinecommunication, robotic body design, waterproofing technology,swimming mechanisms etc. newlinePlenty of technologies related to underwater robotics have already been investigated, explored newlineand, developed till date, however, research work on the application of Shape Memory Alloy newline(SMA) based actuator in robotic fishes are not reported too much. newlineIn the present work, the critical review of SMA actuators, various bioinspired actuatorbased newlinesoft robots, and previous work related to robotic fish developed in the past decade in newlinevarious laboratories has been discussed. Based on the research gaps, the research objectives are newlinedesigned. The CAD modelling of the proposed robotic fish is done on SolidWorks. After critical newlinereview of the published work by various researchers, it was noticed that approx. 70% of the newlinedeveloped robotic fishes use conventional actuators like- DC motors, servo motors, and newlinepneumatic and hydraulic type actuators for developing forward swimming. Less power to weight newlineratio, high sound and vibration, complex rotational to oscillatory motion conversion mechanism, newlinecomplicated control and balancing system, more installation as well as operating space newlinerequirement etc. are some of the issues which need to b