Design And Experimental Study Of A Flexible Colonoscopy Robot

Regular colonoscopy can effectively prevent the occurrence of colon cancer,and can be effectively detected after the occurrence of colon cancer to significantly reduce the incidence of colon cancer.However,the colonoscopy material used now is mostly made of metal and other materials with greater hardness,which is highly likely to cause discomfort to patients in the process of examination,and may even further cause intestinal bleeding and other injuries to patients.Previous studies have shown that the use of soft materials or novel structure design can achieve certain results,but most of the complex structure,insufficient drive,poor safety,observation instability,insufficient control and other comprehensive problems need to be further improved and studied.Based on the actual requirements of colonoscopy,this paper proposes a design scheme of a soft pneumatic colonoscopy robot based on bionics,and finally prepares the prototype and completes the experimental verification.The specific contents of the study are as follows:Based on the structure and movement mode of elephant trunk in nature,with three independent air chambers as driving units and fiber lines as outer layer control,a kind of two-end colonoscopy soft robot with different cross sections was designed.Driven by controlling the amount of air pressure in a separate air chamber,the soft robot’s actuators can bend in all directions,allowing limited bending in a gut-like environment.Radial expansion is controlled by winding fiber lines around the outside of the actuator.Based on the piecewise constant curvature model,a one-stage kinematic model of the actuator is established and a two-stage kinematic model is derived.The stiffness model of the actuator is established under the condition that the radial deformation of the actuator is controlled by fiber line.ABAQUS simulation software was used to simulate and analyze various factors affecting the characteristics of the soft actuator,such as bending state,fiber line constraint state,and air cavity deformation.At the same time,the simulation condition is compared with the experimental condition.Finally,a comprehensive colonoscopy soft robot system is established,which uses solenoid valve and air pump to build pneumatic circuit and endoscope as monitoring system.Arduino is used as the core control software and Matlab GUI is used as the visual control platform to effectively collect and control the data of the electromagnetic valve,sensor and other components,and finally realize the bending and observation control of the colonoscopy soft robot in the intestine-like environment.