In order to solve the problems of inconvenience detection because of attachment and corrosion on the hull wall,the design and adsorption analysis of the tracked underwater observation robot were carried out.Based on the design index and overall structure,the kinematic model was established to solve the theoretical adsorption force required by the single magnet in the state of linear decline and longitudinal overturning of the robot.Maxwell was used to optimize the parameters of the magnet model,and the single magnet,N-S positive and negative magnetization two magnets and three magnets on the track assembly were simulated,and the N-S positive and negative magnetization arrangement was determined.Finally,a functional prototype was manufactured for experimental verification.The results show that the static stability of the robot depends on its longitudinal overturning state,the theoretical adsorption force of the single magnet walking on land should reach 230 N,and the underwater motion should reach 140 N.The parameters of the magnet model are determined to be the thickness of backing plate is 3.5 mm,the thickness of magnet is 13 mm,and the thickness of simulation and experiment ship plates is 5 mm.The optimized contact distance between single magnet and metal wall is within 5 mm,the adjacent two N-S magnetizing layouts in both positive and negative directions,and the distance between equivalent single magnet and metal wall is within 6.5 mm.The constructed prototype verifies the effectiveness of the robot design indicators,and the thickness of the attachment is limited by the mud scraper.The magnet is reliably adsorbed within the contact distance between the magnet and the metal wall.