According to the different forms of adsorption, wall-climbing robots can generally be divided into two types: negative pressure adsorption wall-climbing robots and magnetic adsorption wall-climbing robots. The wall-climbing robot we designed uses a more reliable permanent magnet adsorption scheme, which is based on the three-dimensional digital innovative design of the chassis. By expanding the working arm on the chassis, the robot has multi-functional and multi-scene production requirements. The wall-climbing robot with permanent magnet adsorption scheme has many advantages. First of all, the permanent magnet adsorption system has high stability and reliability, which can effectively maintain the stable adsorption state of the robot during the working process and reduce the risk of accidental fall due to adsorption failure. Secondly, the permanent magnet adsorption system has strong adsorption force and good adaptability, and can achieve firm adsorption under different wall materials and inclination angles to ensure that the robot can perform work tasks stably. In addition, the permanent magnet adsorption scheme also has the advantages of low energy consumption and low noise, which makes the robot more efficient and environmentally friendly in the working process. In the three-dimensional digital innovative design of the chassis, we can realize the precise positioning and motion control of the robot by introducing advanced sensor technology and intelligent control system. Through the three-dimensional modeling and simulation analysis of the chassis, the structural design of the robot can be optimized, and its motion flexibility and work efficiency can be improved. At the same time, by increasing the number of working arms and the scalability of functional modules, the robot can meet the diversified production needs in different fields and different scenarios. Our design has the following innovations 1. Optimize the magnet arrangement scheme that can balance the adsorption force and steering flexibility; 2. Analyze the magnetic adsorption force of the permanent magnet adsorption unit on the metal wall under different rubber sleeve thicknesses, and find out the most universal magnet selection for most materials; 3. Simple operation and reliable system: The robot adopts a multi-functional modular implementation scheme, which integrates functional design ideas and modular design ideas into the modeling, and can flexibly expand the functions of the robot by combining different working arms. In short, we have designed a magnetic robot chassis with adjustable contact length that has obtained a national patent. We have designed a three-dimensional digital innovative design of the wall-climbing robot chassis based on the permanent magnet adsorption scheme, which has high reliability and versatility. In the future, with the continuous development of technology, wall-climbing robots will further enhance their autonomy and intelligence level, bringing greater convenience and benefits to various industries.