Objective  To discuss the feasibility of the structure of hybrid power chassis for high-gap sprayer in the paddy field, solve the problems of deep depression of the paddy field sprayer and poor passing performance in field, and meet rice planting mode and agronomic requirements in the southern region.

Method  The theoretical analysis of the steering and driving performance of the power chassis was carried out. The key components of the track and wheel traveling device and the transmission system of the whole machine were designed. The finite element software was used to track the trapezoidal bracket under static load conditions. After analyzing, the load distribution and weak parts of the crawler running device under full load were obtained, and the running device was optimized according to the analysis results.

Result  The chassis clearance was determined to be 950 mm and the track width was 20 mm. Under static full load conditions, the maximum stress on the crawler trapezoidal bracket, which was 128.87 MPa, occured at the hub connection, and the maximum displacement, which was 1.05 mm, occured at the joint of the load bearing wheel, meeting the strength performance requirements. The field test results showed that the driving speed ranged from 1 to 3 km/h, the minimum turning radius of the paddy field was 3 380 mm, the front wheel depth was 115 mm, and the rear depth was 63 mm.

Conclusion  The wheel-wheel composite power chassis structure is feasible. The performance of the whole machine meets the requirements of paddy field operations. The results of this study have certain reference values for the development of new paddy field high-gap sprayers.