Xiao Ai is an intelligent robot system based on artificial intelligence voice assistant developed by Computer College of China University of Science and Technology. It can talk to users through voice interaction and provide corresponding services and answers according to users' needs. Xiao Ai understands users' questions and gives answers through speech recognition, semantic analysis and natural language generation. Its estimation function means that in some practical problems, Xiao Ai students can perform some numerical calculation and data estimation according to the existing data and algorithms, and provide the answers that users need. For example, estimate the result of a mathematical calculation problem, or estimate the traffic congestion in a city. In a word, Xiao Ai's estimation function enables him to estimate data and answer questions in a certain field.