repeated trial meaning in English

反复试验
重复试验

Sequence of repeated trials
重复实验序列
After establishing dynamics model of helicopter , we can design the control system for the helicopter , using the most advanced method . we can make our system gain the most excellent performance by repeating trial
本论文对直升机增稳控制系统进行研究、利用现有的直升机动力学模型以及针对该直升机模型建立的增稳控制系统建立一套直升机机动飞行控制仿真软件。