self-walking small car是什么意思

用法例句

The paper expounds how to rebuild bridge ship-unloader with self-traveling trolley using AC variable frequency control as well as the development history of unloader and its electric control technology.

文章介绍了在宝钢桥式自行小车式卸船机中应用交流变频控制系统的改造方案,简述了卸船机机型及其电控技术的发展历程,分析了自行式小车在交流变频改造中的重点和难点问题,然后对攻克方法进行了重点阐述,并给出了现场运行的结论。