Factory raising seedlings is a raising seedlings method of integrating mechanical and automation
technology. There are many advantages to apply factory raising seedlings, such as scientific treatment seeds,
seeding and covering soil evenly, automatic sprinkling, appropriate temperature, growing uniformly and
producing high quality seedlings. And factory raising seedlings can also effectively reduce influence of
adverse weather conditions on seedlings, such as low temperature and rainy [4]. Therefore, it is widely
applied to produce seedlings of rice, vegetable and flowers [5]. Since factory raising seedlings is characterized
by saving water, saving work and low cost [6], it is an important way for rice planting mechanization [7],
especially developing three-dimensional carpet raising seedlings.