生鲜饵料离散式投饵机设计与试验

Design and experiment of discrete feeder for fresh feed

针对目前专为生鲜饵料设计的投饵机种类较少,且凶猛肉食性水产生物生鲜饵料喂养过程中密集投喂易引起夺食致伤致死的现象,该研究以虎斑乌贼为例,基于离心式投饵原理,提出生鲜饵料离散式投饵机设计思路,设计以西门子PLC为控制核心,MCGS触摸屏为人机交互界面的自动投饵机。该投饵机设计了适用于生鲜饵料的振动分筛盘实现生鲜饵料逐条抛投,拥有饵料抛投速度、方向、仰角的实时可控的子系统以及多段程投饵模式,实现离散式投饵。投饵机基础性能测试和投饵模式验证试验结果表明,多段程投饵模式可实现纵向抛投距离1.8~8.0 m,横向抛投距离0~3.9 m,抛投面积约26 m^2范围内的饵料离散抛投,覆盖81.2%的8 m×4 m室内养殖池;该投饵机转盘转速小于900 r/min时,平均饵料破碎率低于3.3%,转速高于900 r/min时饵料破碎率激增,最大有效抛投距离10.5 m。该研究可为今后生鲜饵料投饵机和离散式投喂提供参考。

Fish feeding is a key process in fishery industry.With the advancement of fishery modernization,traditional manual feeding has been replaced by mechanized feeders.But most of existing feeders are designed for pellet feed,which are not quite suit for carnivorous aquatic species such as weevers,groupers,squids etc.Those species mainly feed frozen little fishes and shrimps called fresh feed.Taking Sepia pharaonis for example,the intensive droppoints of fresh feed caused by traditional feeders will make squids to fight for food and result in injury and death.Such phenominon highly raises the cost and reduces the production efficiency.In this study,the design idea of feeder with discrete casting for fresh feed was put forward.Firstly,in order to ensure that the feeder had a good effect on discrete droppoints of fresh feed,the multi-stage casting mode was specially designed.In this mode,the casting speed,direction and elevation angle of feeder can be adjusted in real time,which maked the droppoints of fresh feed relatively uniform and not gather in small area.In addition,to ensure feeding automation,the feeder was equiped with Siemens PLC and MCGS touching screen as the control core and human machine interface for user to adjust and monitor above running parameters.The static analysis of the electric pusher was done to ensure the necessary maximum load.And the complex-vector method was used to calculate the relation curve between running time of electric pusher and elevation angle to realize the accurate control of casting elevation angle.The relationship between elevation angle and pusher running time was close to the straight line.Furthermore,MATLAB was used to simulate the droppoints of the multi-stage casting mode and determine running parameters in the mode and the test was held in squid breeding site to confirm the basic performance and effect of the casting mode.The multi-stage casting mode test results showed that the feeder could realize the discrete casting with longitudinal casting distance range from1.8 to 8.0 m,crosswise casting distance range from 0 to 3.9 m,the casting area 26 m2.And this mode can cover 81.2%of 8 m×4 m indoor breeding pool.Since the test was held in dry pool and fresh feed slide in the ground,the casting area was greater than that shown in the simulation of 17.95 m2.The performance test results showed that the average feed breakage rate was 3.3%when the rotating speed of the feeding machine was less than 900 r/min,while the rotating speed was higher than 900 r/min the breakage rate increased rapidly.Therefore,the maximum effective throwing distance was 10.5 m in speed of 900 r/min.The results showed the feeder and multi-stage casting mode were effective to realize the discrete casting with relatively uniform droppoint distribution,which reduced the behavior of fighting for food to death.The study can provide references for feeders design and discrete feeding.