蔬菜嫁接机器人关键技术的研究

【作者】 吕谷来；

【导师】 李建平；

【作者基本信息】 浙江大学 ， 生物系统工程， 2010， 硕士

【摘要】 以葫芦和西瓜为砧木和接穗,采用斜插法嫁接,测定了砧木和接穗的几何参数和力学特性,探索了机械损伤检测方式,实现了砧木子叶旋转角度和抓取点高度的判断,设计了斜插式嫁接试验台并进行了试验。结果如下：1)在压缩量为20%的前提下,葫芦的压缩强度为81.6KPa,西瓜的压缩强度为105.5kPa。葫芦和西瓜沿长轴剪切时的剪切强度为7.1KPa和0.032KPa,沿短轴剪切时的剪切强度为7.4KPa和0.034KPa。15mm、20mm和25mm长度的西瓜苗的压杆临界力Pcr为0.297N、0.161N和0.099N。2)以不同形式的打孔,圆形针打孔后砧木葫芦在一定时间内的微弱发光总量普遍比扁形针打孔后葫芦的微弱发光总量多。以不同角度打孔,60°打孔比45°和30°打孔后的微弱发光量都要高。以上说明微弱发光可以作为一种检测植物机械损伤的方式。3)对砧木俯视图通过腐蚀、形态学处理后,能成功将图像区域分割开的成功率为98%；以长短轴差值作为判断准则来区分真叶和子叶,成功率为97.9%。判断结果表明子叶区域质心和原点的连线与X轴所成的角度可以表示为子叶的角度。4)对砧木侧视图进行坐标体系变换、特征点提取后进行曲线模拟并进行了判断优化,总体误差在允许范围之内,处理时间控制在200～500ms之间,符合自动嫁接的要求。算法具有一定的鲁棒性,可用于瓜科类蔬菜苗的识别定位,克服了苗生长弯曲和子叶重叠的问题。5)设计了斜插式蔬菜嫁接机器人,主要工作部件包括接穗夹持机构、接穗切削机构、砧木生长点去除机构、砧木夹持断根机构、砧木打孔机构和接穗与砧木对接导向机构。能实现砧木的夹持、展平、断根、去除生长点、打孔和接穗的夹持、切削、砧木和接穗的接合作业。6)针对以往的夹持机构存在的不足,设计了一种可针对不同类型的嫁接苗实现定位夹持并保持其直线状态的夹持机构和能实现柔性夹持的气吸式接穗夹持手。针对斜插法的工作流程,设计了一种辅助机构,能引导接穗顺利插入到砧木的插接孔内。更多还原

【Abstract】 On the basis of vegetable grafting industry, calabash and watermelon were grafted by apical bud oblique cutting. The geometric parameters and mechanical properties of grafted seedlings were tested. Image processing technology was used to achieve the accurate location of the connection point and the angles of cotyledons. An oblique cutting grafting robot was designed. The main results are as follows:1) The compressive strengths of calabash and watermelon are 81.6KPa and 105.5kPa when compression volume is 20%. The shear strengths of calabash and watermelon are 7.1KPa and 0.032KPa along the long axis while 7.4KPa and 0.034KPa along the minor axis. The critical buckling loads of a column for the watermelon (Pcr) are respectively 0.297N,0.161N and 0.099N.2)The ultra-weak bioluminescence(UWL)amount of calabash hurted by circular needle is more than the amount of calabash hunted by flat needle while the UWL amount of calabash hurted along the 60°direction is more than ones along the 45°or 30°direction. The result shows that UWL is a feasible method to detect the mechanical damage of vegetables.3) Erode process was used to remove the euphylla and get the angles between the horizontal and cotyledons, then determine the adjust angle and the success rate of the division for the cotyledons and euphylla is 97.9%. The judgment method is feasible.4) The coordinate system was transformed. The judgement result for the accurate location of the connection point was gotten by curve simulation. The global error is acceptable and the treatment time is controlled in 200-500ms, which is in accordance with automatic grafting. The algorithm has certain robustness and is used to recognition the crawl point.5) An oblique cutting grafting robot was designed. It includes clamping mechanisms, root cutting mechanisms, a growing point cutting mechanism, a perforating mechanism and a docking mechanism.6) A clamping mechanism was designed to keep the vegetable seedlings vertical, and an auxiliary mechanism was designed to guide the Scion inserting into the rootstock.更多还原