劈接式油茶苗木嫁接机的研究
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摘要
机械嫁接是一种集机械、自动控制于一体的新技术,有效地解决了苗木的手工嫁接效率低、劳动强度大、嫁接苗成活率低等问题。嫁接自动化技术在农业生产上的广泛应用,为林业专用嫁接设备的研究提供重要的方法。嫁接机通常由供苗机构、取苗机构、切削机构、嫁接接合机构和夹持物投放机构等部分组成。
本文研究设计了基于劈接法的两种工作方式的油茶苗嫁接机器人,并通过建立机械系统的评价体系和评价指标,对油茶嫁接机机械系统优化选择,对今后嫁接机地深入研究具有借鉴和参考意义。采用Pro/Engineer三维设计软件以Top to Down的设计理念对基本机构进行设计分析,并进行运动仿真和干涉检查修正。
砧木和穗木的切削采用了“一刀两用”的方法,提高了由于砧木个体差异而影响的嫁接接合精度,简化了机械结构。采用使用经济、易操作、保水效果良好的C型硅胶套管取代人工劈接作业中使用的铝箔条固定砧、穗木,提高嫁接效率和嫁接成功率。套管的输送采用了摩擦轮机构,提高了套管输送的可靠性。砧木、穗木搬运机械手是采用圆柱型坐标系原理设计的多自由度串联机器人。
本研究采用Denavit-Hartenberg方法建立了相关数学模型,应用机器人运动控制理论、串联机器人操作手运动学等理论工具对砧、穗木搬运机械手进行了运动学分析,从而为机械手的运动控制提供分析的方法和手段。实验证明,该设计满足了油茶嫁接的要求。
研究中针对传统PC机或单片机系统在控制过程中对工作环境要求高,可靠性低等问题,提出将PLC作为控制器用于油茶嫁接机控制系统。
Mechanical grafting is a new technology in the integration of comprehensive mechanical technology and control theory. It effectively enhances manual grafting rate and survial ratio of seedling grafted, and reduces the worker labor intensity. Grafting automation technology is widely used in agricultural production. It is of important reference significance for the forestry grafting equipment. Usually, the grafting machine consists of seedling transportation agency, the carrying manipulator, the cutting mechanism, grafting jointing institutions and the gripping institution.
According to the grafting technological requirements of camellia oleifera seedlings , outward-feature proterties measurements and the design principles of electrical products, the design of grafting machine is completed. Based on the grafting operation mode“Cleft Grafting”of camellia oleifera seedlings, the camellia grafting machine mechanical system is selected optimally by the establishment of mechanical system evaluation system and evaluation indexes. The three-dimensional design software pro/Engineer is used to design the basic structure by the top to down design concept and to analyse the motion simulation and interference correction.
The root stock and scion cutting adoptes "a sword amphibious" method, which improves the grafting precision and simplifies the mechanical structure. The grafting machine uses soft rubber as the grafting matetials. The soft rubber tubes which are easy to obtain and of much lower price, with good elasticity and expansibility, are used to enclose and fix the grafting junction of rootstocks and scions. Besides, they are also good for preserving water of grafting wounds. It was found that using soft robber tube can reduce the production cost as well as improve the survival rate of grafted seedlings. Moreover, as the seedlings grow, soft rubber tubes can automatically peel off from the seedlings due to embrittlement, which saves the recycling process.The friction wheel transmission used in the conveying mechanism of‘C’type tube improves the reliability of the transmission of tubes.Seedling carrying manipulator is the key components. It is of vital significance that we take theoretical research on seedling carrying manipulator belonging to serial mechanism.
In the study Denavit-Hartenberg method were used to establish the mathematical model. The kinematics of the carrying manipulator are studied by means of the movement control theory, the robot serial robot kinematics. We established all sports rods joint movement and the manipulator actuators’posture in space. It provides the analysis method to control the motion of manipulator. The experimental results prove that the design meets the requirements.
In traditional PC or single-chip microcomputer control system used in automatic grafting machine control process is too hard for operation personnel. It is proved that PLC is appropriate for the automatic grafting machine control system.
本文研究设计了基于劈接法的两种工作方式的油茶苗嫁接机器人,并通过建立机械系统的评价体系和评价指标,对油茶嫁接机机械系统优化选择,对今后嫁接机地深入研究具有借鉴和参考意义。采用Pro/Engineer三维设计软件以Top to Down的设计理念对基本机构进行设计分析,并进行运动仿真和干涉检查修正。
砧木和穗木的切削采用了“一刀两用”的方法,提高了由于砧木个体差异而影响的嫁接接合精度,简化了机械结构。采用使用经济、易操作、保水效果良好的C型硅胶套管取代人工劈接作业中使用的铝箔条固定砧、穗木,提高嫁接效率和嫁接成功率。套管的输送采用了摩擦轮机构,提高了套管输送的可靠性。砧木、穗木搬运机械手是采用圆柱型坐标系原理设计的多自由度串联机器人。
本研究采用Denavit-Hartenberg方法建立了相关数学模型,应用机器人运动控制理论、串联机器人操作手运动学等理论工具对砧、穗木搬运机械手进行了运动学分析,从而为机械手的运动控制提供分析的方法和手段。实验证明,该设计满足了油茶嫁接的要求。
研究中针对传统PC机或单片机系统在控制过程中对工作环境要求高,可靠性低等问题,提出将PLC作为控制器用于油茶嫁接机控制系统。
Mechanical grafting is a new technology in the integration of comprehensive mechanical technology and control theory. It effectively enhances manual grafting rate and survial ratio of seedling grafted, and reduces the worker labor intensity. Grafting automation technology is widely used in agricultural production. It is of important reference significance for the forestry grafting equipment. Usually, the grafting machine consists of seedling transportation agency, the carrying manipulator, the cutting mechanism, grafting jointing institutions and the gripping institution.
According to the grafting technological requirements of camellia oleifera seedlings , outward-feature proterties measurements and the design principles of electrical products, the design of grafting machine is completed. Based on the grafting operation mode“Cleft Grafting”of camellia oleifera seedlings, the camellia grafting machine mechanical system is selected optimally by the establishment of mechanical system evaluation system and evaluation indexes. The three-dimensional design software pro/Engineer is used to design the basic structure by the top to down design concept and to analyse the motion simulation and interference correction.
The root stock and scion cutting adoptes "a sword amphibious" method, which improves the grafting precision and simplifies the mechanical structure. The grafting machine uses soft rubber as the grafting matetials. The soft rubber tubes which are easy to obtain and of much lower price, with good elasticity and expansibility, are used to enclose and fix the grafting junction of rootstocks and scions. Besides, they are also good for preserving water of grafting wounds. It was found that using soft robber tube can reduce the production cost as well as improve the survival rate of grafted seedlings. Moreover, as the seedlings grow, soft rubber tubes can automatically peel off from the seedlings due to embrittlement, which saves the recycling process.The friction wheel transmission used in the conveying mechanism of‘C’type tube improves the reliability of the transmission of tubes.Seedling carrying manipulator is the key components. It is of vital significance that we take theoretical research on seedling carrying manipulator belonging to serial mechanism.
In the study Denavit-Hartenberg method were used to establish the mathematical model. The kinematics of the carrying manipulator are studied by means of the movement control theory, the robot serial robot kinematics. We established all sports rods joint movement and the manipulator actuators’posture in space. It provides the analysis method to control the motion of manipulator. The experimental results prove that the design meets the requirements.
In traditional PC or single-chip microcomputer control system used in automatic grafting machine control process is too hard for operation personnel. It is proved that PLC is appropriate for the automatic grafting machine control system.
引文
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[5]贾治邦.积极稳妥推进油茶产业又好又快发展[J].湖南林业,2008(10):7-8.
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[7]彭阳生,奚如春主编.油茶栽培及茶籽油制取[M].北京:金盾出版社,2006,7-8.
[8]王锋锋,刘明刚,吴晓峰等.国内外苗木嫁接机器人研究现在与发展趋势[J].林业机械与木工设备,2011,39(1):16-18.
[9]辜松.蔬菜工厂化嫁接育苗生产装备与技术[M].北京:中国农业出版社,2006,73-76.
[10]铃木正肚.接ぎ木装置開発の现状と课题[J].研究ヅヤヘル,1996,19(8):16-24.
[11]鈴木正肚,小林研,猪之奥康治等.ウリ科野菜用接ぎ木装置の開発(第1報）一要素技術の検討[J].農業機械学会誌,1995:57(2):67-76.
[12]鈴木正肚,小林研,猪之奥康治等.ウリ科野菜用接ぎ木装置の開発(第2報）一要素技術の検討[J].農業機械学会誌,1995:57(3):103-110.
[13]小林研,鈴木正肚等.ウリ科野菜用接ぎ木装置の開発(第3報）－実験用接ぎ木装置による連続接ぎ木作業[J].農業機械学会誌,1996:58(2):83-93.
[14]小林研,小野田明彦,鈴木正肚等.ウリ科野菜用接ぎ木装置の開発(第4報）－実証試験と実用機の普及[J].農業機械学会誌,1996,58(3):59-68.
[15]山田久也.全自動接ぎ木ロボット[J].農業機械学会誌,1996,58(4):137-138.
[16]张品端.日本的蔬菜嫁接机器人[J].机器人技术与应用,1997(5):11-14.
[17]三代満．自動接ぎ木装置[J].農業機械学会誌,1997,59(2):l13-114.
[18]西浦芳史,穗波信雄,平知明等.接ぎ木苗生産の機械化に関する研究(第1報）－プラグイン法の提案[J].農業機械学会誌,1998,60(6):35-43.
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