In recent years, as China government policies in agriculture are focused on improving agriculture machinery, deep-fertilization liquid fertilizer applicator with high efficiency, low price, easy operation and environment protection attracts more and more concerns. Deep fertilization for liquid fertilizer is a technology that liquid fertilizer is application accurately in 120-150 mm depth soil, which decreases fertilizer volatilization, increases crop’s nutrient absorbance in fertilizer, decreases environmental pollution brought by fertilizer, and increases crop yield and quality. Deep fertilization for liquid fertilizer is to make the liquid fertilizer into the soil. Northeast Agricultural University developed all elliptic planetary gears for pricking hole mechanism of 1YJ-140 type deep-fertilization liquid fertilizer applicator.Although the mechanism was obtained via using design method for obverse operation, there were a certain blindness in the process of seeking the optimal parameters and a long process of seeking parameters. The transmission part of pricking hole mechanism adopted all elliptic planetary gears so its transmission ratio was fixed. It was difficult to find a perfect path curve. So the non-circular planetary gear trains for pricking hole mechanism was proposed. Several date points on the motion trace of fertilizer-spraying needle tip were selected, and then the curve fitting technique of cubic non-uniform B-spline was applied to control and ascertain the whole trace curve. The inverse kinematics model of the pricking hole mechanism was established on this basis. Then, other parameters could be reversed easily. To meet agronomic requirements of verticality and hole mouth size for deep-fertilization liquid fertilizer machine’ fertilizer-spraying needle when it came in and went out of the soil, the simulation software of reverse design and kinematics analysis was compiled, which was for pricking hole mechanism of the non-circular gear planetary system . The software avoided the blindness that the obverse design method tried the wrong parameters. By changing the coordinates for some types of value points onstatic trajectory to control fertilizer-spraying needle point posture, the reverse process, simulation result and mechanism motion process were showed intuitively and dynamically, and the optimized parameters were that the gears’ center distance was 61.5 mm, the distance between planetary gear center and fertilizer-spraying needle point was 161 mm, the cave mouth width was 28 mm, the track height was 252 mm and the width was 182 mm. High-speed photography bench was established and tested. The relative motion trajectory of fertilizer-spraying needle point and the key point posture were inspected in the process of actual operation. The results showed that the fertilizer-spraying needle point trajectory height was 246 mm and the width was 188 mm, and the accuracy and feasibility of reverse design and analysis were validated. This study uses many methods such as theoretical analysis mathematics, computer numerical simulation, high speed camera technology and rack experiments, and provides the reference for improving agricultural machinery quality and fertilizer applicator design level.%为更好地满足深施型液态施肥机喷肥针入土垂直度及穴口较小的农艺要求，采用MATLAB GUI开发平台，编写了非规则齿轮行星系扎穴机构的反求设计与运动学分析仿真软件。该软件避免了正求方法试凑参数的盲目性，通过改变静轨迹上若干型值点的坐标，控制喷肥针尖姿态，直观动态地显示出反求过程、结果以及机构仿真运动过程，优化出最佳参数：穴口宽度为28 mm，静轨迹的高度为252 mm、宽度为182 mm。为了验证扎穴轨迹的正确性进行高速摄像试验，观察和分析了实际作业过程中喷肥针尖的相对运动轨迹、关键点姿态。试验结果表明：喷肥针尖轨迹高度246 mm、宽度188 mm，在试验误差允许范围内，轨迹的高度和宽度与理论仿真软件优化结果基本一致，充分验证反求设计分析的准确性和可行性。该研究为扎穴机构的反求设计提供了参考。
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