Autonomous self-burying seed carriers for aerial seeding
Autonomous self-burying seed carriers for aerial seeding
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DOI：
10.1038/s41586-022-05656-3
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发表时间：
2023-02-16
期刊：
影响因子：
64.8
通讯作者：
Yao, Lining
中科院分区：
文献类型：
--
作者：
Luo, Danli;Maheshwari, Aditi;Yao, Lining
飞播可以迅速覆盖大面积和难以到达的地区（1），以改善土壤质量和减少农业中的残留氮（2），并用于火灾后重新造林（3-5）和荒地恢复（6，7）。然而，它遭受低发芽率，由于未埋的种子直接暴露于严酷的阳光，风和食谷鸟类，以及不理想的空气湿度和温度（1，8，9）。在这里，受Erodium种子（10-14）的启发，我们设计和制造自钻孔种子载体，将木材单板变成高度刚性（干燥时约4.9 GPa，潮湿时约1.3 GPa）和具有极大弯曲曲率（1，854 m（-1））的湿态弯曲或盘绕致动器，比文献中的值大45倍（15-18）。我们的三尾载体在两个触发周期后在平地上的钻孔成功率为80%，这是由于其尾部锚定的有益静止角度（25度-30度），而天然的Erodium种子的成功率为0%。我们的载体可以携带各种大小和内容物的有效载荷，包括生物肥料和白皮松大小的植物种子，长度约为11毫米，重量约为72毫克。我们比较实验和数值模拟的数据，阐明曲率变换和驱动机制，以指导种子载体的设计和优化。我们的系统将提高飞播的有效性，以减轻农业和环境压力，并在能源收集，软机器人和可持续建筑方面具有潜在的应用。
Aerial seeding can quickly cover large and physically inaccessible areas(1) to improve soil quality and scavenge residual nitrogen in agriculture(2), and for postfire reforestation(3-5) and wildland restoration(6,7). However, it suffers from low germination rates, due to the direct exposure of unburied seeds to harsh sunlight, wind and granivorous birds, as well as undesirable air humidity and temperature(1,8,9). Here, inspired by Erodium seeds(10-14), we design and fabricate self-drilling seed carriers, turning wood veneer into highly stiff (about 4.9 GPa when dry, and about 1.3 GPa when wet) and hygromorphic bending or coiling actuators with an extremely large bending curvature (1,854 m(-1)), 45 times larger than the values in the literature(15-18). Our three-tailed carrier has an 80% drilling success rate on flat land after two triggering cycles, due to the beneficial resting angle (25 degrees-30 degrees) of its tail anchoring, whereas the natural Erodium seed's success rate is 0%. Our carriers can carry payloads of various sizes and contents including biofertilizers and plant seeds as large as those of whitebark pine, which are about 11 mm in length and about 72 mg. We compare data from experiments and numerical simulation to elucidate the curvature transformation and actuation mechanisms to guide the design and optimization of the seed carriers. Our system will improve the effectiveness of aerial seeding to relieve agricultural and environmental stresses, and has potential applications in energy harvesting, soft robotics and sustainable buildings.