BASIC STUDY ON AN AGRICULTRAL WALKING VEHICLE

本研究旨在观察行走机构在农用运输车上的应用能力。在给定的研究周期内完成了以下工作：1.行走车辆机构的确定。根据前人对步行机器人的研究，我们确定了步行机器人的腿数为4条，每条腿的自由度数为3个。腿部采用了受电弓机构。我们设计了一辆采用单元结构的样车。在对初始模型进行步行实验后，我们对更强大的运动单元进行了改装，以进行身体抬高。通过试错法找到了与波浪步态基本一致的四足步行步态。3.对控制系统和行走模式进行了讨论。我们为车载计算机系统开发了一个电机控制程序。改装后的步行车直线行走速度约为0.23 cm/s。我们进一步…更实现了车辆的侧向行走和旋转行走。此外，我们增加了一些传感器来测量分布的人体载荷和人体倾斜角，结果表明C.G.的平移必须考虑来自称重传感器系统的信息反馈。4.对周围环境状态检测的讨论。首次将超声波传感器应用于检测平面、沟槽表面和台阶的能力。结果表明，超声波传感器的应用不适合环境的突变。后来，我们应用立体图像处理系统来测量土壤表面特定点的长度。我们发现该系统将适用于步行车辆系统。5.总结。我们已经开发了一种试验性的步行车。在未来的农业中，特别是在没有铺路的常规农机的情况下，可能会有应用的机会。进一步的研究不仅应集中在平坦地形上的应用步行，还应包括坡面上的步行。较少

This research has been done to observe the capability of applying a walking mechanism to the agricultural transportation vehicle. The following items were done during the given period of study.1.Decision of mechanism for a walking vehicle. Based on some information from previous studies on walking robots, we have decided the number of leg to be 4, the number of DOF per leg is 3. We employed the pantograph mechanism for the leg.2.Manufacturing of experimental walking vehicle. We have designed a prototype vehicle where the unit structure was employed. After walking experiment for initial model, we modified more powerful motor unit for body elevation. Quadruped walking gait was found by try-and-error method which turned out to be almost the same as wave gait.3.Discussion on control system and walking pattern. We have developed a motor-control program for mounted computer system. By using the modified walking vehicle, the walking velocity was about 0.23cm/sec for straight walk. We further … More realized the lateral walking and the rotational walking by our vehicle. Moreover, we added some sensors to measure distributed body load and body gradient angle and results showed that the translation of C.G. must be done by considering the feedback of information from the load cell systems.4.Discussion on surrounding environmental status detection. Ultrasonic sensor was firstly applied to check the capability of detecting plane surface, grooved surface and step. The result told us that the application of ultrasonic sensor is not suitable for sudden change of environments. Later, we applied the stereo image processing system to measure the length of particular point on a soil surface. We found that this system will be applicable to the walking vehicle system.5.Summary. We have developed an experimental walking vehicle. In future agriculture, there may be the chance of application especially in the situation of no-paved road conventional agricultural machinery. Further research should be concentrated on the applied walking on not only flat terrain but also on the slope. Less