Development of GPS aided virtual vision system to prevent disasters in the snow removal operation of Shiretoko pass

为了保证重型机械在经过世界遗产登记的七子半岛的七子山口积雪超过7米的地方进行除雪作业的安全性，开发了高精度RTK-GPS三维虚拟视觉系统。在2004财政年度，该系统的原型被制造出来。在当年降雪前，利用RTK-GPS采集了Shiretoko山口附近的几何数据，并于2005年4月在同一地点进行了试验作业。在数据密度约为每平方米1个数据的区域内，系统的当前位置可以很好地显示在虚拟图像上。但在数据密度较粗的区域，当前位置不能正确显示。之后，在2005财年，虚拟视觉系统的三维可视化质量和可用性得到了提高。此外，在降雪之前，采集了知子山口周围的精细几何数据，并再次进行了测试操作。此次试验在试验区跨度约1Km的范围内取得了良好的效果。然而，由于固定RTK-GPS的位置解码错误通过无线发送到重型机上的移动RTK-GPS，系统在弯道以外的山后隐藏区域无法正常工作。在我们研究所所在的北上市，公共使用的固定RTK-GPS的位置解码误差很容易通过便携式终端获得。因此，在自动扫雪机的轨迹控制和二维虚拟视觉的可视化中，可以很容易地获得位置解码误差，就像雪子无线的情况一样。然而，在Shiretoko关口没有便携式终端设备，建立从固定RTK-GPS发送位置解码误差的方法是需要解决的主要问题。在目前的验证试验中，还明确了该系统对重型机械（电动铲）旋转运动的跟踪特性，并明确了用于感应方向的数字罗盘受重型机械巨大金属质量的影响，在方向读数上存在轻微误差。在未来的发展中，需要在重型机械上安装两个RTK-GPS系统，以获得重型机械的精确定位和精确倾斜。4月7日和8日，将最新研制的系统带到了七子山口的除雪作业现场，并进行了试运行。该系统能够非常精确地显示积雪下的道路，并证明了该系统在实际应用中的能力。在今后的发展中，使系统一键启动，使不熟悉GPS系统的重型机械操作员也能方便地使用该系统，具有十分重要的意义。少

In order to provide safety in the snow removal operation with heavy machine at the site of over 7m of snow accumulation in the Shiretoko pass which go through the word heritage registered Shiretoko peninsula, 3D virtual vision system by means of high precision RTK-GPS was developed. In the fiscal year of 2004, a prototype of the system was made. Before snow fall of the year, geometrical data around the Shiretoko pass were taken by RTK-GPS, and test operations were conducted at the same site on the April of 2005. In the region of data density approximately 1 data per square meter, present location of the system was shown on the virtual image in good accuracy. However in the region of coarse data density, present location was not shown correctly. After that, in the fiscal year of 2005, the quality of 3D visualization of the virtual vision system and usability were improved. Also, before the snow fall, fine geometrical data around the Shiretoko pass were taken and the test operations were … More conducted again. This time, the test operations shown good results in the approximately 1Km span of the test region. However, since the position decode error at the fix RTK-GPS is sent to the mobile RTK-GPS aboard the heavy machine by wireless, the system did not work correctly at the hiding region behind hill beyond a curve. In Kitami city, where our institute is located, the position decode error at the fixed RTK-GPS in public use is easily obtained by a portable terminal. Therefore, in the trajectory control of the automatic snowplow and visualization of 2D virtual vision, the position decode error can be obtained with out trouble like the case of wireless in Shiretoko. However, the portable terminal facility is not available in Shiretoko pass, and establishment of the way of sending position decode error from the fixed RTK-GPS is major task to be solved. Up to date in the proof tests, follow up characteristics of the system to rotating motion of the heavy machine (Power shovel) is also clarified, and it became clear that the digital compass for sensing the orientation is affected by the huge metallic mass of the heavy machine and gives slight error in the orientation reading. In the future development, two RTK-GPS system should be mounted on the heavy machine to obtain not only precise orientation but also precise inclination of the heavy machine. On April 7th and 8th, the latest developed system was brought to the site of snow removal operation in Shiretoko pass, and test operations were conducted. The system was able to show the road buried under the snow very precisely, and the system is proofed to be capable in practical use. In the future development, it is very important to make the boot up of the system by one push of button so that the heavy machine operator unfamiliar with the GPS system can use the system easily. Less