RESEARCH ON MOTION ANALYSIS SYSTEM FOR 3-DIMENSIONAL SPACE ROBOT USING PERSONAL COMPUTER NETWORK

在本研究中，我们利用局域网连接的多台个人计算机，研究了一个空间机器人三维运动模拟器。与使用UNIX的传统模拟器相比，该模拟器具有相同的性能，并实现了成本的降低。首先，建立了三维柔性空间机器人的N阶非递归拉格朗日方程，其中N为机器人体数。这些方程减少了运动方程的计算次数，在个人计算机并行计算系统中起着重要的作用。此外，非递归方程可以分离为每个体的一个方程。这意味着可以通过并行处理同时计算每个物体的方程。其次，构建并行处理系统。考虑了一种轨道空间机器人系统，该系统由空间平台和双连杆机械臂组成。尸体的数量是3。我们用一台个人电脑做服务器，用三台电脑做客户端。一个客户计算一个身体的方程式。首先，每个客户端计算方程中的非线性项和控制力矩。这些结果被发送到服务器。服务器通过乘以一个逆质量矩阵来计算每个角加速度，并将它们发送给每个客户端。然后，计算机器人的角度和角速度。这是一个周期内的计算序列。经过验证，该仿真器与使用一台UNIX机器的传统仿真器相比，实现了相同的计算时间和精度。另一方面，系统的价格变成了UNIX机器的五分之一。我们使用Linux作为操作系统。

In this research, we have studied a space robot simulator for three-dimensional motion using several personal computers connected by LAN. This simulator had same performance and realized to reduce its cost comparing conventional simulators using a UNIX machine. First of all, we developed non-recursive Lagrange equations with order N for three-dimensional flexible space robot, where N denotes the number of robot bodies. These equations play very important role in parallel computing system with personal computers, because they reduce calculation times of equations of motion. Moreover, non-recursive equations can be separated to an equation for each body. It means that each body's equation can be calculated by parallel processing at the same time. Next, we constructed parallel processing system. We considered a space robot system in an orbit, which consists of a space platform and a two-link manipulator. The number of bodies is three. We used one personal computer for the server and three computers for clients. One client calculates one body's equation. First of all, each client calculates non-linear terms and control torque in equations. These results are sent to the server. The server calculates each angular acceleration by multiplying an inverse mass matrix and sent them to each client. Then, angle and angular velocity of a robot are calculated. These are calculation sequence in one cycle. We confirmed that this simulator realized same calculation time and the accuracy comparing with conventional simulator using one UNIX machine. On the other hand, the price of the system became one fifth of the UNIX machine. We used Linux for OS.