Parallel robots are capable of high-speed manipulation and have become essential tools in the industry. The proximal placement of their motors and the low weight of their end effectors make them ideal for generating highly dynamic motion. Therefore, parallel robots can be adopted for motion platform designs, as long as end effector loads are low. Traditional motion platforms can be large and powerful to generate multiple g acceleration. However, these designs tend to be expensive and large. Similar but smaller motion platforms feature a small work range with reduced degrees of freedom (DoFs) and a limited payload. Here we seek a medium-sized affordable parallel robot capable of powerful and high-speed 6-DoF motion in a comparably large workspace. This work explores the concept of a quadruped robot flipped upside-down, with the motion platform fixed between its feet. In particular, we exploit the high-power dynamic brushless actuation and the four-leg redundancy when moving the motion platform. We characterize the resulting motion platform by tracking sinusoidal and circular trajectories with varying loads. Dynamic motions in 6 DoFs up to 10 Hz and ~10 mm amplitude are possible when moving a mass of 300 grams. We demonstrate single-axis end-effector translations up to ~20 mm at 10 Hz for higher loads of 1.2 kg. The motion platform can be replicated easily by 3D printing and off-the-shelf components. All motion platform-related hardware and the custom-written software required to replicate are open-source.
翻译:颠倒式:经济高性能运动平台
翻译后的摘要:
平行机器人具有高速操纵能力,已成为工业中必不可少的工具。其电机的近端放置和末端执行器的轻量化使其理想地产生高动态运动。因此,只要末端效应负载较低,就可以采用平行机器人进行运动平台设计。传统运动平台可能很大且强大,可以产生多个g的加速度。但是,这些设计往往昂贵且庞大。类似但更小的运动平台具有较小的工作范围、减少的自由度和有限的有效载荷。在这里,我们寻求一种中型且经济实惠的平行机器人,其能够在相对较大的工作空间内实现强大且高速的6自由度运动。本文探索了一种四足机器人“颠倒过来”,其运动平台位于它的脚之间。特别是,我们利用高功率动态无刷电机和四条腿的冗余来移动运动平台。我们通过跟踪负载变化的正弦和圆形轨迹来表征所得到的运动平台。当移动质量为300克的物体时,可以实现多达10 Hz和约10毫米的6自由度动态运动。当货物量更大时,例如1.2公斤时,可以实现单轴末端执行器的最大平移量达到约20毫米/10 Hz。本运动平台可以通过3D打印和现成组件轻松复制。所有与运动平台相关的硬件和自定义编写的软件均为开源。