The InfraRed Imaging Spectrograph (IRIS) will be a first-light client instrument for the Narrow Field Infrared Adaptive Optics System (NFIRAOS) on the Thirty Meter Telescope. IRIS includes three configurable tip/tilt (TT) or tip/tilt/focus (TTF) On-Instrument Wavefront Sensors (OIWFS). These sensors are positioned over natural guide star (NGS) asterisms using movable polar-coordinate pick-off arms (POA) that patrol an approximately 2-arcminute circular field-of-view (FOV). The POAs are capable of colliding with one another, so an algorithm for coordinated motion that avoids contact is required. We have adopted an approach in which arm motion is evaluated using the gradient descent of a scalar potential field that includes an attractive component towards the goal configuration (locations of target stars), and repulsive components to avoid obstacles (proximity to adjacent arms). The resulting vector field is further modified by adding a component transverse to the repulsive gradient to avoid problematic local minima in the potential. We present path planning simulations using this computationally inexpensive technique, which exhibit smooth and efficient trajectories.
翻译:红外成像分光谱仪(IRIS)将是三十米望远镜上近距离红外红外调频光学系统(NFIRAOS)的首亮客户工具,它包括三种可配置的小脚/板(TT)或小脚/板/焦点(TTF)在仪器波形前传感器(OIWFS)上。这些传感器位于使用移动极坐标接击臂(POA)对大约2分钟环形视场(FOV)进行巡逻的自然导星(NGS)射线器(NGS)上。 POA能够相互碰撞,因此需要一种协调动作的算法,以避免接触。我们采取了一种方法,即使用一个具有向目标配置(目标恒星的位置)的梯度偏移和避免障碍(靠近相邻臂)的反向部件(POA)的自然导线(POA)上。由此形成的矢量场进一步修改,将一个部件反向反向反向反向视野(FOV)外移动,从而避免进行接触。我们目前采用这种高压式的模型模拟,从而避免了当地微变式模型,从而避免了当地的微变现,从而避免了这种方法,从而避免了本微变现式的微变现式的微变式的微变式的微变式的模拟,我们式的微变式的模拟,从而避免了这种技术。