Optical Design and Performance of the Odin UV/Visible Spectrograph and Infrared Imager Instrument

Sweden\u27s Odin international scientific small satellite is planned for launch into a sun synchronous low earth orbit in 1998. Odin\u27s mission will be both astronomy and atmospheric science (aeronomy). Its principle aeronomy payload is a high performance, lightweight (12 kilograms) ultraviolet/visible imaging spectrograph and infrared imager, that will point at the limb of the earth\u27s upper atmosphere and measure molecular species associated with ozone chemistry, detect aerosols and tomographically measure and map ozone. The Canadian Space Agency is funding this payload, which has the acronym OSIRIS , and Routes Inc. is currently building the flight model. OSIRIS is effectively two optical instruments mounted in a common optical housing and supported by common electronics. The first instrument consists of three infrared telescopes, each with an Indium Gallium Arsenide (InGaAs) linear detector. The second part is a high precision imaging spectrograph with a wavelength range of 280 to 800 nanometers, which uses a UV-enhanced CCD. The imaging spectrograph uses compact reflective optics and an aspheric reflective ruled grating, and provides excellent spectral imaging performance and stray-light rejection. This paper first briefly describes the overall instrument and then describes the optical design and the Development Model optical and sky test performance results. This paper includes a brief description of how OSIRIS will obtain valuable new environmental information on the upper atmosphere, and the requirements this places on the instruments optical design

Sampled-data robot adaptive control with stabilizing compensation

This paper addresses the stability and performance of discretized adaptive control algorithms for robotic manipulator control, and the compensation of these algorithms for improved stability and tracking performance. The discretization of Slotine and Li's direct adaptive control algorithm results in a sampled-data system for which stability has not been guaranteed. By formulating the entire sampled-data system in continuous-time, Lyapunov's direct method is used to determine the stability and to derive a non-linear discrete-time compensating term. This compensator is added to a multi-rate discretization of Slotine and Li's adaptive algorithm, to stabilize the sampled-data system. For sufficiently high gain, globally stable performance and a known bound on the norm of the filtered error is proven. The effect of the compensator and validity of the error bound predictions are demonstrated through simulation and implementation of 2 degree-of-freedom manipulator control

Sampled-data robot adaptive control with stabilizing compensation

This article addresses the stability and performance of discretized adaptive control algorithms for robotic manipulator control and the compensation of these algorithms for improved stability and tracking performance. The discretization of Slotine and Li's direct adaptive control algorithm results in a sampled-data system for which stability has not been guaranteed. By formulating the entire sampled-data system in continuous time, Lyapunov's direct method is used to determine the stability and to derive a nonlinear discrete-time compensating term. This compensator is added to a multirate discretization of Slotine and Li's (1987a) adaptive algorithm, to stabilize the sampled-data system. For sufficiently high gain, globally stable performance and a known bound on the norm of the filtered error is proven. The stabilizing effect of the compensator and validity of the error bound predictions are demonstrated through simulation and implementation of 2-DOF manipulator control