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Amazon.com has introduced the Simple Storage Service (S3), a commodity-priced storage utility. S3 aims to provide storage as a low-cost, highly available service, with a simple 'pay-as-you-go' charging model. This article makes three contributions. First, we evaluate S3's ability to provide storage support to large-scale science projects from a cost,(More)
The sea robot-assisted inspection (Sea-RAI) marsupial robot team is the first known manportable unmanned surface vehicle (USV) that hosts an unmanned aerial vehicle (UAV). The Sea-RAI is designed for inspecting littoral environments for military, environmental, and disaster-response applications. The project also provides a platform for exploring the four(More)
Software systems that are successfully deployed and used seem to always have a longer lifetime than was originally expected. It is also common knowledge that the cost of maintaining and evolving those systems during that lifetime dwarf the initial cost of creating the system. This makes support for self-management in the legacy software arena all that much(More)
Future improvements in hardware and O/S support for monitoring programs will depend on providing feedback for current support (even if it is quite limited). We look at using hardware breakpoint registers and performance counters in order to trace data accesses in a program. We first present a small experiment to understand how these features can be used to(More)
Biological studies on animal walking and running have contributed to the control of mobile robots. Taking inspiration from such studies, a hybrid impulse-position (HIP) controller has been developed for legged locomotion over uneven terrain. The HIP controller generates joint torques during the stance phase of each leg cycle to propel and stabilize the(More)
Data breakpoints, sometimes called watchpoints, have long been desirable for debugging and other dynamic analyses, but are often prohibitively slow to use. Current processors have a small number of breakpoint registers that can be used to trap data read and write operations at CPU speeds—for example, the Intel 386+ CPUs have four breakpoint registers that(More)
A Force Threshold-based Position (FTP) controller is presented for cyclic legged locomotion over irregular terrain. Force feedback in the form of threshold comparison is used to control each leg independently. The FTP controller decouples the control of individual legs and uses only localized feedback to generate joint torques. No feedback of body state is(More)
A wheelchair-mounted robotic arm (WMRA) system was designed and built to meet the needs of mobilityimpaired persons with limitations of upper extremities, and to exceed the capabilities of current devices of this type. The control of this 9-degree-of-freedom system expands upon conventional control methods and combines the 7-DoF robotic arm control with the(More)
Biological studies have contributed to the control of mobile robots. Studies from the field of neuroscience to the field of psychology have shown roboticists different ways to control mechanical devices. A number of studies pertaining to human reaching and grasping have been done in the past few decades. These studies provide the psychological and(More)