4 research outputs found
Cheetah-cub-S: Steering of a Quadruped Robot using Trunk Motion
In Cheetah-cub-S we realized an efficiant concept by implementing a spine-like structure with one DoF into a quadruped, modular and mobile platform. We increased maneuverability dramatically compared to a robot with rigid spine, while keeping controlling effort low by using intelligent mechanics. Therefore, it is possible to steer via trunk motion without changing the gait or corresponding parameters. The robot weights 1160 g at 0.1 m (height), 0.105 m (width) and 0.205 m (length). Based on qualitative tests, it is able to run 0.36 m/s and turn within a radius of 0.51 m (equivalent to 2.48 body lengths) at 0.31 m/s (equivalent to 34/s). Furthermore, we could steer the quadruped around three objects in a 7.13 m (23 s at 0.31 m/s) slalom within our test area. Due to its modularity, Cheetah-cub-S is a versatile mobile platform and components such as the spine segment, legs, motors or steering mechanism can be exchanged
Proverb: The Probabilistic Cruciverbalist
We attacked the problem of solving crossword puzzles by computer: given a set of clues and a crossword grid, try to maximize the number of words correctly filled in. After an analysis of a large collection of puzzles, we decided to use an open architecture in which independent programs specialize in solving specific types of clues, drawing on ideas from information retrieval, database search, and machine learning. Each expert module generates a (possibly empty) candidate list for each clue, and the lists are merged together and placed into the grid by a centralized solver. We used a probabilistic representation throughout the system as a common interchange language between subsystems and to drive the search for an optimal solution. Proverb, the complete system, averages 95.3% words correct and 98.1% letters correct in under 15 minutes per puzzle on a sample of 370 puzzles taken from the New York Times and several other puzzle sources. This corresponds to missing roughly 3 words or 4 l..