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Spotlight
The Roasted Tomato Challenge
CAITLIN LAGRAND and MICHIEL VAN DER MEER, are bachelor’s student Artificial Intelligence, Faculty of Science UvA.
→ Robots, robots everywhere… certainly seems to be the trend at the moment. We know them from car production lines and other industrial applications, but their use in human service situations such as healthcare, care for the elderly or in education are areas of great current interest. In the Robotics Lab of the Informatics Institute of the UvA, we have recently developed a benchmark to test how well a commercially available humanoid robot (Nao) can support humans in a domestic environment. In our test, the Nao robot starts searching a kitchen environment for a tomato: a red circular object. We tested three different algorithms for recognising the tomato: firstly, searching for red objects that are somewhat circular, secondly for circular objects that are mostly red, and thirdly by a colour-blind method inspired by cognitive image processing (a psychological theory on how humans
understand images). In the end, searching for red objects that are somewhat circular proved to be the most successful tomato-finding method. This proof of concept included testing not only the detection of the tomato, but also all steps required to enable the robot to pick up a tomato such as approaching, planning a pick-up without disturbing other nearby objects and the execution of the final pick up, after which the robot is ready to put the tomato into the pan to make dinner. Next, we extended this study to include a method to distinguish different ingredients commonly found in the kitchen. This year, a new student team has been formed at the UvA, which will take these newly learned kitchen skills and compete in RoboCup@ Home (robocupathome.org), the largest international annual competition for autonomous service robots. Ω
→ Reference C. Lagrand, M. van der Meer, A. Visser, The Roasted Tomato Challenge for a Humanoid Robot. Proceedings of the IEEE International Conference on Autonomous Robot Systems and Competitions (ICARSC), 341-346, Bragança, Portugal (2016). → Check out www.dutchnaoteam.nl to see more of what our Nao's can do!
Extinction on islands
JULIA HEINEN is Master’s student Biological Sciences, track Ecology & Evolution, UvA.
→ Reference J.H. Heinen, Master’s thesis, University of Amsterdam (2016). More information: www.juliaheinen.nl/research-poster
→ When humans first arrived on remote oceanic islands, they encountered animals that occurred nowhere else in the world, such as the dodo or giant tortoises. Unfortunately, this sometimes led to extinction of these species because they were eaten by hungry sailors or even their ship rats (Fig. A). This has in turn affected the plants these animals interacted with. For example, birds, mammals and reptiles that ate fruit could disperse the seeds of plants to new areas, especially if they were large or able to fly. There was no overview of animals that went extinct on islands or their characteristics available. Yet, if the characteristics that make animals vulnerable to extinction are known, measures can be taken to prevent new extinctions. Therefore, during my Biology Master’s project at UvA (supervised by W.D. Kissling), I made a database of 1183 fruit-eating animals that have gone extinct or still occur on 74 islands worldwide, and added their weight (1.4
g – 250 kg) and ability to fly to the database. I wanted to find out (1) if some island animals have been more vulnerable to extinction than others and (2) if there have been more extinctions on certain types of islands. From the first statistical model I made, the conclusion could be drawn that large animals have gone extinct most often, especially large birds that were unable to fly (Fig. B), such as the dodo. The loss of large species has caused the mean weight of all fruit-eating animals on islands to be reduced by 37%. Consequently, many large seeds cannot be swallowed and dispersed anymore because only small animals have remained. The second model showed that remote and small islands have had more extinctions than those that are large and closer to mainland. Islands have been impacted in a way that will likely have severe consequences for seed dispersal; they need strong conservation and restoration efforts, especially on small and isolated islands. Ω
↓ Figure (A) The Dutch causing extinctions of flying and flightless birds in Mauritius (De Bry’s Variorum Navigatiornis, 1601). (B) Relationship between size and extinction probability for flying and flightless island birds.