Robot task planning and explanation in open and uncertain worlds by Hanheide, M, Göbelbecker, M, Horn, G, Pronobis, A, Sjöö, K, Aydemir, A, Jensfelt, P, Gretton, C, Dearden, R, Janicek, M, Zender, H, Kruijff, G, Hawes, N, Wyatt, J