Dr Wilkins joined CSIRO in 1975 as a Research Scientist after spending a year in the Physics Department, Imperial College, London, as a Sir Arthur Sims Postdoctoral Fellow. He was promoted to Senior Research Scientist in 1983 Principal Research Scientist in 1990, and Chief Research Scientist in 1998. In 1999, Dr Wilkins was appointed Honorary Professor, Department of Physics, Monash University (now School of Physics and Materials Engineering).

Dr Wilkins's research interests include various theoretical and experimental aspects of X-ray diffraction and imaging, as well as the design of new X-ray instruments (e.g. BigDiff installed at the Photon Factory, Tsukuba, Japan). Dr Wilkins holds over six international patents filed in the area of X-ray optics and imaging. Some of these are key patents in relation to the formation and commercial activities of XRT Limited, a CSIRO spin-off company. Dr Wilkins is the leader of the CSIRO team that has been active in developing novel methods of X-ray imaging, particularly those involving phase-contrast, using both conventional and synchrotron sources.

Dr Wilkins is a co-editor of the Journal of Synchrotron Radiation (Munksgaard, Copenhagen) and also the Journal of X-Ray Science & Technology. He was Chairman of the Commission on Synchrotron Radiation of the International Union of Crystallography from 1999–2002, and is a Member of the National Committee for Crystallography, and the National Committee for Physics of the Australian Academy of Science. He is also a member of the National Scientific Advisory Committee (NSAC) for the Australian Synchrotron, and Chair of the ChemMatCARS Sub-committee for the Australian Synchrotron Research Program.

In 1997, Dr Wilkins was awarded the Walter Boas Medal of the Australian Institute of Physics (shared). Dr Wilkins was also a recipient of the CSIRO Medal in 1998, as leader of the CSIRO team responsible for the development of hard X-ray phase-contrast imaging using conventional sources.