  We present a study of experimental determination of the Wtb anomalous
couplings in the $t\bar{t}$ process at the International Linear Collider in the
framework of effective field theory. The theory predicts several observables
that are particularly sensitive to the couplings including the asymmetry of the
bottom quark angular distributions. These observables require excellent
identification capabilities for the b quark in a detector. We describe tools
needed for the identification with particular emphasis on determination of the
quark charge and b-tagging together with generic selections for the $t\bar{t}$
events. The focus of the study is on the all hadronic decay channel which
provides the largest statistics. In the study we demonstrate advantages of the
clean environment of the ILC that allow a precise measurement of the
observables. We also explain how this process can be used for optimisation of
ILC detector in the context of the SiD detector concept
