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18 mm-sized Orionid meteoroids were captured in 2019 and 2020 by the CanadianAutomated Observatory's mirror tracking system. Meteor position measurementswere made to an accuracy of $\sim1$ m and the meteors were tracked to alimiting magnitude of about $+7.5$ at the faintest point. The trajectoryestimation shows the intrinsic physical dispersion of the Orionid radiant is$0.400^{\circ} \pm 0.062^{\circ}$. An erosion-based entry model was fit to theobservations to reproduce ablation and fragmentation for each meteor,simultaneously reproducing the light curve, the dynamics, and the wake. Wakeobservations were found to directly inform the grain mass distribution releasedin the modelled erosion. A new luminous efficiency model was derived fromsimultaneous radar and optical observations and applied in the modelling toimprove its accuracy. The results show that the apparent strength of Orionidsvaries with radiant location and time of appearance during the period of showeractivity. The average differential grain mass distribution index was 2.15,higher than found from in-situ estimates, possibly due to the evolution of thephysical properties of meteoroids since ejection. All Orionids showed leadingfragment morphology which was best explained by stopping the erosion at thepeak of the light curve, leaving a non-fragmenting meteoroid with $\sim10\%$ ofthe original mass. The inverted Orionid meteoroid average bulk density of$\sim300$ kg m$^{-3}$, corresponding to porosities of $\sim90\%$, is consistentwith in-situ measurements of larger dust particles by Vega-2 at 1P/Halley andRosetta at 67P.

First holistic modelling of meteoroid ablation and fragmentation: A case study of the Orionids recorded by the Canadian Automated Meteor Observatory