What do you mean by "Middle Ages" in the historical context of the Indian subcontinent?

I know that by the 1600s and 1700s, most Indian Prices would accompany their troops on campaign if it was logistically feasible to do so, and if they felt the political situation commanded allowed it, and they were in good enough health to do so. That said, it would unusual for a Raja to actually be at the head of his troops -- one of his sons or lieutenants would do that, with the Raja at the back acting as a strategist. But this is mainly for the medium-to-smaller princely states in the Late Mughal era. I'm not really sure how similar or different things were a thousand years ealier.

In the case of the Chola Empire of southern India, I'm fairly certain that the king or emperor himself did not accompany an overseas expedition in person, but appointed one of his sons or nephews as the expedition commander.