Wanted: a dead man's switch to transfer from cold storage to an exchange

Upon my death or incapacity I would prefer my Bitcoin to be transferred from my cold wallet to an exchange. From there, my heirs would be able to gain custody through the traditional legal system.

Is there a way to create a time-locked transaction sending my cold storage to a pre-determined exchange address that I periodically (say, once every 12 months) cancel/update to indicate that I am actually alive and that my Bitcoin should not be transferred to the exchange?