The application of Aiki in the Aikido techniques demonstrated by Morihei Ueshiba is analysed below. 

In this video between the times 1.59 to 2.18 and 2.21 to 2.34 Tori applies Aiki by first offering the target to Uke and then, as Uke steps forward to make contact, he withdraws the target. This induces Uke to reverse the muscle torque about the ankle joint of his front foot to maintain his forward momentum to follow the target. This action unbalances Uke to the front. Aiki-Feint