A defense presentation is very different to one you would deliver to a seminar audience. The panel want to confirm that you have made a significant contributio

A defense presentation is very different to one you would deliver to a seminar audience. The panel want to confirm that you have made a significant contribution to the field. They know the field and are unlikely to be swayed by video of robots doing their tricks. A good format might be to present a 5 minute segment to provide an overview of what you have worked on. Then the remainder should focus on reinforcing the contributions that your dissertation also presents. Departing too far from your dissertation might raise more questions which you will then need to defuse during the interrogation. Obviously if your contribution includes something that can be further evidenced by a suitable short video segment, then that will be valuable. For example, if you have developed some algorithm which leads to faster, smoother, etc operations under some adverse condition, then demonstrating it in addition to explaining the theory behind it is of value. BTW, most of us only ever have to defend one PhD.