incomplete PhD

My PhD research is finished. Almost finished. Almost, only because one of my supervisors- who does not really have any plan what goal he is trying to achieve other than publishing papers- is pushing for one more paper by asking me to do something which is essentially a repetition of what I have already done, but in a somewhat new fashion: I have pushed a micro object precisely along a desired trajectory and have shown that adaptive controllers using artificial intelligence can accomplish this task. He asks me to repeat this work to push multiple objects as a proof of concept for micro-assembly, i.e. we can automate the process of positioning different micro objects. At this moment, I don't have any motivation to do that, although it may only take 1 or two months of work to finish that task and get the degree. I tried to convince that supervisor that it is essentially the same piece of research we have done already and that really does not change anything in terms of doing something novel, but he insists that without doing that, he would not consider my work as "complete" and hence I can not defend my PhD.
Anyways, doing something which I do not deem of any immediate value is really hard for me, especially when I have tens of more interesting things to do. So at this point, I keep myself busy doing things I love, rather than those I am supposed to do because of some external force.

PS: You will soon (in a few weeks or months) will read an interesting post here about my ancestry profile and my genealogy. I am only waiting for the price to drop off or I get a bit richer to order this DNA test. I see a tremendous potential for clinical knowledge advancement if more users around the world take the test. Exciting, isn't it?