Hypothetically, if police caught your periodic-vibration setup in action, and figured out what it's meant for, and found some kind of evidence that you had just

Hypothetically, if police caught your periodic-vibration setup in action, and figured out what it's meant for, and found some kind of evidence that you had just recently created this setup, and turned it on before leaving the house and (according to other evidence) committing a homicide… Well, I don't know about "ironclad", but it would be circumstantial evidence that you were trying to cover something up, which in combination with other evidence might be able to establish premeditation.