Here’s an App note from Precision Microdrives on EMI from vibration motors and their Electromagnetic compatibility. Link is here
Electromagnetic interference (EMI) is the radiation or induction of electromagnetic noise on a system. DC motors are a common source of EMI, as are most electromagnetic circuit components. They are potential sources of noise and can generate common-mode currents. EMI can result in degraded performance, data corruption, or if strong enough can cause the system to fail completely. EMI can be radiated or conducted comes from magnetic and electrical sources, respectively. In the case of DC motors, both radiated and conducted emissions are present.