The invention provides wearable devices for effecting transcranial magnetic stimulation to be used by patients who have suffered brain injuries. Permanent magnets are shifted or rotated to deliver a time-varying magnetic field, preferably about the locus of the injury. In an embodiment, the strong magnetic fields of the permanent magnets are directed to the injured area for therapeutic purposes. A novel mechanism is provided that uses a small battery-powered electromagnet to interact with the weak peripheral magnetic fields of the permanent magnets and to shift the permanent magnets between two or more stable positions. As a result, a lightweight, quiet, wearable device with low power consumption is provided.
Time-varying magnetic field therapy using multistable latching mechanisms