A brake assembly comprises: a brake piston configured to be movable for a brake apply or release and having an inner wall forming a piston cavity, wherein a groove is formed on the inner wall of the brake piston; a linearly movable structure positioned within the piston cavity of the brake piston and configured to be linearly movable within the piston cavity; and a resilient material, wherein a part of the resilient material is located within the groove formed on the inner wall of the brake piston and the other part of the resilient material is disposed on an outer surface of the linearly movable structure so that the resilient material is engageable with a surface of the groove formed on the inner wall of the brake piston to move the brake piston by restoring force of the resilient material in response to linear movement of the linearly movable structure.