Method and apparatus for generating a vibrational stimulus

A vibrotactile transducer to provide a vibrational stimulus to a body of a user in response to an electrical input, said vibrotactile transducer comprising;

• a housing having a contacting face with an opening;
• a moving magnetic assembly;
• at least one spring suspending said assembly in said housing;
• a mechanical contactor connected to said magnet assembly for movement therewith, a gap being defined around said contactor between said contactor and said housing when said contactor is positioned in said opening, said contactor and said contacting face of said housing being simultaneously positionable against a surface associated with a user, wherein when said contactor is positioned against said user surface, said contactor and magnet assembly are retracted with respect to said housing to preload said contactor and magnet assembly against the action of said spring;
• and
• a magnetic circuit attached to said housing, said magnetic circuit including electrical coils connected in a push-pull configuration whereby magnetic fields induced by current flowing in said coils vibrates said magnetic assembly said contactor, and said housing,
• wherein said contactor vibrates within the opening of the housing to provide a contactor vibration to said user surface, said housing vibrates to provide a housing vibration, said housing vibration being at a reduced level and substantially out of phase relative to said contactor vibration, and a mass of said contactor and said magnetic assembly is approximately 20% to 40% of a total mass of said transducer.

A method for providing a vibrational stimulus to a body of a user in response to an electrical input, said method comprising the steps of:

• providing a vibrotactile transducer having a substantially cylindrical housing with a substantially circular contacting face with an opening passing therethrough, said housing being defined by a height of said housing and a diameter of said contacting face, said diameter being greater than said height, a moving magnetic assembly, at least one spring suspending the assembly in said housing, a mechanical contactor connected to said magnetic assembly for movement therewith and positioned in said opening for vibratory movement through said opening, a gap being defined around said contactor between said contactor and said housing when said contactor is positioned in said opening, and a magnetic circuit attached to said housing, said magnetic circuit including electrical coils connected in a push-pull configuration whereby magnetic fields induced by current flowing in said coils vibrates said magnetic assembly, said contactor, and said housing;
• positioning said contacting face and said mechanical contactor simultaneously against a surface associated with a user, causing said mechanical contactor to retract within said opening;
• and
• operating said magnetic circuit and vibrating the magnetic assembly and the mechanical contactor, said contactor vibrating within the opening of the housing to provide a contactor vibration to said user surface, and said housing vibrating to provide a housing vibration, said housing vibration being at a reduced level and substantially out of phase relative to said contactor vibration.

A wearable device comprising a plurality of vibrotactile transducers mounted on said wearable device, said vibrotactile transducers providing a vibrational stimulus to a body of a user in response to an electrical input, each of said vibrotactile transducers comprising:

• a substantially cylindrical housing having a substantially circular contacting face, said contacting face defining an opening passing therethrough, said housing being defined by a height of said housing and a diameter of said contacting face, said diameter being greater than said height;
• a moving magnetic assembly;
• at least one spring suspending said assembly in said housing;
• a mechanical contactor connected to said magnet assembly for movement therewith, a gap being defined around said contactor between said contactor and said housing when said contactor is positioned in said opening, said contactor and said contacting face of said housing being simultaneously positionable against a surface associated with a user, wherein when said contactor is positioned against said user surface, said contactor and magnet assembly are retracted with respect to said housing to pre-load said contactor and magnet assembly against the action of said spring;
• and
• a magnetic circuit attached to said housing, said magnetic circuit including electrical coils connected in a push-pull configuration whereby magnetic fields induced by current flowing in said coils vibrates said magnetic assembly, said contactor, and said housing,
• wherein said contactor vibrates within the opening of the housing to provide a contactor vibration to said user surface, and
• said housing vibrates to provide a housing vibration, said housing vibration being at a reduced level and substantially out of phase relative to said contactor vibration.