Patents by Inventor Ralf Guillaume Jean Catharina Heijkants

Ralf Guillaume Jean Catharina Heijkants has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8909500
    Abstract: Method and system for measuring an angle between a first member and a second member under dynamic conditions is provided. A first and second acceleration sensor and an angle measuring device (goniometer) are connected to the first and second member. Under dynamic and static conditions, the angle (?) is measured by the goniometer. Under static conditions, the inclination angle of the first member is measured using the first acceleration sensor and the inclination angle of the second member using the second acceleration sensor and the angle (??) between the first and second members is calculated. Then the deviation is calculated between the angle (?) and the angle (??). An error correction factor is calculated from the deviation between both angles (?,??). The error correction factor is applied to future and/or previous measurements of the angle (?) between the first and second member done by the goniometer.
    Type: Grant
    Filed: November 3, 2008
    Date of Patent: December 9, 2014
    Assignee: Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO
    Inventors: Ralf Guillaume Jean Catharina Heijkants, Caroline van der Horst, Merijn Wijnen, Marcus Benedictus Hoppenbrouwers
  • Patent number: 8211456
    Abstract: The present invention relates to “grafting to” methods of modifying materials surfaces with high-density polymer brushes. A method of the present invention comprises contacting in succession or simultaneously an activated material surface, a solution of a polymeric material having a polymeric backbone with pendant reactive moieties, and a melt of brush-forming terminally-functionalized polymer chains, in order to allow a covalent bonding reaction to occur between surface and polymers, wherein upon completion of the reaction, the polymeric material forms a layer between the material surface and the brush polymer chains.
    Type: Grant
    Filed: August 16, 2006
    Date of Patent: July 3, 2012
    Assignee: Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO
    Inventors: Joost Hubert Maas, Aafke Tessa Ten Cate, Ralf Guillaume Jean Catharina Heijkants
  • Patent number: 7943678
    Abstract: The invention presents a new method to prepare biomedical polyurethanes with high tensile and tear strengths. Such polyurethanes are especially interesting for making foams thereof, e.g. as meniscus implants. A new method, applicable to the biomedical polyurethanes, has been found to make such foams, that can be used as scaffolds. This method is based on salt leaching and phase separation.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: May 17, 2011
    Assignee: Orteq, B.V.
    Inventors: Ralf Guillaume Jean Catharina Heijkants, Albert Johan Pennings, Jacqueline Hermina De Groot, Ralph Vincent Van Calck
  • Publication number: 20100286950
    Abstract: Method and system for measuring an angle between a first member and a second member under dynamic conditions is provided. A first and second acceleration sensor and an angle measuring device (goniometer) are connected to the first and second member. Under dynamic and static conditions, the angle (?) is measured by the goniometer. Under static conditions, the inclination angle of the first member is measured using the first acceleration sensor and the inclination angle of the second member using the second acceleration sensor and the angle (??) between the first and second members is calculated. Then the deviation is calculated between the angle (?) and the angle (??). An error correction factor is calculated from the deviation between both angles (?,??).
    Type: Application
    Filed: November 3, 2008
    Publication date: November 11, 2010
    Applicant: Nederlandse Organisatie voor toegepast- natuurwetenschappliji onderzoek TNO
    Inventors: Ralf Guillaume Jean Catharina Heijkants, Caroline van der Horst, Merijn Wijnen, Marcus Benedictus Hoppenbrouwers
  • Patent number: 7786326
    Abstract: The present invention relates to a polyacylurethane having the following general formula (I) and a process for the preparation of such polyacylurethane. Preferred embodiments of the polyacylurethanes according to the invention have elastomeric properties. The polyacylurethanes can suitable be used in biodegradable, biocompatible and/or biomedical devices.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: August 31, 2010
    Assignee: Stichting Voor de Technische Wetenschappen
    Inventors: Ralf Guillaume Jean Catharina Heijkants, Arend Jan Schouten, Leendert Willem Schwab, Frans Vincent Roukes, Albert Johan Pennings
  • Publication number: 20090280157
    Abstract: The present invention relates to “grafting to” methods of modifying materials surfaces with high-density polymer brushes. A method of the present invention comprises contacting in succession or simultaneously an activated material surface, a solution of a polymeric material having a polymeric backbone with pendant reactive moieties, and a melt of brush-forming terminally-functionalized polymer chains, in order to allow a covalent bonding reaction to occur between surface and polymers, wherein upon completion of the reaction, the polymeric material forms a layer between the material surface and the brush polymer chains.
    Type: Application
    Filed: August 16, 2006
    Publication date: November 12, 2009
    Inventors: Joost Hubert Maas, Aafke Tessa Ten Cate, Ralf Guillaume Jean Catharina Heijkants
  • Publication number: 20080214771
    Abstract: The present invention relates to a polyacylurethane having the following general formula (I) and a process for the preparation of such polyacylurethane. Preferred embodiments of the polyacylurethanes according to the invention have elastomeric properties. The polyacylurethanes can suitable be used in biodegradable, biocompatible and/or biomedical devices.
    Type: Application
    Filed: July 21, 2005
    Publication date: September 4, 2008
    Inventors: Ralf Guillaume Jean Catharina Heijkants, Arend Jan Schouten, Leendert Willem Schwab, Frans Vincent Roukes, Albert Johan Pennings