Road paver with a radar-based leveling device and control method

Abstract

A road paver according to the disclosure comprises a material hopper for receiving paving material and a screed for compacting paving material that is supported with towing arms on a chassis of the road paver. In addition, a radar sensor unit is provided that is configured to measure the distances between the radar sensor unit and at least two ground positions. A control unit of the road paver is configured to adjust a position of the screed relative to the chassis based on the distances measured. In addition, a corresponding method for controlling a road paver is specified.

What is claimed is: 
     
         1 . A road paver comprising:
 a chassis;   a material hopper for receiving paving material;   a screed for compacting paving material supported with towing arms on the chassis;   a radar sensor unit that is configured to measure distances between the radar sensor unit and at least two ground positions; and   a control unit which is configured to adjust a position of the screed relative to the chassis based on the distances measured.   
     
     
         2 . The road paver according to  claim 1  wherein the at least two ground positions are located on a common straight line that is parallel to a paving direction of travel of the road paver. 
     
     
         3 . The road paver according to  claim 1  wherein the radar sensor unit is mounted to a mast attached to the chassis, one of the towing arms, or the screed. 
     
     
         4 . The road paver according to  claim 3  wherein the mast is oriented vertically. 
     
     
         5 . The road paver according to  claim 1  wherein the radar sensor unit comprises a radar sensor which is pivotable between at least two measuring positions for measuring the distances between the radar sensor unit and the at least two ground positions. 
     
     
         6 . The road paver according to  claim 1  wherein the radar sensor unit comprises a radar sensor with an antenna and a radome, wherein the radome is configured to focus beams emitted by the antenna, and the radome is pivotable between at least two measuring positions in which the beams are respectively focused onto different ones of the at least two ground positions. 
     
     
         7 . The road paver according to  claim 1  wherein the radar sensor unit comprises a radar sensor with an antenna and a dielectric lens, and wherein the dielectric lens is configured to focus beams emitted by the antenna, and the dielectric lens is pivotable between at least two measuring positions in which the beams are respectively focused onto different ones of the at least two ground positions. 
     
     
         8 . The road paver according to  claim 1  wherein the radar sensor unit comprises at least two radar sensors being at fixed angles to each other and which are each adapted to measure the distance between the radar sensor unit and one of the at least two ground positions. 
     
     
         9 . The road paver according to  claim 1  wherein the control unit or the radar sensor unit is configured to average the distances measured between the radar sensor unit and the at least two ground positions. 
     
     
         10 . A method for controlling a road paver with a material hopper for receiving paving material and a screed for compacting paving material that is supported with towing arms on a chassis of the road paver, the method comprising:
 measuring with a radar sensor unit provided on the road paver distances between the radar sensor unit and at least two ground positions; and   adjusting with a control unit a position of the screed relative to the chassis based on the distances measured.   
     
     
         11 . The method according to  claim 10  wherein the at least two ground positions are located on a common straight line that is parallel to a paving direction of travel of the road paver. 
     
     
         12 . The method according to  claim 10  wherein the radar sensor unit is mounted to a mast attached to the chassis, one of the towing arms, or the screed. 
     
     
         13 . The method according to  claim 12  wherein the mast is oriented vertically. 
     
     
         14 . The method according to  claim 10  wherein the radar sensor unit comprises a radar sensor, and wherein the measuring comprises pivoting the radar sensor between at least two measuring positions for measuring the distances between the radar sensor unit and the at least two ground positions. 
     
     
         15 . The method according to  claim 10  wherein the radar sensor unit comprises a radar sensor with an antenna and a radome, wherein the radome focuses beams emitted by the antenna, and wherein the method comprises pivoting the radome between at least two measuring positions in which the beams are respectively focused onto different ones of the at least two ground positions. 
     
     
         16 . The method according to  claim 10  wherein the radar sensor unit comprises a radar sensor with an antenna and a dielectric lens, wherein the dielectric lens focuses beams emitted by the antenna, and wherein the method comprises pivoting the dielectric lens between at least two measuring positions in which the beams are respectively focused onto different ones of the at least two ground positions. 
     
     
         17 . The method according to  claim 10  wherein the distances measured between the radar sensor unit and the at least two ground positions are averaged by the control unit or the radar sensor unit.