An evaluation subject formed by a cut sample of a conveyor belt is mounted on a flat substrate with an inner periphery-side cover rubber layer located on the upper side, a support roller mounted in a frame is horizontally pulled and rolled in the longitudinal direction of the evaluation subject by pulling the frame by a wire while the support roller is pressed vertically downward against the upper surface of the evaluation subject at a preset pressure using a pneumatic cylinder without substantial deformation of the outer peripheral surface thereof, and tensile force in a horizontal direction measured at this time by a tensile force sensor connected to the wire is evaluated as resistance to moving over the support roller.

A method for processing friction data for vehicle tires on road segments, implemented by a processing system including at least one computer and an interface for remote communication with a plurality of vehicles, the method including: acquiring, from the plurality of vehicles, friction data for tires of the vehicles on a plurality of road segments, each friction datum including at least: a maximum coefficient of friction available to the vehicle on the road segment, and information relating to the road segment; establishing, for each road segment, a distribution of the friction data obtained from the plurality of vehicles for the road segment; and determining a plurality of road types, each road type comprising a set of road segments, from a measurement of similarity between the distributions of friction data obtained for each road segment.

A method for processing friction data for vehicle tires on road segments, implemented by a processing system including at least one computer and an interface for remote communication with a plurality of vehicles, the method including: acquiring, from the plurality of vehicles, friction data for tires of the vehicles on a plurality of road segments, each friction datum including at least: a maximum coefficient of friction available to the vehicle on the road segment, and information relating to the road segment; establishing, for each road segment, a distribution of the friction data obtained from the plurality of vehicles for the road segment; and determining a plurality of road types, each road type comprising a set of road segments, from a measurement of similarity between the distributions of friction data obtained for each road segment.

A device measures a frictional force and a film thickness of a lubricating oil film in different surface velocity directions. The device includes an experiment bench. A translation stage is mounted to the experiment bench, and is linearly movable. A main shaft system is mounted to the experiment bench. A glass disc is mounted to the main shaft system and is rotatable. An arcuate guide rail is disposed on the translation stage. A rotary base is mounted to the arcuate guide rail and is movable along the arcuate guide rail. A loading system is mounted to the rotary base. A steel ball of the loading system and the glass disc are movable relative to each other. A rotary bearing in the rotary base is configured to convert a frictional force generated from the relative movement to a pressure allowed to be collected by a pressure sensor on the rotary base.

A device measures a frictional force and a film thickness of a lubricating oil film in different surface velocity directions. The device includes an experiment bench. A translation stage is mounted to the experiment bench, and is linearly movable. A main shaft system is mounted to the experiment bench. A glass disc is mounted to the main shaft system and is rotatable. An arcuate guide rail is disposed on the translation stage. A rotary base is mounted to the arcuate guide rail and is movable along the arcuate guide rail. A loading system is mounted to the rotary base. A steel ball of the loading system and the glass disc are movable relative to each other. A rotary bearing in the rotary base is configured to convert a frictional force generated from the relative movement to a pressure allowed to be collected by a pressure sensor on the rotary base.

The invention disclosed a friction coefficient measuring device under the condition of material periodic deformation. The measuring device is mainly composed of a torque sensor, a sleeve system, an upper sample, a lower sample, a flexible fixture, an air bearing, a clamping system, a tension-compression sensor, a support rod, and a support table. A working module of a friction-wear testing machine is connected with the torque sensor and then connected with the sleeve system to fix the upper sample. A rotating module of the friction-wear testing machine is used for connecting the flexible fixture to fix the lower sample. The tension-compression sensor can accurately measure the radial force between the upper sample and the lower sample. The torque sensor can measure the load torque values of the upper sample and lower sample during testing. According to the curve of the load torque value and radial load value change between the upper sample and lower sample, the friction coefficient between the flexible bearing and flexible gear is obtained.

The invention disclosed a friction coefficient measuring device under the condition of material periodic deformation. The measuring device is mainly composed of a torque sensor, a sleeve system, an upper sample, a lower sample, a flexible fixture, an air bearing, a clamping system, a tension-compression sensor, a support rod, and a support table. A working module of a friction-wear testing machine is connected with the torque sensor and then connected with the sleeve system to fix the upper sample. A rotating module of the friction-wear testing machine is used for connecting the flexible fixture to fix the lower sample. The tension-compression sensor can accurately measure the radial force between the upper sample and the lower sample. The torque sensor can measure the load torque values of the upper sample and lower sample during testing. According to the curve of the load torque value and radial load value change between the upper sample and lower sample, the friction coefficient between the flexible bearing and flexible gear is obtained.

A method and system for estimating the potential friction between a tire and a rolling surface in which: a first and second engaged-friction/kinematic-quantity reference curve respectively corresponding to a first and to a second reference value μρ.sub.1, μ.sub.P2 of potential friction with μ.sub.P2>μ.sub.P1 are provided; a first and a second kinematic quantity threshold value or a first and a second engaged friction threshold value are provided; the engaged friction μ between the tire and the rolling surface is determined; a current value of a kinematic quantity between the tire and the rolling surface is determined; a current working point given by the engaged friction μ and the current value of the kinematic quantity is determined; and the current value of the kinematic quantity is compared with the first and the second kinematic quantity threshold value or, respectively, the engaged friction μ is compared with the first and the second engaged friction threshold value.

A method and system for estimating the potential friction between a tire and a rolling surface in which: a first and second engaged-friction/kinematic-quantity reference curve respectively corresponding to a first and to a second reference value μρ.sub.1, μ.sub.P2 of potential friction with μ.sub.P2>μ.sub.P1 are provided; a first and a second kinematic quantity threshold value or a first and a second engaged friction threshold value are provided; the engaged friction μ between the tire and the rolling surface is determined; a current value of a kinematic quantity between the tire and the rolling surface is determined; a current working point given by the engaged friction μ and the current value of the kinematic quantity is determined; and the current value of the kinematic quantity is compared with the first and the second kinematic quantity threshold value or, respectively, the engaged friction μ is compared with the first and the second engaged friction threshold value.

A method and apparatus for testing rings cut from pipes for use in making subsea pipelines are described. The method for determining the whether a test ring is correctly assembled in a test chamber for testing pipes for use in making subsea pipelines comprises: mounting a test ring in a pressure chamber such that the ends of the test ring forms seals with opposing surfaces of the chamber to isolate the inside of the test ring from the outside; providing means for measuring the displacement of the test ring; providing means for measuring a force applied to the inner surface of the test ring; applying a force to the inner surface of the test ring; and using the displacement measurement and force measurements to determine whether the test ring is correctly mounted in the pressure chamber.