An Ice Track Equipped with Optical Sensors for Determining the Influence of Experimental Conditions on the Sliding Velocity

Abstract

The ability to slide on ice has previously focused on the measurement of friction coefficient rather than the actual sliding velocity that is affected by it. The performance can only be directly measured by the sliding velocity, and therefore the objective was to design and setup a facility to measure velocity, and determine how experimental conditions affect it. Optical sensors were placed on an angled ice track to provide sliding velocity measurements along three sections and the velocity for the total sliding distance. Experimental conditions included the surface roughness, ambient temperature and load. The effect of roughness was best reported with a Criterion of Contact that showed a similar sliding velocity for metal blocks abraded with sand paper smoother than 600 grit. Searching for the effect of temperature, the highest sliding velocity coincided with the previously reported lowest coefficient of ice friction. Load showed the greatest velocity increase at temperatures closer to the ice melting point suggesting that in such conditions metal block overcame friction forces more easily than in solid friction. Further research needs to be conducted on a longer ice track, with larger metal surfaces, heavier loads and higher velocities to determine how laboratory experiments can predict real-life situations.

The Influence of Isotropic Surface Roughness of Steel Sliders on Ice Friction Under Different Testing Conditions

“…At the same time, the influence of roughness on velocity was somewhat less pronounced at lower ice and ambient temperatures, especially the samples with higher roughness (samples SP30 and SP150) showed a less pronounced decrease in velocity. It is worth mentioning that also in the previous research of the authors, the influence of surface texture of the sliders on their velocity typically decreased at lower ice and ambient temperatures which was true for tests on the inclined ice track tribometer [12] as well as for skeleton field tests [11]. Similar observations were made independently by the winter sports athletes who collaborated in the skeleton field tests.…”

“…an angle of 16°, which is slightly above the minimum to initiate the sliding motion of the test samples and is at the same time sufficient to prevent from adhesive sticking of the samples in the starting position. More information on the working principle of the inclined ice track tribometer can be found in Reference [12]; however it should be noted that the latest device updates include a stronger frame, improved optical sensors and an additional climate chamber surrounding the device for minimization of the changes in temperature and humidity which occur due to the heat emitted by the researcher/operator who is present inside the climate simulation chamber during the experiments. Before the tests, the ice surface was levelled with a specially designed planner, which can move linearly along the ice track over rolling bearings.…”

A Holistic Approach Towards Surface Topography Analyses for Ice Tribology Applications

“…In some studies, only 2D profile data are used (Kietzig et al, 2010a;Sukhorukov and Marchenko, 2014;Scherge et al, 2018), but in most of the research 3D surface measurements or combination of both are considered (Bäurle et al, 2007;Rohm et al, 2015;Jansons et al, 2016;Spagni et al, 2016;Lungevics et al, 2018;Scherge et al, 2018;Ripamonti et al, 2020;Liefferink et al, 2021). The problem with 2D profile measurements is that 2D profiles often provide misleading information about the surface texture, especially when anisotropic surfaces are used.…”

The Influence of Ice Texture on Sliding Over Ice

“…This plane angle has been chosen to ensure sliding a stationary position, and provide a long enough sliding time to detect differences on various ice textures. Sliding speed has been measured using four retroreflective sensors arranged along the length of the track [7]. b.…”

“…In order to perform such experiments, two devices based on the inclined plane principle have been used at the laboratory. Both of these devices have previously been tested and proven to be reliable and useful for such tests [7]. Results are analysed taking into account the contact area between ice and sliding object; the contact area has been measured with a simple test method that shows the top surface.…”