From Department of Theoretical and Applied Mechanics
Jump to: navigation, search


Sticker AlpineReplay.png


The project was started in 2010 at the initiative of Anatoly Lokshin, CEO of AlpineReplay ltd. The project involves AlpineReplay ltd., HORIS ltd. and Department "Theoreticla Mechanics" SPbPU. The main objective of the project is to create a mobile application for the skiers and snowboarders, allowing to log their detailed stats: track, speed, a number of jumps, stunt parameters, air time, a number of calories spent and much more.

Over 200 000 people all over the world use AlpineReplay app.

Areas of research[edit]

Object of research

Employees and students of Department "Theoretical Mechanics" conduct research within "AlpineReplay" project in the following directions:

  • development of the jump detection algorithm based on the fuzzy logic (MATLAB and C++)
  • identification of a rotation angle in a jump
  • development of a gyroscope calibration algorithm


Download AlpineReplay application[edit]

You can download AlpineReplay application using the following liks:

Basic stunts of skiers and snowboarders[edit]

  • Spin

Spins, as a rule, are done a frontside or backside, a snowboarder rotates 180° degrees clockwise/counterclockwise depending on the nature of the obstacle. Terms "frontside" and "backside" are used to describe snowboarder's spinning direction. "Frontside" indicates that a snowboarder in the goofy stance rotates clockwise, and in the regular stance, counterclockwise. "Backside" clockwise rotation is typical for the regular stance and the counterclockwise rotation is typical for the goofy stance.

Term "Cab" (сaballerial) means any frontside snowboarder's spin without performing a stance (regardless a half-turns number).

Spins are "corked" when the axis of the spin allows for the snowboarder to be oriented sideways or upside-down in the air, typically without becoming completely inverted (though the head and shoulders should drop below the relative position of the board).

  • Flip

Flip is a rotation around the horizontal axis, i.e. over the head. There are front flip, back flip and Lincoln Loop (side flip for skiers).

It is also important not only to perform a trick, but also to do it technically correct. Performing stunts is just a part of a job: the technique also matters a lot. So, during the world competitions abilities to keep balance, smoothness of the stunt, and, importantly, a touchdown are rated. For example, a significant number of points is removed for a touch of hand on landing.

It should be noted that it's not always possible to tell the difference between the rotation types without watching a replay.

Videos of the most spectacular stunts[edit]

Site of the project[edit]

A social network for skiers and snowboarders



1. Lokshin A.M., Kuzkin V.A., Roberts-Thomson C.L. Use of gyro sensors for jump detection, U.S. Patent Application № 62/001 935, May 28, 2014.

2. Lokshin A.M., Kuzkin V.A. Systems and methods for identifying and characterizing athletic maneurs. US patent, Application № 13/932 899, 2013.

3. Lokshin A.M., Kuzkin V.A. Method and apparatus for determining sportsman jumps using fuzzy logic. U.S. Patent Application № 13/612 470, Dec. 09, 2012.

4. Lokshin A.M., Kuzkin V.A., Dvas N.G. Device and method of gyro sensor calibration. US patent, Application № 13/291 844, 2011.