FIELD: measurement equipment.SUBSTANCE: invention relates to devices for body motion definition. The device comprises a facility to determine acceleration and a computer to calculate body motion based on acceleration data, a section of engagement/disengagement for fixation of the working part on the main block of the device or disconnection from it, besides, the computer is made as capable of performing a procedure to define engagement/disengagement on the basis of acceleration change, when fixing the fixed working part on the section of engagement/disengagement or when disconnecting from it, and performance of body motion calculation on the basis of the defined engagement/disengagement, when switching to the mode corresponding tot he condition after engagement/disengagement. In the second version of device realisation there is additionally a memory device to store data and a display device to display calculation result, and also many sections of engagement/disengagement depending on the type of the fixed working part, besides, the computer is also made as capable of defining the type of the fixed working part on the basis of acceleration change and performance of body motion calculation on the basis of the defined engagement/disengagement and type, when switching into the mode corresponding to the type of the fixed engaged working part. In the third version the section of engagement/disengagement comprises a guide for moving or rotating the engaged working part, when the fixed working part is fixed on the main block of the device or disengaged from it, and an impact section, with which one part of the fixed working part collides when engaging and disengaging the fixed working part along the guide. In the fourth version the device has a body for holding the facility to define acceleration and the computer, at the same time the body comprises an impact working part, subject to impact during collision, and the computer is configured capable of defining acceleration da
