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In this paper, we discuss requirements formulation for CubeSat on-board sensors characteristics for solving identification problem. The problem is to estimate design and inertial parameters of CubeSat-format nanosatellite using on-board sensor measurements. Identification problem for CubeSats becomes more and more actual every year because CubeSat design becomes more complicated due to complex missions requirements. Modern CubeSats can be equipped with deployable solar panels, propulsion units and different types of transformable structures. This fact makes it necessary to study CubeSats as bodies with variable inertial and design characteristics. In this article the design parameter is fuel level in the CubeSat propulsion system and inertial parameters are inertial coefficients (inertia moments analog). We study requirements formulation for magnetometer and angular rate sensor, as this combination of sensors is the most popular in CubeSat development. The main idea of this paper is to study the sensitivity of measurements to estimated parameters. This sensitivity depends on time and measurement noise, large sensitivity leads to low estimation error. We conducted a numerical study and provide an algorithm which allows to define sensitivity-time-noise dependence for each type of sensors and formulate the requirements for their characteristics.

As it is impossible to set high accuracy of the initial data for theoretical calculations of the design parameters, such as the mass-centering and inertial characteristics of nanosatellites, the problem of experimental determination of their actual values arises. For a number of reasons, the devices designed for large spacecraft are not appropriate for the small ones. This paper describes a device developed at Samara University for measuring the center of mass coordinates and moments of inertia specifically for CubeSat nanosatellites, as well as a technology for experimental evaluation of the design parameters of nanoclass spacecraft. The accuracy of determining the design parameters using the proposed device is confirmed by a series of experiments with standards.

Due to inability to set a high accuracy of initial data in theoretical calculations of mass-centering and inertial characteristics of nanosatellites, a problem arises concerning the experimental determination of their actual values. For a number of reasons, the devices designed for large spacecraft are not appropriate for small ones. This paper describes a device for measuring the center of mass coordinates and moments of inertia developed at Samara University specifically for CubeSat nanosatellites, as well as a technology for experimental determination of the design parameters of nanoclass spacecraft. The accuracy of determining the design parameters using the proposed device is confirmed by a series of experiments with standards. Key words: nanosatellite, center of mass coordinates, moment of inertia, inertia tensor, measuring platform.