Traditionally, inertial navigation system has been an expensive technology, which limited its application to high-end military vehicles, precision-guided missiles, or aircraft. Since the advent of MEMS technology and low-cost gyroscopes and accelerometers, inertial navigation is now being deployed even in cost-sensitive & low-powered applications such as for soldier and personnel navigation.
One might wonder why inertial navigation is required for soldiers, emergency responders, or other persons when one can make do with GPS navigation. It is important to understand that though GPS navigation is now easily available at a very nominal price, it is not advisable to solely rely on it.
Following Are Some Short comings Of The INS-GPS-Based Personnel Navigation Systems:
Poor or No Indoor Coverage: GPS signals can be extremely poor in strength in the indoor environment. As a result, tracking soldiers, firefighters, or other emergency responders when they are inside becomes difficult. The signals are even poorer in multi-storeyed structures or underground bunkers.
The Possibility Of Spoofing/Jamming: Location data of soldiers or undercover personnel could be extremely critical to the success or failure of military actions. GPS signals are prone to spoofing (resulting in incorrect information) and jamming (resulting in information loss), which can jeopardize the critical missions and may even lead to a destruction of human assets.
INS-GPS Systems For personnel Navigation
Aeron’s Castor MEMS-INS (under development) is an extremely low powered, micro- form factor position sensor that runs proprietary machine-learning algorithms, fusing data from accelerometers, gyros, and GNSS to lend real-time location of personnel and vehicles.
Castor’s adaptive filtering algorithm detects zero velocity, performs real-time calibration of a soldier’s step size, and tracks the last known position to generate seamless navigation data even in an indoor environment. Figures demonstrate the motion sensor plots when the user is walking, motion rate analysis, and step count increasing with time.
