A magnetostrictive system in the context of autonomous vehicles typically refers to the use of magnetostrictive materials to convert mechanical vibrations or strain into electricity. Magnetostriction is a property of certain materials that causes them to change their shape or dimensions in response to an applied magnetic field. Conversely, when mechanical stress or strain is applied to these materials, they can generate a magnetic field. This property forms the basis for magnetostrictive energy harvesting systems.
Here's a general overview of how such a system might work in an autonomous vehicle:
Selection of Magnetostrictive Material: The first step is to choose a suitable magnetostrictive material for the energy harvesting application. Terfenol-D, a compound of terbium, iron, and dysprosium, is a commonly used material due to its strong magnetostrictive properties.
Integration into the Vehicle Structure: The magnetostrictive material is integrated into parts of the vehicle structure that are exposed to mechanical vibrations or strain. These vibrations can arise from sources such as road irregularities, engine vibrations, or even the motion of the vehicle itself.
Transduction of Mechanical Strain to Magnetic Field: When the vehicle experiences mechanical vibrations, the magnetostrictive material within the structure undergoes a change in shape or dimensions. This mechanical strain causes the material to generate a magnetic field due to the magnetostrictive effect.
Magnetic Field Induction: The generated magnetic field interacts with coils of wire or other magnetic components placed near the magnetostrictive material. This interaction induces an electric current within the coils through electromagnetic induction, based on Faraday's law of electromagnetic induction.
Energy Harvesting Circuit: The induced electric current is then directed through a rectification and conditioning circuit. This circuit converts the alternating current (AC) generated by the mechanical vibrations into direct current (DC) electricity, suitable for charging batteries or powering electronic components in the autonomous vehicle.
Storage or Use of Harvested Energy: The harvested electricity can be stored in the vehicle's battery system for later use or directly used to power low-power components within the vehicle, such as sensors, communication devices, or auxiliary systems.
It's important to note that magnetostrictive energy harvesting systems are most effective when the vehicle is subject to consistent and relatively high levels of mechanical vibrations or strain. The efficiency of the system will depend on various factors including the choice of magnetostrictive material, the design of the transduction components, and the overall integration within the vehicle structure.
As of my last knowledge update in September 2021, magnetostrictive energy harvesting systems were being explored in various applications, including autonomous vehicles, to harness ambient mechanical energy and contribute to the overall energy efficiency of the system. However, specific developments and implementations beyond that time are not covered in my current knowledge.