Magnetic nanoparticles possess immense potential for various applications, including colloidal nanorobots, drug delivery, cancer treatment via hyperthermia, and tunable materials. However, colloidal nanorobots with independent locomotion and multi-actuating capabilities controlled by electromagnetic fields remain a challenge. Our approach for fabricating nanorobots implements the dipolar interaction between anisotropic particles with different shapes and materials to create tunable configurations between particles. However, the dipolar interaction force and torque of ellipsoidal particles depend on their relative positions and orientations. We quantify the dipolar interactions by implementing the ellipsoid-dipole model with unit quaternions to capture the high-dimensional interactions between ellipsoidal particles in modeling magnetic nanorobots. We report the analytical expressions for the interaction of dipolar forces and torques between magnetic ellipsoids with different shapes and material properties. The analytical expressions capture the established behavior of uniform magnetic spheres. Additionally, we report Brownian dynamics simulations of interacting magnetic ellipsoids under a time-varying magnetic field. We show simulation results for binary suspensions composed of ellipsoids with different shapes, aspect ratios, and material properties. We characterize the probability between particles in particle space and relaxation time under different dipole-field and dipole-dipole interaction strengths. The simulation results match the behavior of dilute suspensions composed of monodisperse ellipsoids with different aspect ratios. Additionally, the simulation results show a variety of synchronous and asynchronous rotation dynamics between particles for different dipolar interaction strengths.
