Parallel-field electrorheological clutch: Enhanced high shear rate performance

We present an electrorheological (ER) fluid cylindrical clutch which achieves stable shear stress at high shear rate, and demonstrates superior performance compared with the traditional ER clutches. The design is realized by employing alternate-stripe electrodes on the inner cylinder, with either dielectric or metallic outer rotor. The alternate stripe electrodes generate electric fields with a component parallel to the shearing direction, so that ER particles can form chain structures parallel to shear and thereby bring significant enhanced device performance at a high shear rate. Differences due to the use of dielectric or metallic outer rotor are shown to be compatible with expectations based on simulated electric-field patterns.