抄録
Most of caster walkers don't have any brake mechanism. Some of them have hand grip type brake mechanisms but it is not easy for some of the users. For those users, it is desirable if there is a brake system which works only at a time of emergency like an occasion of falling down. Properties of homogeneous ER fluid is ideal because it doesn't show any shear force but it shows a large shear force when a high voltage is applied between a narrow gap but it requires a very small electric current. The caster walker equipped with the ER fluid brake was developed to increase safety of the users.
