A mobility aid.It includes: a track group,It includes a gear rail.One side of the gear rail is provided with one tooth row of the complex tooth shape；One seat,It is slidably arranged on the gear rail；The base comprises a pulley block and a brake block.The pulley block slides relative to the track block,The brake group comprises a roller and is engaged with the gear row.And a brake piece is in a free state after being engaged, clamped and separated with respect to the displacement of the roller；And a holding group,Its movable assembly is arranged on the base and connected with the brake piece.The gripping group includes an armrest extending outwards toward one side of the track group.Users only need to grasp the grip group by hand, and then use the grip group to move the brake parts to separate the roller, while the action aids can reach the rehabilitation needs by moving the roller relative to the tooth rail.一種行動輔具，其包括：一軌道組，其包括有一齒軌，該齒軌一側具有複數齒形之一齒排；一機座，其滑設於該齒軌；該機座包括有一滑輪組以及一制動組，該滑輪組相對滑動於該軌道組，該制動組包括有一滾輪並相對該齒排嚙合，以及一制動件相對該滾輪位移而相互嚙合卡抵及分離後呈自由狀態；及一握持組，其可動組配於該機座並連動該制動件，該握持組包括有一扶手朝該軌道組的一側向外延伸。使用者只須手抓握持組，進而以握持組連動制動件分離滾輪，而行動輔具則能藉由滾輪相對齒軌行走達到復健需求。
