The chair includes a base member, a support member, at least a linkage member configured on the base member and to a bottom side of the support member in a movable manner, at least a first power assembly connected between the support member and the linkage member, and a second power assembly connected between the linkage member and the base member. The first power assembly provides an angle variation between the support member and the linkage member, whereas the second power assembly provides a separate angle variation between the linkage member and the base member. The chair provides both stand-up assistance and comfortable reclining, and has fewer components, less cost, more flexible and smooth linkage, and requires less power to operate.
