Kinematics of a flush-mounted retractable door handle

Example for the design of a mechanism for a flush-mounted retractable door handle with separate kinematic syntheses for the two partial systems (two syntheses “in series”).

Bild bestehend aus Bestandteilen der Benutzeroberfläche von der ASOM v10 Kinematik-Software zum Fallbeispiel ""

Forces and torques are considered here in various alternative cases simultaneously, also taking into account further restrictions such as mounting conditions and collision conditions.

The two partial systems consist of a four-bar system, to which a slider-crank system is attached. The door handle first moves into a desired intermediary kinematic position and later into the desired ending position. The desired initial, intermediate and ending positions are retained even when the positions of bearings or joints are modified. This is guaranteed by the two activated two-plane syntheses. Altogether, eight cases are considered simultaneously: two possible drives, in each case with and without tension spring, and in each case with and without breakout force (2 x 2 x 2 = 8 cases). Every modification, like e.g. moving a bearing, always immediately causes an update of all results for all eight cases.