may also be large , which is 60% of . When the momentum is equal to the motion the approach of the bodies ceases; from this equality one can find the critical value of the recovery coefficient at which linkage without the action of the jet control system does not occur. For the APDA, for example, . Consequently, it is expedient to supplement the minimum coefficient of recovery s; in impacts with roll these shock absorbers are substantially deformed. Due to damping in the Soyuz APDA . The relative velocity of the spacecraft in roll after linkage may also be substantial (for the APDAs the maximum value of its velocity . 5.6.5. Shock Absorption After Linkage The general case of impact immediately after linkage, in which the longitudinal, transverse, and angular shock absorbers all operate at once, is analogous to the case examined in section 5.5.3 for the “rod and cone” docking device. However, there are a number of features, the main ones being: 1) the possibility of substantial angular roll velocities; 2) large inertia of moving parts of the docking mechanism; 3) the form of characteristics of the longitudinal shock absorber; 4) the specific requirements on the characteristics of angular shock absorbers. Just as in the “rod and cone” docking devices, the operation of the linear and angular shock absorbers may be studied independently. In the rating of the linear shock absorbers it is important for electromechanical docking mechanisms to have a central impact. Practice has shown that the inertia of moving parts accelerated on impact (six nuts of the ball-screw converters, elements of transmission and differentials) in the developed peripheral type docking mechanism is large, and may not be substantially reduced. Moreover, they do not have the initial “soft” stage of the longitudinal shock absorber. These two circumstances lead to a significant increase in additional inertial loads on the longitudinal shock absorber on central impact. They dynamic component may increase the force on impact by more than a factor of 2 (Figure 5.24).
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