On the inner wall of the tunnel are electrical connections which are connected and disconnected manually. The walls also have electrical connections for the control and monitoring of the docking mechanism. These are disconnected manually before disassembly of the docking mechanism. The joint is sealed by two full seals made of silicon resin. Control and monitoring (Figure 1.24) reflect the specifications of the construction of these systems on the Apollo as a whole considering the features of the flight program. The system contains two fully analogous and independent electrical circuits supplied by autonomous sources of direct current at a voltage of 27 V. All of the switches are equipped with current shields, and some circuits are equipped with additional fusible protective devices. The docking mechanism contains eight pairs of microswitches for signaling and control (turning on the electromagnets to release the latches of the head and to turn off the electromagnets at a certain course of the rod during undocking). In “vitally important” circuits, additional redundancy is used (parallel and series actuation of the microswitches). Thus, all the control operations and associated signaling can be done from either of the two systems. Each of them may include two pyrotechnic needles to puncture the tanks of the pneumatic drive, that is, each can perform two couplings of the docking mechanism. There is an additional opportunity to supply voltage to the pyrotechnic needles using an electric cable attached manually to any source of voltage and to docking mechanism connectors. The supply of voltage to the pyrotechnic fuse, which is supplied from an independent bus for pyrotechnics, can be done remotely or automatically. To measure temperature the docking mechanism has a sensor and indicator on the astronaut's control panel. The docking device of the Apollo was used to dock the command module in the lunar program, in the Skylab programs, and in the Apollo-Soyuz project. Despite a.number of deviations in operation all dockings were made successfully.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==