A submersible vehicle comprising a plurality of rigid submersible vessels 2, 3, some of which, 2, include propulsion means and some of which, 3, do not include propulsion means, the rigid submersible vessels being coupled by resilient couplings which are adapted to transmit pulling and braking forces between adjacent rigid submersible vessels. The method comprises: pouring a liquid metal onto the surface of a heterogeneous solid base metal coated with a soldering flux; rolling the liquid metal and the solid metal under pressure; solidifying the liquid metal and making it bond to the surface of the solid base metal under rapid cooling to realize metallurgical bonding of the two or more metals. Attachment components on the plunger and needle carrier engage such that withdrawal of the plunger releases the needle carrier for withdrawal into the syringe barrel. Each angled portion has a gentle slope and a steep slope that are asymmetrical sidewise. In order to enlarge the lifts of the damper, a multiplication gear is located between the damper and the movable area, more particularly in the form of a lever gear.