So far, there have been few studies on self-balancing stretchers both at home and abroad, and generally focus on the rescue equipment and ambulances. For example, a PLA PLA hospital has developed a manual stretcher balancing truck with manpower to manually adjust the stretcher angle when going uphill and downhill. A medical university developed an ambulance balancing bed using electromechanical equipment such as stepper motors and ball screws. The existing self-balancing device has the advantages of heavy weight and complex structure, which is not conducive to the ambulance personnel carrying and arranging rapidly, and the security and stability needs to be improved. For this reason, a detachable and automatically balanced cot bed was studied, which can be used as a stretcher, infusion therapy bed and temporary operation bed, with the advantages of low cost, light weight, simple structure and convenient carrying. The cot is suitable for use in the field, corridors and other bumpy rescue sites.

The main task of the detachable self-balancing cot bed is to realize the smooth transportation of the sick and wounded in a special environment, to avoid over-tilting and to reduce the secondary injury to the wounded and sick. In order to achieve the above objectives, the stretcher bed should have the basic functions of carrying the patient, adjusting the angle, cushioning and damping, and quick assembly and disassembly. Mainly includes the outer fixed support stretcher, adjustable stretcher inside, connecting rod mechanism and bed legs.

Among them, the outer fixed support stretcher to the medial adjustable stretcher, linkages and bed legs together, is the basic "skeleton" cot bed. When the wounded lay on the medial adjustable stretcher, the medial adjustable stretcher serves as the patient. The linkage mechanism has the function of automatically adjusting the angle. The linkage mechanism includes the mover, and the mover moves under the control of the control system to drive the linkage mechanism to adjust the angle in real time. Fixed in the bed leg spring device, with damping buffer function. In addition, each part of the structure can be quickly assembled and disassembled.