A clamp for gripping sheet metal and being able to be used in association with a manipulating arm, called a robot, and including: - a rigid frame capable to be connected to a support, such as a rigid foot or said robot, - a mobile subassembly, connected to said frame, and comprising: - a first so-called stationary arm, - a second so-called mobile arm, and - a main actuator capable of moving the mobile arm relative to the stationary arm according to a first degree of freedom, in translation or rotation, so as to close or open the clamp in order, respectively, to grip a sheet metal assembly between the stationary and mobile arms or to release the sheet metal assembly, and - a balancing module, introducing an additional degree of freedom between said support, on the one hand, and, on the other hand, an assembly integrating said mobile subassembly (3, 4, 8), so as to balance the forces exerted on the ends (2, 9) respectively of the stationary and mobile arms in a closed position, said balancing module comprising: - a device (22, 23, 24) enabling a movement according to said additional degree of freedom, in translation of said mobile subassembly (3, 4, 8) with respect to the support, - a balancing system (52, 58) including a flexible device (22, 25, 53) connected to said mobile subassembly (3, 4, 8) and urging, according to said additional degree of freedom, at least one member connected to said support, and at least one balancing actuator, capable of bringing said mobile subassembly (3, 4, 8) into a balancing position with respect to said support, characterized in that said balancing module is an electromechanical module, in which said member urged by said flexible device (22, 25, 53) is a nut of a screw-nut system of which the screw, which extends parallel to the direction of said translation movement, is driven in rotation by said balancing actuator, and in that said flexible device (22, 25, 53) includes two balancing springs that extend substantially parallel to the direction of said translation movement, and exert opposing actions on said nut. - a rigid frame capable to be connected to a support, such as a rigid foot or said robot, - a mobile subassembly, connected to said frame, and comprising: - a first so-called stationary arm, - a second so-called mobile arm, and - a main actuator capable of moving the mobile arm relative to the stationary arm according to a first degree of freedom, in translation or rotation, so as to close or open the clamp in order, respectively, to grip a sheet metal assembly between the stationary and mobile arms or to release the sheet metal assembly, and - a balancing module, introducing an additional degree of freedom between said support, on the one hand, and, on the other hand, an assembly integrating said mobile subassembly (3, 4, 8), so as to balance the forces exerted on the ends (2, 9) respectively of the stationary and mobile arms in a closed position, said balancing module comprising: - a device (22, 23, 24) enabling a movement according to said additional degree of freedom, in translation of said mobile subassembly (3, 4, 8) with respect to the support, - a balancing system (52, 58) including a flexible device (22, 25, 53) connected to said mobile subassembly (3, 4, 8) and urging, according to said additional degree of freedom, at least one member connected to said support, and at least one balancing actuator, capable of bringing said mobile subassembly (3, 4, 8) into a balancing position with respect to said support, characterized in that said balancing module is an electromechanical module, in which said member urged by said flexible device (22, 25, 53) is a nut of a screw-nut system of which the screw, which extends parallel to the direction of said translation movement, is driven in rotation by said balancing actuator, and in that said flexible device (22, 25, 53) includes two balancing springs that extend substantially parallel to the direction of said translation movement, and exert opposing actions on said nut. - a first so-called stationary arm, - a second so-called mobile arm, and - a main actuator capable of moving the mobile arm relative to the stationary arm according to a first degree of freedom, in translation or rotation, so as to close or open the clamp in order, respectively, to grip a sheet metal assembly between the stationary and mobile arms or to release the sheet metal assembly, and - a balancing module, introducing an additional degree of freedom between said support, on the one hand, and, on the other hand, an assembly integrating said mobile subassembly (3, 4, 8), so as to balance the forces exerted on the ends (2, 9) respectively of the stationary and mobile arms in a closed position, said balancing module comprising: - a device (22, 23, 24) enabling a movement according to said additional degree of freedom, in translation of said mobile subassembly (3, 4, 8) with respect to the support, - a balancing system (52, 58) including a flexible device (22, 25, 53) connected to said mobile subassembly (3, 4, 8) and urging, according to said additional degree of freedom, at least one member connected to said support, and at least one balancing actuator, capable of bringing said mobile subassembly (3, 4, 8) into a balancing position with respect to said support,