The term dynamometer refers to an instrument used to measure a force. It can also refer to a testing machine capable of applying forces with a given accuracy. Only the first of these meanings is referred to in this text.

A dynamometer is composed of a transducer or load cell comprising a steel proof body which receives the force to be measured and deforms elastically by the application of this force. In modern transducers, such deformation (strain) is communicated to a miniature electric circuit attached to the proof body, resulting in the modification of the electrical resistance. This resistance variation is measured by the Wheatstone bridge method, whereby two legs of the electric circuit are supplied with an analogue voltage, continuous or intermittent. An analogue variable voltage depending on the force applied to the dynamometer is collected between the two other legs in the circuit.

‘Force magnitude’ is, from the mechanical theory point of view, a vector input which must be taken into account by the precision measures, as well as other mechanical laws, such as action and reaction principles, action at a distance, etc. This approach leads to the adoption of a certain number of precautions, both in the design and use of a dynamometer.

Learn more about: the dynamometer; force measurement

NOTE : Spanish version /en/tecnologia/sensores-de-fuerza/dinamometro-definicion