Measuring motion & force with force sensors & load cells

Engineers need to know the range of motion and force involved in mechanical designs before mechanical designs become viable pieces of equipment that provide operational and worker safety.

It is important to consider that force generally indicates push or pull motion. The push or pull motion can be magnetic, gravitational or electrical in nature. Force is measured by a meter. Note that force is measured in pounds. For instance, a lion’s bite is measured as 1235 pounds of bite force.

A force meter measures tension and compression such as the force compression of the lion’s bite. When tension and compression are measured, it acts on a sensor and is commonly referred to as a transducer.

 

The chief load cell principle is that the strain gauge converts the load bearing into electrical signals. Thus, these electrical signals are converted to digital read outs useful to determine mechanical force. However, it is also important to know that there are different types of load cells useful for different purposes. These include:
. Pneumatic load cells
. Hydraulic load cells
. Magnetostrictive load cells
. Piezorestive load cells
. Inductive and reluctance load cells
. Strain gauge load cells

The Relationship between Force Sensors and Load Cells to Measure Motion and Force
Fundamentally, the job of force sensors and load cells are interrelated. This is due to the fact that force sensors and load cells read and record weight of objects and their range of motion. In the example of a processing plant, there is the need for determining weight and precision mechanical force on processing operations.

In most cases, if the processing operation relies on a robotic application where the product processed requires compression, it is necessary to know the weight of the force on the robotic equipment during the course of the operational function.

 

As its name indicates a force sensor measures force on parts and equipment. It can be stand and lever operated or a hand held digital device that measures movement (travel) and weight of force in pounds.A load cell measures force as it is in motion by determining the effect of the weight of force on a body or structure and is then converted into SI units. For instance, industrial plants where hoppers contain liquid or dry materials, this requires measurement using a load cell device as a transducer.

When force is applied, load cells receive an electrical signal that measures the weight of the force and the signal changes the read out in proportion to the signal received.

When motion and force is applied to aeronautical, industrial and medical parts, devices and equipment, today’s precision digital force sensors and load cells provide the detailed range of motion as well as the effect of force to ensure scales, hoppers, tanks, engines and conveyors are properly calibrated to meet manufacturers’ safety and efficiency ratings. Users of force sensors and load cells should have an understanding of engineered equipment load bearing and design.