Challenges
Our linear actuator had to fit within medical environments and other special environments, so being able to control the components used inside and also the grease was essential. Another factor to consider is that the linear actuator had to lift weights not generally found on office desks (medical monitors can reach 60 lbs, and their other devices can be just as heavy, such as microscopes). Additionally, some of the workstations sold to clients can tilt, which would put a side load on the linear actuators. The leg containing all the components is typically used in heavy lifting applications that would not tolerate the linear actuator tilting at all.
Solutions
The linear actuator column is designed with aluminum as the material because it would avoid corrosion in the typical environment the workstations are found in. However, material can change as per needed since the dimensions are controlled by the engineers. The grease that is used was chosen after extensive testing from the samples provided by vendors I worked with. The grease had a thicker consistency to stay on the linear actuator in its vertical orientation and was biologically safe to humans (and animals). The plastic spacers and profile of the extrusion was selected and tested to withstand the side loading application of the linear actuator, which also had to go along with the testing and selection of the motor and spindle.
In this project, I worked heavily with FEA, testing, and vendors/manufacturers for the different linear actuators. The project also required heavy testing, and testing standards had to be designed. Some external testing was done for more extreme environments, such as clean room environments.
