How to Calculate Force to find the right Actuator for your Application

What force actuator should I buy? We get asked this question at least a few times a day.

In today’s article, we will walk you through the process of calculating the force required by an electric linear actuator to lift the load in your application. There are a couple of factors involved when it comes to finding the right force, like the load, the angle at which it is being pushed, and the size of the load.

If you are pushing/pulling a load straight up, then the actuator you are looking to buy should be the same force rating as your weight. I would recommend using a bit of a cushion and going with a higher rated actuator than your load, just to be on the safe side. For example, in Fig.1, if your load is 50 lbs then the force rating (F) of the actuator should be greater than or equal to 50lbf.

Fig. 1

When the load and the actuator need to be mounted at an angle, the whole scenario changes by quite a lot. Since the actuator will be pushing at an angle, it would most likely be needing more force than the actual load to lift it.

 Fig. 2

In the above figure, if your load is 50 lbs and you need to calculate what force actuator you require if you mount it at 45° angle (θ) to the ground then you need to make sure that the force perpendicular to the load (F sin θ, in this case) is greater than or equal to 50 lbs.

This means that if you are pushing a load of 50 lbs at a 45° angle, you would need an actuator that can at least push 71 lbs.

Alternatively, if you are planning to push the load sideways and would like to push it at an angle of 60°, you would be using the same equations, only in this case,

Fig. 3

And using the same method as before,

So, to sum up, in each case you would be using the equation that is perpendicular to the load to calculate the required force rating of the actuator. It is a simple step but can help save you a lot of time when selecting the right force actuator.

If you require further assistance on selecting the right electric linear actuator for your application, give us a call at 1-800-676-6123, or email us at sales@progressiveautomations.com.