Actuator selection

I am looking for resources to calculate the load capacity (?) I will need for actuator selection.

I want to move a person, vertcally, up to 5 inches - so a range from 50kg up to 180kg weight-wise.

Taking 180kg as the limit (400lbs), with a physical structure incorporating 2 linear actuators, linked electronically, so they are always moving synchronously, with speed not really being an issue at all (ie slow is fine), should I stick with:

2 x 180kg, 5" actuators or can I divide the work being done between them, and have
2 x 90kg (= 180kg total), 5" actuators?

The movement is vertical, and the simplest (to my inexperienced mind) design would be to have 2 x vertically oriented actuators. Are there better designs or resources / examples for designing this?

I have googled, but knowing the terms to use would be helpful. "Actuators for newbies" seem to stick to mini actuators at hobby robotic level and then there's a leap to industrial applications.

Any website / book suggestions much appreciated.

Thanks

Huh. Since the upgrade my post does not appear. :-/(I theorised adding another post to the thread would change this - hence the reply to self. It worked too ;))

linked electronically, so they are always moving synchronously

Do the actuators have internal pots for position feedback?

Maybe.

Not sure if it was unclear in my post or thread title, but I am trying to get resources to work out / learn / determine how to select the correct actuators for a project.

In other words, I have an idea, involving actuators, but do not know which ones to choose, due to lack of experience.

Further to this point, because I do not know which ones to select, I have not selected or purchased any.

First order of business is: which load capacity to select.

aarondc:
Are there better designs or resources / examples for designing this?

This book:

...devotes a lot of time, attention and math on the subject (without going in so deep you think you need a higher mathematics degree).

When you get to the choosing stage, or just want a virtual browse 8), have a look at Firgelli.

I can't seem to quote posts, which is as annoying as f#ck, so

@cr0sh: thanks - exactly the sort of thing I am looking for
@JimboZA - yeah! I have been looking through their site and a few others. Seem to be the go-to guys, surprised I didn't find any books or references for reading / study, might look again.

I think the subject I want to look at is "mechatronics"? Can anyone confirm or correct this notion?

I think the subject I want to look at is "mechatronics"? Can anyone confirm or correct this notion?

Yep, that's it: combination of Mechanics and Electronics afaik