I’m looking to start purchasing parts to complete some animatronic wings for a cosplay but was hoping to get some advice on the proper motors and electronics to purchase. I’d be purchasing four Actobotic Linear Actuators (was also considering Actuonix Light Duty Actuators as well) for spreading open and closing the wings. I’ll also be getting two Power Window Motors for flapping of the wings.
The Actobotic Linear Actuators showcase a GoBilda 5202 series motor but I’m unsure of whether I would need such a powerful planetary gear motor over a spur gear motor for almost half the cost? What kind of motor controller should I consider if cost efficiency is a concern? I’m also not sure of what kind of batteries to get? Would I be able to power the linear actuators and power window motors off the same batteries/motor controllers?
@socalfusions Welcome to the RobotShop Community! You’re far from the first person to reach out here about a wing build, with effectively that same question. Actobotics / GoBilda linear actuators are one of the only systems which are modular, but in your case, you can likely get away with purpose-built DC linear actuators: https://www.robotshop.com/en/standard-actuators.html https://www.robotshop.com/en/tubular-actuators.html
The choice of which depends on the weight of the wings and their dimensions.
If you’re using steel bars and intend to add a lot of weight, the actuators will need to be pretty beefy. If you’ll use carbon fiber tubes, ball bearings and keep the weight down as much as possible, the actuators don’t need to be powerful. it’s always best to purchase something which can provide more torque than you need rather than buying something only to find out it’s insufficient and have to spend even more.
Regarding batteries, for a lightweight built operating at 12V, you can use 3S LiPo. (Napkin math) Add up the total max current rating of all motors and that will need to be the battery’s maximum discharge rating. The capacity will determine how long the system lasts between charges, but you should consider at least 4Ah.
Thank you for your response, I would be starting with aluminum tubing at first to keep weight down while still being affordable and would definitely love the modularity from the actobotics/gobilda line. What would you say is the most popular yet affordable motor choices for this project? I’m still not sure if I could get away with using spur gear motors over planetary motors for cost savings. That clears up the battery confusion nicely, much appreciated!
Unfolding the wing is different if you stand upright and expect the motors to lift the weight of the wing, or you go into a ‘starting position’ and the wing unfolds horizontally.
Nevertheless, you can add pull-springs to the joints or even gas-dampers that helps to unfold.
It is possible to make the whole wing ‘weightless’ for the motors.
Check out those desktop lamps, how they keep the balance.
For budget, if you keep everything lightweight, you can get away with a single linear actuator and perhaps a pair of spur gears connected to one DC gear motor. No specific product to suggest since the overall weight is still unknown.
Yeah that’s a good point, some builds I’ve seen use gas dampeners to help raise the wings. How would you go about making the wing weightless for the motors? Desk lamps are actually a impressive usage of springs in a everyday item that is often overlooked, definitely could see it being used to help a wing build.
That would definitely keep the cost down, one thing I forgot to ask was what would be a good budget motor controller for actobotic linear actuators? Some of them vary wildly in price and I’m not sure how many actuators can run off of each board?
Note that the Actobotics product linked to in your first message indicates that the motor is not included. You’ll need to select a motor, then a method as to how you want to control it, the find a motor controller. The following article should help:
Check out the lower spring-bracket at the foot of the lamp. The fixpoint of the spring has an offset to the joint. Find a way to add that to your wing, then vary the length of the spring until it’s support is just right.
Another source to ‘borrow’ some ideas is the mechanism of a pocket umbrella. A single spring opens up the umbrella. A pocket umbrella usually has two joints, exactly how a wing would be.
Thanks for the article and pointing that out, I indeed was planning on getting four motors for the four actuators which is why I’m so concerned about the price as it seems to be quite a bit more with four motors, batteries, and motor controllers.
