I could really use, and appreciate immensely, some measurements. This lever\fulcrum\articulation math is doing my head in! How long are the linkages from the motor pivot to the shoulder joint? What is the set back from the arm joint supports (the upright where the two pipes pivot) to the motor pivot centrepoint? How tall are the arm supports? What is the length of the throw on the motor arm (from the motor shaft centre to the triangle centre)? What's the angle between the two arm push rods? Any help is greatly appreciated.
I can try to provide you with some of this. From the motor to the shoulder joints - the length was 2 feet. but that was a random length - I picked it only to try to size out the body to the arms. As I said in the video - you can make the size exactly how large or small you want. The video I copied from his was probably about only 1 foot long linkage. Same thing with the uprights - whatever distance you want for the size you want it to be. The length does not change anything to the work of the motor. All the torque goes to lifting the arms and the head. That's what is most important. I probably make the arms a bit too long. I have since broken one of the 1" 45s PVC connectors from the torque of lifting. I replaced it and it hasn't broken again. The head is a bit too heavy - I had to double up bungy cords to help the motor with the lift. The length of the throw is a good question. I made it 2" and at first thought that wasn't going to be enough but it was. I learned the shafts aren't really moving that much but because of so much distance with the lift of the arms and head, it doesn't take a lot. Finally the arm push rods, I'm not sure if you are talking about from the motor? The three rods are exactly spaced at 1/3rds of the circle of the motor. The double PVC pipes for the arms I had to cut and adjust once I had everything connected to get the arms to open and close how I wanted. That's why I used smaller PVC pipe an d bolts to connect the arms, that let me adjust the length to work. That's all the info. I can give you. I do draw things out a bit as I build but I am nothing like the guy who's design I used. I'm more of an "adjust as you go" builder. Good luck
Here's where I bought them last on Amazon. But you can also get them on Ebay.. The main thing I found out - you need to make sure the device is covered - some have completely open electronics which can catch on things. But the main thing is to have the speed controller knob connected to a metal cover. The first ones I bought the knob was just connected and hanging loose. I broke one off almost immediately by catching it on something. Anyway here's the link - - - www.amazon.com/gp/product/B00DVGGWC0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Just look for a 12v DC motor speed controller. Good luck
Very cool. And love the idea of the 1 inch over 3/4 inch, to make it more easily storable!
Wow, can't wait to see it finished!!
I thought my Halloween video serious were cool, your stuff is great.
dope!
I could really use, and appreciate immensely, some measurements. This lever\fulcrum\articulation math is doing my head in!
How long are the linkages from the motor pivot to the shoulder joint?
What is the set back from the arm joint supports (the upright where the two pipes pivot) to the motor pivot centrepoint?
How tall are the arm supports?
What is the length of the throw on the motor arm (from the motor shaft centre to the triangle centre)?
What's the angle between the two arm push rods?
Any help is greatly appreciated.
I can try to provide you with some of this. From the motor to the shoulder joints - the length was 2 feet. but that was a random length - I picked it only to try to size out the body to the arms. As I said in the video - you can make the size exactly how large or small you want. The video I copied from his was probably about only 1 foot long linkage. Same thing with the uprights - whatever distance you want for the size you want it to be. The length does not change anything to the work of the motor. All the torque goes to lifting the arms and the head. That's what is most important. I probably make the arms a bit too long. I have since broken one of the 1" 45s PVC connectors from the torque of lifting. I replaced it and it hasn't broken again. The head is a bit too heavy - I had to double up bungy cords to help the motor with the lift. The length of the throw is a good question. I made it 2" and at first thought that wasn't going to be enough but it was. I learned the shafts aren't really moving that much but because of so much distance with the lift of the arms and head, it doesn't take a lot. Finally the arm push rods, I'm not sure if you are talking about from the motor? The three rods are exactly spaced at 1/3rds of the circle of the motor. The double PVC pipes for the arms I had to cut and adjust once I had everything connected to get the arms to open and close how I wanted. That's why I used smaller PVC pipe an d bolts to connect the arms, that let me adjust the length to work. That's all the info. I can give you. I do draw things out a bit as I build but I am nothing like the guy who's design I used. I'm more of an "adjust as you go" builder. Good luck
Can you send me the link to your motor speed controller?
Here's where I bought them last on Amazon. But you can also get them on Ebay.. The main thing I found out - you need to make sure the device is covered - some have completely open electronics which can catch on things. But the main thing is to have the speed controller knob connected to a metal cover. The first ones I bought the knob was just connected and hanging loose. I broke one off almost immediately by catching it on something. Anyway here's the link - - - www.amazon.com/gp/product/B00DVGGWC0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Just look for a 12v DC motor speed controller. Good luck
Great job