I'm a complete newcomer to Arduino, however my main goal is to build a robotic arm as a starter project for robotics. Its task is to lift light-weight objects, such as a small cup of water. The arm will consist of 3 sections that will support a tongs-like construct at the end, and the whole arm is planned to be situated on a rotating platform. As no other material is available, I chose to build it out of wood(one of the lighter types, like birch). My problem is that although I have a concept of the machine itself(sketches, some blueprints and a cardboard model as well), I have not really found servos in the online store that seem to be strong enough. On top of that, I noticed how everyone is talking about shields, and I am starting to suspect that they are a crucial part of simultaneous motor control. Guys, I simply can't abandon this project, and I am going to engineer it to the very end, and further. So, I would be grateful if some of you shared their ideas about the problem. Just some initial information, so that I can start it off.
(Currently, I have an Arduino starte pack and an Arduino Mega in my posession. I have all kinds of carpentry tools, as well as a soldering set, and I have free access to wood, and roughly 110 eurs of additional budget. I will gain more money over time, but the current budget sets my priorities.)
Shields are not needed to drive servos though they can sometimes be useful, particularly if you need to run lots of servos at once. If you post some of your drawings showing the number and placing of the servos together with approximate weights of the components and your payload that will make it easier to help.
But many people have already built robot arms with Arduinos and servos so Google also contains much useful information.
Kunyak:
Its task is to lift light-weight objects, such as a small cup of water.
I would not consider a small cup of water to be "light-weight".
With a robotic arm you need to think of torque rather than just weight. As the arm extends away from the base the torque caused on the base joint by a fixed weight in the gripper will increase.
Perhaps you should think of counter-balancing a significant part of the load.
It is also important to minimize the weight of the arms themselves and one way to do that is to mount all the servos in the base and arrange for them to control the extremities through levers.
If you post a diagram of the machine you are planning to build it will be easier to help. Please put dimensions on the diagram. See this Simple Image Guide
Its always a wise idea to make such a robot arm counterbalanced - greatly reduces the torque
requirements, reduces flex during movement as everything stays roughly balanced (other than the
load itself).
Hobby servos are not powerful, they are not designed to be, and overloading them will cook and destroy
them. However I guess everyone has to learn this the hard way at least once!
Once you get into mechanical contraptions it pays off to understand how to calculate forces and torques,
ie the branch of physics known as mechanics. Tip: use SI units.
I have not really found servos in the online store that seems to be strong enough.
The servo motors has limitated from the torques is, if you need more powerful servos, use up 10kN torques servos. In the industrial there is many servos uses for high torque.
It means there will not possible that if you looking for reference servos.
I spent some time to review my plans, to work out new ideas, and to improve the quality of my previous blueprints. The photos are taken from smartphone, but they are all HD, and i will upload some documentation files, just so you can make heads or tails of my badly made drawings(seriously, I have not figured that out yet). Let me hear your ideas, they will help get me further.
Please don't get mad at me because of the cardboard model. It is hideous, but maybe it will come in handy when I build the first working prototype.
It is hideous, but maybe it will come in handy when I build the first working prototype.
