Help Needed for Designing a Robotic Arm for High School Project

[MonsterBot]

Hello everyone,

I'm currently a senior in high school, and for our final year project, we've been tasked with designing and building our own robotic arm. This is a really exciting challenge, and we're using an Arduino board, some budget-friendly servomotors, and 3D-printed parts for the construction.

We've made some good progress so far. The base and the attachment point for the arm are complete, but now we're moving on to the design of the arm itself, and we're encountering some critical issues that we need help with.

Here are the main concerns we're facing:

Weight Handling Capacity of Servomotors: We are using MG995 servomotors for Servo 1 and Servo 2, while Servo 3 is a smaller blue servo (I don't have its exact model at the moment). Our big question is whether these servomotors can handle the weight they will be subjected to. Specifically, we need to know if these servomotors have enough torque to lift and move the arm without overheating or failing.

Need for Counterweights: To ensure smooth and stable movements of the robotic arm, we're wondering if it's necessary to add some form of counterweight. Would incorporating a counterweight help in balancing the arm and reducing the load on the servomotors? If so, what would be the best way to design and position these counterweights?

General Design Tips: Any additional tips or advice on the overall design of the robotic arm would be extremely helpful. We're particularly interested in suggestions for improving the efficiency, stability, and durability of the arm.

We would greatly appreciate any insights or guidance from those with experience in robotics and engineering. Your advice could really help us overcome these challenges and successfully complete our project.

Thank you so much in advance for your assistance!

 

[artbyrobot]

you could use 2 servos for motor 1 and 2 to double it and you could mount motor 2 servos off the arm on the base and use a cable/tendon based actuation method where fishing line goes from servo horn through tpfe tubing to the joint and this takes all weight off the arm and puts it on base so arm maxes out its load capacity. I would not use counter weights.