Robot Arm to make Tea

Hello Gurus,

I am new to Arduino but have some understanding of programming. I am thinking to make a robot Arm to make tea. I have been doing research for last few days to check available projects online but need some help / advice on below.

1). Robot Arm - which robot arm should I buy? I am thinking either of DFRobot 6 Dof or ROT2U 6DOF from banggood based on below tutorials.

Second option is cheaper and as I am unsure if I will really succeed in what I want to achieve I want to spend less if possible.

Secondly, both tutorials have used different mechanisms to control servos :

1). PCA9685 16-channel PWM controller
2). 2 Channel Motor + 16 Channel Servo Expansion Board For UNO Smart Car Chassis Robot Arm Sale - Banggood Mobile

Can you suggest which one should I use?

My project in brief

1). Step 1 : Arm goes on top of kettle. Arm has a water pipe connected to it. It will add water in the kettle

  1. Step 2 : after 2 minutes, Arm will go and check template of the water. Repeat every 30 seconds until desired temp is reached.

Step 3: pick up a tea sachet and add in kettle ( not sure how to Programme to pick only one sachet).

I would really appreciate any help you can provide. Thanks a ton.

Also I am based in Uk so any advice on where should I buy required hardware from would be highly appreciated.

I suggest that you build a model of the arm first, without servo motors. Then you can check which torque is required for which task. A string balance can measure the force, which multiplied by the distance to the motor will give the required torque.

Thanks for your reply. As I mentioned I am new to robotics. I do not think that I would need a lot of torque as the arm will only pick a tea sachet of approx 10 grams. Based on this, which arm would you recommend. Also which board should I buy to control servos. Thanks for your help

I also think that the connected water pipe will make your project much more expensive.

For only a temperature sensor and tea gripper you can use any robot arm that can span the distance between the tea store and kettle. Take care for the gripper itself, which requires a certain torque unless already contained in the robot arm kit.

Thanks. Appreciate your help