[Project] Arduino Bluetooth Robotic Arm

Moonzy · April 22, 2016

Hello,

I'm trying to build a robotic arm with 1 gripper, 5 Servo motors, 1 arduino, and one HC-05 (or HC-06) module

these are the basic things i have to work with

Spoiler

i would like to discuss while im building this project (plan to build it overnight)

I know the basic of servo motors and arduino, but ive never played with bluetooth on arduino before so i might need some guidance there

My current questions:

1. how thick of a wire do i need to connect my battery to my 5x servo motors and arduino? (servo motor model is HD-1501 MG), i dont have any low gauge wires `-`

2. how should i power my arduino with this 6V SLA battery?

3. Can i know the basics of bluetooth for arduino? i heard i need 3 of the same resistor to reduce the TX pin voltage coming out from arduino since its 5V, i need to make it to 3.3V for the bluetooth module to work and i need to remove TX or RX pin while programming the arduino or it wont work? im really clueless in this field

4. How do i make an android software to control the servo motor? i was thinking two buttons for each servo "+" and "-" to add and reduce the angle, but i have never made an android app before

or if there are any ready made android app that allows me to control 5 servo and 1 gripper (two input for open and close)

I bet there are more questions that i will have to find out as i progress ill update the question list as i progress

So far i've assembled the arm as shown in the picture, though i need to find a way to attach the gripper to the servo motor, im thinking of 3D printing a coupling or something but if there are other ways, i'll consider it

this is going to be a loooong night for me `-`

Huntsman · April 23, 2016

1. Not very thick, just normal 20 gauge from PSU will do fine. I have the same servo. They run fine on 6V actually, so connect power directly from battery is fine.

2. You cannot directly power the arduino from that battery, unless u have 2 of them. This is because the Arduino is a 5V component, maximum 5.5V tolerant. The integrated voltage regulator will only work from 7.5V input and above. So what you should do is either get a LDO voltage regulator or a SMPS buck regulator to bump down the voltage to safe 5V.

3. There are numerous guide and libraries out there for bluetooth with arduino so Google them up. If your UART(tx rx) is only 3.3v tolerant, you need a logic level shifter. You can buy these modules readily from ebay, sparkfun or any electronics hobby shop. Alternatively, you can make one yourself but certainly not with only resistors. Schematics are available online.No

4. No idea about android as I'm only starting to learn those. But I've seen ready made apps in play store. They cover quite a large range of function so check them out.

5. 3D printing is expensive. Even more so if you don't already know how to draw the designs out in CAD software.

I'll try to link in some more details and urls later on. Almost time for my shift to end Goodluck!

Moonzy · April 23, 2016

7 hours ago, Huntsman said:

1. Not very thick, just normal 20 gauge from PSU will do fine. I have the same servo. They run fine on 6V actually, so connect power directly from battery is fine.

2. You cannot directly power the arduino from that battery, unless u have 2 of them. This is because the Arduino is a 5V component, maximum 5.5V tolerant. The integrated voltage regulator will only work from 7.5V input and above. So what you should do is either get a LDO voltage regulator or a SMPS buck regulator to bump down the voltage to safe 5V.

3. There are numerous guide and libraries out there for bluetooth with arduino so Google them up. If your UART(tx rx) is only 3.3v tolerant, you need a logic level shifter. You can buy these modules readily from ebay, sparkfun or any electronics hobby shop. Alternatively, you can make one yourself but certainly not with only resistors. Schematics are available online.No

4. No idea about android as I'm only starting to learn those. But I've seen ready made apps in play store. They cover quite a large range of function so check them out.

5. 3D printing is expensive. Even more so if you don't already know how to draw the designs out in CAD software.

I'll try to link in some more details and urls later on. Almost time for my shift to end Goodluck!

1. ill test out the wires i have first, im im using that wire connected to the breadboard and using the breadboard to distribute the power to 5 servos lol

2. mmm yea, i just figured ill use smartphone's battery bank `-`

3. mmm guess ill need to do more research

4. will do, but theres just so many @~@

5. well my school provides 3D printer with the filaments so ill be fine lol

thanks