What did I make?
T.A.B.U. is a crab like robot that runs on the arduino uno micrcontroller. T.A.B.U. stands for "Testable Arduino Based User-system". I developed this robot so that I could continue to learn how to code robotics with a phisical test subject.
How did I make it?
T.A.B.U. runs off of three 9v smoke detector batteries, one for the board and base servo, one for the left claw, one for the right claw. It is a very simple robot to make and is a great entry level project. When you are finished you will have an opensource robot that you can program and add to to suit your needs.
Where did I make this?
I worked in my room. I have a personal workdesk and I have spent countless hours working in there.
What did you learn?
This project really helped me understand how robotics function in a safe and testable enviorment. I want others to have the ability to use my robot to enhance their skills with electronics and robotics.
I recomend that if you have an intrest in Arduino programming you pick up a copy of the "Arduino Cookbook" by Michael Margolis. This is a key to debugging and learning the system.
Well enough of that, let's get started!
Step 1: Materials...
For this project you will need the folowing...
- soldering iron/gun
- drill bit for drimmel
- cutting blade for drimmel
- needlenose pliers.
- super glue
- 2 by 3 foot sheet of plexiglass or poycarbonate board
- one small breadboard with 2 power rails (+/-)
- 3 9v batteries
- 3 9v battery holders
- jumper wire
- two (L) brackets
- one (V) bracket
- set of four window blind bracket (can be replaced with plastic cube of any kind)
- set of 6-32 x 1/2 bolts, nuts, and washers.
- 3 parallax 180 degree servos (larger model)
- one round battery plug that will work with your model of microcontroller
- three LED's
- Perf board
And finally, last but not least, an Arduino compatible microcontroller.
I was able to create this robot using around $120, However I owned all the tools and allready had an arduino board.
Step 2: Creating the Bases and Legs
Before we get started I want to point out that this project is opensource, meaning that if you want to change the shape or size of a part you can do so.
Once you have aquired the plexiglass or polycarbonate board you need to grab a sharpie and a measuring tape. You will need to cut an octagon with 3.5" sides, If you would rather you could also cut a circle with a 7" diameter.
Next you will need to cut four 6x5x2" triangles out for the legs. Be carefull when cutting the board because the plastic shards will shoot right up into your face. I recomend using goggles.
Next cut out two 3x1" rods for the legs.
Finally you need to cut out the platform for the Arduino witch is a 1x3" rectangle.
Finished? Congratulations, the hardest part is over!
Step 3: Attaching the Servos to the Base
In order to attach the servo to the base of the robot you will need to cut a hole large enough for your servo to sit in the center without falling through. when you cut the hole make sure that the servos rotaion is at the center of the base. Otherwise you won't have a balanced robot. Then use the screws that came with the servo to attach it to the board.
Next you will need to super glue the other two servos to the left and right side of the base. Be carefull not to get any on the gears or your servo will not work.
Step 4: Assembeling the Legs
Now that we have the servos mounted we need to asseble the legs. First attach the rod to the Window blind brackets. Place the rod at an angle between the two brackets and drill two holes. Insert the bolts and the nuts. Now attach the legs to the brackets, drill two holes, insert the bolts and your done. Now all you have to do is attach the leg to the servo with the screw that came with your servo.
Make sure that you do not tighten the bolts two tight or youll split the plastic. Now repeat this for the other leg.
Step 5: Assembling the Base
FIrst you need to attch the bracket to the servo motor using the screw that came with your servo. Then use super glue to attach two more window blind brackets to the legs of the V bracket. these will work as the rotation base for the robot.
Step 6: Mounting the Arduino
Use the super glue to attach the panel we cut out earlier to the top of the servo. Center it over the servo so that the robot can be balanced. Then drill two holes so that you can use the pre drilled hole in the arduino to attach it to the base.
Step 7: (L) Brackets and Eyes
Now You need to attach the (L) brackets to the base using two screws. Make sure the brackets are parallel to one anouther and won't get in the way of the servos motion.
Now you need to attach the LED eyes. Choose four LED's of your choice as the eyes. I used some scrap circuit board but perf board is better. Place the LED's one above the other and solder thier posative and negative ends together make sure you dont hook them up directly to the 9v! This will fry them and they will be useless, also your work room will smell like cigarettes. Ewww!
Note: If you are confused look at the first image in this instrucatble.
Step 8: 9v Batteries
To connect the 9 volts you need three holders. Set them all next to eachother on the base behind the servo opposite of the (L) brackets. Next xcrew all of them in and make sure that you don't offset the wieght of the base. Change the location of the holders if you need to in order to keep the robot balanced.
The left and right batteries should not be soldered to any thing, while the center battery should be wired tpo the apropriate battery converison that allows you to power your arduino. Once you have that soldered correctly and have tested the power to make sure it works I recomend adding a plastic cover around it to prevent shortciruiting and frying of the Arduino board.
Note: Make sure you can easily remove and replace the batteries easily.
Step 9: Breadboard / Power Rails
For this step all you have to do is find a place on your base for the bread board to sit. Then attach the power rails ontop of the left and right servos. These will allow easy accsess to the power and ground. Most breadboards allready have an adhiesive on it, if yours does not use super glue to attach it.
Step 10: Wire the Power and Ground Rails / 9v
Time to start wiring!
- connect the Arduino 5v to the right power rail and the ground to the ground rail
- connect the left ground to the left ground rail and the right power rail to the left power rail
- connect the left and right 9V to the breadboard
- connect the left ground rail to the left 9v ground, and the right ground rail to the right 9v ground
- connect the left power and ground to the breadboard
- plug in the servos to yhe breadboard, make sure that the power and ground are in the correct position
- connect the LED's to pin 13
- connect right servo to pin 9, and the left to pin 8
- connect the base servo to pin 10
Step 11: Test!
You have finished your own T.A.B.U. testable robot. Now go out and actually test it! Write some custom code and test it. Most importantly learn! The main purpose of this robot is to allow people to understand robotics simply and enjoy a fun and simple programming user-system.
Thanks for viewing and please leave a comment / picture of your T.A.B.U.