Introduction: Let's Build a Robot!
I've been building stuff like this since I was about ten or so years old... and I love it!
It's amazing how fabrication techniques have improved in the last few years. Inexpensive hardware, 3D printers, and awesome boutique electronics stores like Adafruit, SparkFun, and Seeed Studio have opened a Pandoras-box of Awesome.
Are you ready to build your robot? Please make sure to read through the entire Instructable before making any purchases - parts are listed throughout.
If you have any questions, let me know - I'll do my best to help. Want to see ROBOB (ROB-OB) in action?
Ding ding ding... let's go!
Step 1: 3D Part Printing
Here's a link to the model on TinkerCAD...
Are you new to 3D printing? Printing all these parts is going to take a good chunk of time - the bigger your build platform the better. To save you a little bit of time, I've broken the model down into printable parts - get all the bits-n-bytes over at Thingiverse.
Like I said, you can use PLA or ABS... here are the types I used.
Blue Pro-Series PLA
White Pro-Series PLA
Natural Pro-Series PLA
Step 2: Servo to Arm Connector
Here's a little nugget that might help you manage the transition from printed parts to injection molded / metal parts.
I originally tried to print a mount... to connect the bolted revolute joint directly to the servo. It was all kinds of wobbly - and didn't work. The vertical shear-strength and tolerances of printed parts just weren't going to cut-it.
I decided to 'integrate' the nylon connector that comes with the servo into the print... bingo!
You'll need to trim the servo horn down a bit and then snap it into the mate. Then, glue the two parts together and you have a very strong and reliable transition from the servo to your printed arm. Use the tiny screw provided with the servo to attach the arm to your robot.
Do you know where robots keep their armies? ...up their sleevies.
Step 3: Arms Assembly
You'll need a eight #6-32 PC screws to attach the digits to the hand; three digits on one side and one for the thumb. The hand is isometric, 'flip' assembly for the other over and you're good to go. You're making great progress - give yourself a hand!
StarTech #6-32 PC Screws
When the hand is done, move-on to the forearm. I found an odd connector in my wife's scrapbooking box... and decided to use it with the bolted revolute joint. It turned out kinda cool.
1/4 inch Chicago Posts
When connecting two bolted revolute joints together - put a nut in one and a screw in the other and twist the them together. Use a screwdriver to adjust them to a sweet-spot; not too loose or too tight.
M3 Nut / Screw Set
Top the arm with the connectors you completed in the last step.
Step 4: Feet and Legs Assembly
This is a quick and easy step... assembling your footies. Grab the foot cap and apply the color accent with a bit of super-duper glooper.
Flip the cap over and fill it full of something heavy. I'm using washers from our local home improvement store; buying a box is typically less expensive than buying onsies or twosies.
When you're ready, snap the base and cover together and use some 1/2 inch chicago posts to hold the foot to the leg.
1/2 Inch Chicago Posts
Step 5: Torso Assembly
Super-duper glooper the torso base, belt, and mid-section together... I get the parts almost together except for a little space and then let the glue 'wick' into the groves; hold for 30-40 seconds.
You'll need to decide where you want to drill a hole for the power - I used a 15/32 inch drill bit. Don't go to fast, you might melt and/or crack your part.
2.1 mm Panel Mount Barrel Jack
Add the leg plate and bolt the torso to the leg loop.
When we get to the electronics you'll see why I decided to add the Adafruit logo.
Next are the shoulder caps and neck ring.
Do you remember how we glued the servo horn for the arm connector? Here is the same approach with the head. When you get this done, add the servos... they should snap into place; you'll need three. Two for the torso and one for the head/neck.
Turnigy 9g Servos
Arrrrms... matey - add the arrrrrms and torso cap.
Step 6: Head Assembly
Screw that puppy in place... why do we say 'puppy?' Why not wombat or kiwi?
This crazy looking three-armed-thing is a transducer - which we'll mount in the head. It's a kind of speaker... more about that later.
Insert the 8x8 LED matrix into the eye socket and add some M3 screws to hold it into place... or glue it - whatever suits you.
Mini 8x8 LED Matrix w/I2C Backpack (blue)
Glue the mouth ring to the head cap - what's that crazy thing with the wires coming out of it? We'll cover that in a bit. Close up the head and it should fit nice and snug against the torso.
Step 7: Electronics
It's time to transform your robot into an Internet of Things!
You'll need power, something to drive your servos, a 'brain,' LEDs, a 'voice,' and an audio amplifier for starters.
5V 2A Power Supply (good)
5V 10A Power Supply (best)
16-channel Servo Driver
3.7 Watt Stereo Audio Amplifier
EMIC 2 Text to Speech Module
Argh! My batteries need recharging... I will have to continue this Instructable next week! Stay tuned!