A small Astromech droid I decided to make
--> finishing up the .ino control code, but hardware and ESP32 code is finished!
Designed with the R4 Astromech droid in mind, but getting lost along the way resulted in R4-04, the droid for a galaxy not so far away.
This droid hosts its own WiFi network, and anyone in reach can accesss a web server holding a livestream of the IP camera and controls for the droid.
The IP of the droid's control server is printed on the bright blue LCD screen.
The droid is controlled using websocket communication on the ESP32 and relays information from the user to an Arduino Mega controlling the motors via I2C commands. The Arduino also handles a self balancing routine, adjusting its shoulders with PID so that rougher terrain won't be a problem.
Along with the motor control, R4-04 also shows information concerning its environment on a second screen. The information is obtained via a BME280 Sensor.
The control buttons are implemented using websocket communication.
Each button is given a specific ID command, which is passed through to the ESP32's I2C wires and sent to the arduino.
Upon a new command event on the I2C wires the Arduino will perform the desired motor operations.
--> a CSS Transform on the img and possible pretty-ing up of the UI should be done in V2
ESP32 Components:
ESP-CAM
ESP-WiFi
SPIFFS
freeRTOS
I2C Driver
HTTP-Server
IDF-Version:
ESP-IDF v4.4-dev-744-g1cb31e509
Arduino:
Unistep2
AdaFruit BME280
GY521
Wire
U8G2Lib
AI-Thinker ESP32-CAM
Arduino Pro Mega 2650
I2C 1602 LCD (blue)
I2C 1.3'' LCD Screen (white)
GYU-521 Accelerometer and Gyroscope
BME280
28byj-48 Stepper motor and 2003 ULN Driver (X3)
L298N DC Motor Driver
DC "TT" Motor and wheel (X2)
5V 30mA Mini Solar Panel 50x33mm (x2)
4.8V NiMh 2200 mAh Battery (x2)
608 Abec 9 Bearings (x8)<br>
M4 X 30mm Screw and nuts X 6
M3 x 35mm Screws X 4<br>
M3 X various smaller sizes X 16
5/16'' Bolt and nut (2.5+inches) X3
Springs that fit over the 5/16'' bolt (these are optional but help)
Dupont Wires (Mostly Female to Female, but a Few male to Female)
Various proto boards cut to size
some passive components listed in the schematic
Epoxy glue
Hot glue
Solder
PETG (testing parts took a lot of filament, not sure what the end result requires, also PLA should be fine)<br>
3D printer (designed with the ender 3 in mind)
Soldering Iron
Screwdriver
Hot Glue Gun
Files / post processing tools
Wire cutter
A ventilated area
Socket Wrench / Sockets come in handy
Something to spread epoxy with
Hacksaw
Printer: Creality Ender 3 pro V2
Filament: Duramic PETG
Infill: 20%
Support: 2% everywhere
Temp: 235
Slicer: Cura
--> Slow on the first layer
--> PLA Should be just fine for the parts as well, i just had PETG because it was cheaper at the time.
I designed the droid using FreeCAD, which is free and works on all major OS platforms.
You are free to edit / change all designs, but please give a reference to the original!
Printing all parts goes like this:
2 droidSolarPanelHolder1.stl, 1 of all others in the UPPER folder (head / neck)
2 legs, 2 Shoulders, 2 FourthLeg_body.stl (Stepper holders), and 1 of each on the rest in the MIDDLE folder. (main body)
2 droidFoot1.stl, 1 of each 3rd foot component in the LOWER folder. (lower assembly)
The TT motor and wheel attatch to the foot using M3 X 35MM screw and nuts. The leg is attached using 2 bearings and a 5/16'' bolt and nut.
There is a hole for the wires in the middle of the foot, as well as a space for them to fit on the side of the leg.
The backside view of the droid. There is a door that utilizes an M3 X 20 screw to hold both pieces in place. Springs are attached from the stepper motor's M4 screw to the Foot's 5/16'' bolt. These are optional but help the droid remain standing under its own weight. The M4 screws I used hindered the neck from reaching the gear, this will be fixed in V2.
There is a stepper motor with the smaller neck control gear attached to the top of the body using M4 screw and nuts.
The neck assembly is glued into place on the head and is not glued to the body. SDA,SCL, 5V, and GND are run through the neck to reach the ESP32-CAM.
The Front foot uses 4 bearings and an M3 x 8mm nut and screw that fits in the middle. Along with 2 5/16'' bolts to hold the wheel and leg in place. The springs are attached on the outside of each bolt which help restrict the freedom of movement.
As with everything, theres always something to upgrade or clean up.
Here's a list of things I've thought of to work on if a second version is going to be built.
Hardware upgrades:
Voice Recognition Module (elecHouse)
Buzzer
Stepper motor for 3rd Leg
Distance Sensors
More Environmental Sensors
**POSSIBLY** Replace ESP32 with orange/Raspberry Pi
Arc Generator (would also require Linear Actuator)
Change DuPont wires to something that connects better (MOLEX/JST/something)
***Fix up power components** (5V is being fed through the Arduino's Regulator, causing current bottleneck)
Software Upgrades:
Web app CSS needs to transform the Image vertically and make things prettier
Send Environmental Data to web UI
logging??
Give additional hardware options on web UI
train elecHouse voice module to recognize commands
Mechanical Upgrades:
Combine 3/4ths of the body into 1 .stl
Body can be taller
create spaces in body for hardware components (slots, screw holes, etc.)
Figure out a 3Rd leg drive mechanism (leg also needs to fit in the body)
change direct stepper connection to shoulders into something better (timing belts??)
This R4 Unit is a personal voyage in learning freeCAD and helped me form a new curriculum for a Robotics Class.
Also, I wanted another ESP32-CAM project, they're too much fun!
It is not in any way meant to represent work of Disney, Star Wars, or any legal stuff. I don't know how to put this correctly, but its not a 501st worthy model. But still fun to build!