One of the main projects at Fri3d camp is building your own bipedal robot, loosely based on the Otto bipedal design.
In order to power the 4 Servo motors we designed a jewel which houses its own charger and 2 boost converters to 5V.
Careful assembling the feet, don't push in the center, but at the sides or you risk breaking the wood
After assembling the feet and hips and before fitting everything together, calibrate the motors
Connecting the motor wires
G = Brown + = Red S = Orange
Servo 0 = Left ankle Servo 1 = Right ankle Servo 2 = Left hip Servo 3 = Right hip
Install calibration program
where do I find the calibration program?
If you have installed the Fri3dcamp library inside the arduino IDE, you can find the calibration under the following menu item: File > Example > Fri3d Camp Badge > 4.Kits > RobotKit > MotorCalibratie
how to calibrate the servo's?
Once the calibration program has been flashed on the badge (use USB port of Badge, not on motor controller), you will be able to calibrate the servo's.The following buttons can be used to navigate and manipulate the application: BOOT : Go to the next step in the progress (the step you are in is visible as the number of LEDs lit in left displays) BTN 0 : Up BTN 1 : Down
Choose the servo to calibrate (S0/S1/S2/S3 is shown on right display). First calibrate the hips (servo 2 and 3), attach the legs. Calibrate the ankles(0 en 1) and attach them to the legs.
The servo moves to the 0 degrees position (left display shows "-") -> mount your leg/foot accordingly, or press BTN0/1 to adjust.
The servo moves to the 180 degrees position (left display shows "+") -> mount your leg/foot accordingly, or press BTN0/1 to adjust.
Save your changes (with buttons select "V" on right display instead of "X" on left display)
what is best assembled, what unassembled or temporary assembled during calibration?
The bot kit is best assembled up to the stage where you have 2 feet, 2 hips and the body. The best way it seems is to pull the servo wires already into place through the hips and the body, but keep the kit partially disassembled. You can take on of the spare horns to help you with determining the 0 and 180 degrees positions.
What is 0/180 degree reference (left or right, direction w.r.t. robot, mirrored or same for left and right motors?
If you take the servo in front of you, the servo wire leading away from you, left is 0 degrees, right is 180 degrees, for every servo.
Do I lose my calibration if I install another application on my Fri3d Badge?
The servo calibration is stored at the badge level in the persistent memory of the badge. This means that another badge will require you to recalibrate your servo's, but you will not lose the calibration if you just flash another application on it.
Can I calibrate an assembled robot?
Calibrating an assembled robot can be a bit hard. The problem being that the servo's of an assembled robot do not have the full range of 180 degrees to move, resulting in wooden parts locking into eachother. Not saying it is impossible, just saying you have to watch out.