Starrley hexapod is derivative of Vopal hexapod. Our design is nest and compact which means it has less time to print one set. The board we use makes the wiring and assembly more easier. With internal battery charging circuit, you don't need to remove the battery for charging. To control and play, you can use the original gamepad of Vopal hexapod or the battery rechargeable gamepad we design as shown in the demo video. Starrley and Vopal are different in shape but are functionally the same. Information in Vorpal wiki can mostly apply to Starrley as well.
To build Starrley you need following components:
- a HuaDuino board, it is Arduino Nano compatible with enhanced features. It integrates everything on a single PCB. It's a lot easier for people to make a bot with it. Embedded battery charging circuit, battery charging is more convenient. It is inexpensive so it is our favor board to do project.
- 12 of Tower Pro MG90s or compatible servos.
- a HC-05 Bluetooth module, set the baud rate to 38400; you will need one more for the gamepad.
- a buzzer.
- a 10K Ohms potentiometer.
- a 18650 lithium battery; the sample unit we built is a 3000mAh one; use this battery clip to hold it; practically you can any 3.7V lithium batteries as long as the size can fit the base model. Some 3.7V polymer lithium batteries have protection circuit which limits the output current so it is not recommended unless you have the skill to remove it or bypass it by soldering two extra wires directly to the battery terminals.
- 12 of M2x6 tapping screws.
Arduino sketches on github - opens and uploads
The connection of components to the board as followings
- front right hip servo -> D9
- front right leg servo -> D8
- front left hip servo -> D10
- front left leg servo -> D11
- mid right hip servo -> D6
- mid right leg servo -> D4
- mid left hip servo -> D7
- mid left leg servo -> D5
- back right hip servo -> D3
- back right leg servo -> D2
- back left hip servo -> D13
- back left right servo -> D12
here is a good tutorial for understanding potentiometer
- VCC - > 5V pin
- Signal -> A3
- Gnd -> Gnd
- positive polar -> A2
- negative polar -> Gnd
HC-05 BT module
- plug it to the 6 pins socket and move the S1 switch to BT side (after you upload the robot code)
Assembling Notes -
- initial posture of Starrley is stance (as the photo) which all servos are in initial angle 90°. When applying the servo arm and screw you must the turn the robot on to allow the robot code to turn the servos to 90°, then adjust the hip and leg part to form the stance;
- before applying the screw to potentiometer, the knob should be turned all the way counter clockwise down to the end where it should point to the word "STOP" on cover. Starrley will be on stance when turned on;
- while tested everything are all right, you can put the cover on and applying a M2 tapping screws to the front and back sides;
How to Play -
- Turning potentiometer knob clockwise to the position pointing TST label, Starrley will perform demo mode as shown 1st video;
- Turning the knob clockwise and pointing to RC label, Starrley can be controlled by the gamepad as 2nd video does. Before that, the HC-05 (in master mode) of gamepad and the one (slave mode) in Starrley needs to pair up together . To do that brings it and gamepad as close as possible, then turns both power to on. It will take few seconds. When paring is successfully, gamepad is ready to drive Starrley. Pressing the joystick you will see Starrley to move.
Battery Charging -
Connects 5V power source to the USB port, you will see LED red light while charging. When charging finishes, the LED will be green.
- print 3 pairs of hip and leg