Adding the Components
Let's now add the main PCBs to the torso.
This part is pretty easy to follow, but don't try to skip any steps !
1 - The Motor Driver
We'll first add the Motor Driver, which is the PCB responsible for controlling the 12 motors of the robot.
For this part, you'll need :
| Ressource | Quantity |
|---|---|
| Motor Driver PCB | 1 |
M2.5 x 4mm screws | 2 |
Place the Motor Driver
Place the Motor Driver on the top-left side of the torso as shown.
Make sure to orient it correctly :
- The 4 motor connectors should be towards the back of the robot.
- The 2 main connectors should be towards the front of the robot.
Screw the Motor Driver
Screw the Motor Driver to the torso using two M2.5 x 4mm screws.
Place the screws in the two holes of the PCB labeled with the 
You don't need to screw the Motor Driver super tight, just make sure it's secure and doesn't move around.
2 - The Analog Reader
We'll then install the Analog Reader.
It reads the feedback from the 12 motors as well as the 4 contact switches, and send it to the Main PCB.
For this part, you'll need :
| Ressource | Quantity |
|---|---|
| Analog Reader PCB | 1 |
M2.5 x 4mm screws | 2 |
Place the Analog Reader
Place the Analog Reader on the top-right side of the torso as shown.
Make sure to orient it correctly :
- The 4 motor connectors should be towards the back of the robot.
- The main connector should be towards the front of the robot.
Screw the Analog Reader
Screw the Analog Reader to the torso using two M2.5 x 4mm screws.
Place the screws in the two holes of the PCB labeled with the
As for the Motor Driver, you don't need to screw the Analog Reader super tight, just make sure it's secure and doesn't move around.
3 - The Paw Boards
We'll now add the two Paw Boards, which make the interface between the PCBs and the motors of the legs.
They distribute the power to the motors and pass the signals from the Motor Driver and the Analog Reader to the motors.
For this part, you'll need :
| Ressource | Quantity |
|---|---|
| Paw Board PCBs | 2 |
M2.5 x 4mm screws | 2 |
Place the two Paw Boards
Place the two Paw Boards in the middle of the torso as shown.
As for the other PCBs, the Paw Boards should sit flush with the surface of the torso. If they are not, check their orientation :
- The 6 Motor Connectors (the big ones) should be towards the exterior of the robot;
Also make sure that the Board with the longest wires is placed on the front, and the one with the shorter wires is placed on the back.
Screw the Paw Boards
Screw the Paw Boards to the torso using a single M2.5 x 4mm screw each.
Place the screws in the holes of the PCBs next to the two 
You know the drill by now, don't screw them like crazy :)
4 - The IMU
We'll add the IMU (Inertial Measurement Unit) now, which is the sensor responsible for measuring the orientation and acceleration of the robot.
For this part, you'll need :
| Ressource | Quantity |
|---|---|
| IMU Sensor Board | 1 |
M2.5 x 4mm screws | 2 |
Place the IMU
Place the IMU in the center of the torso as shown.
Make sure to orient it correctly :
- The wires should be coming out of the back side of the PCB, with the two holes on the front side.
Make sure that the IMU is sitting flush with the surface of the torso !
Screw the IMU
Screw the IMU to the torso using two M2.5 x 4mm screws.
Place the screws in the two holes on the front side of the PCB (the side without wires).
You don't need to screw the IMU super tight, just make sure it wont move around otherwise the readings will be noisy and inaccurate.
Verification
Congratulations, you have finished adding the components to the torso !
Here's what the final result should look like at this stage :
Ready for the next step ? Let's move on to Adding the Motors !