Connect Servos
Last updated
Last updated
In this step we will connect the Motors, Servos, and run the cable for the Ultrasonic Sensor to the Spirit Main Board.
The image above is given for reference. Refer back to this image to see what pins should connect to what parts. These labels are printed on the bottom of the Main Board, though half of them cannot be seen once the Main Board is mounted to the frame. Use this image as reference if needed.
Take a minute to study the markings in the image above. The following items can be connected to this header, generally moving from left to right, and top to bottom.
Right Motor
Left Motor
Infrared Transmit LED (not supplied with kit, for future expansion or DIY solution)
Ultrasonic Rangefinder (along the top row)
Tilt Servo (top row, right end)
Grip Servo (bottom row, middle)
Pan Servo (bottom row, right end)
WARNINGS:
IT IS POSSIBLE TO CONNECT ITEMS TO THIS HEADER BACKWARD. TAKE SPECIAL CARE TO CONNECT CABLES CORRECTLY. CONNECTING CABLES REVERSED CAN CAUSE DAMAGE.
Take special care to connect parts to the correct pins as described below.
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Connect motors to the header. Note there is a "Positive" side and a "Negative" side of each pin. The Positive side has "POS" printed on the board, and the Negative has "NEG" printed on the board. Connect each motor so the red wire is on POS and the black wire is on NEG
Important Notes:
Each motor connects across the header from top to bottom.
The direction is reversed between the two motors
Carefully study the image above, play attention to where each color is.
Carefully route the motor wires under the Raspberry Pi board as shown.
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Before connecting the servos, take a minute to mark the end of the wire of the Grip servo. Remember the Grip servo is the forward most servo, and the Pan servo is directly behind the Grip servo. The Tilt servo hasn't been added yet. Mark the end of the Grip servo so you can identify it in the next step.
Carefully route the servo wires behind the long spacer that connects the upper and lower frame plates. We suggest folding the cables back on themselves one time. This will take up the extra slack and allow the cables to be neatly stowed under the Raspberry Pi board. Use tweezers to help move the cables around. Be careful to not damage parts on the bottom of the Raspberry Pi with the tweezers.
Connect the servos to the header as shown.
VERY IMPORTANT NOTES:
The servos have a specific polarity (they need to be connected the correct direction). Each servo has two power wires, these are the brown and red wires, and each servo has a signal wire, this is the orange wire. Carefully study the connection above and make sure the signal wire connects to the pin labeled on the board with "SIG".
Be sure servos connect to the pins as shown above. The Pan servo should connect to the outer most 3 pins, and the Grip servo should be connected directly next to the Pan servo.
Both servos should be connected to the rear most line of pins.
There is just enough room to slide the servos all the way down onto the pins, clearing the plastic frame. You may have to wiggle them into place to get them to clear the frame.
Temporarily connect the third servo. This is the Tilt servo. Again look closely at the orientation of the servo connector from the image above. The orange SIG line should be on the outer most pin as shown above.
