Servo - December 2010

the offset of the servo drive shaft. While there is technically no “front” or “rear” of the ArdBot, for the purposes of assembly, the top of the illustration in Figure 5 is the front and the bottom is the rear.

Step 1

Insert a servo into a servo mount by sliding it back-end first through the mount. The fit may be tight, depending on the make and model of the servo. (As necessary, enlarge the rectangle for the servo using a file or coarse sandpaper.) Do not force the servo into the mount or the mount may be damaged.

Secure the servo to the mount with 4-40 x 1/2” screws and hex nuts (Figure 6). You can use four screws for each servo, or only two. When using two screws position them on opposite corners of the servo mounting flange, as shown.

Repeat for the opposite servo and mount. Be sure to construct the second servo and mount in a mirror image to the first! Refer to Figure 9 in Step 3 to see how the motors should be inserted into the mounts. For reference, also see Figure 12 for an aerial view of the ArdBot and its completed bottom deck.

FIGURE 4. Layout pattern for cutting and drilling the servo mount. You’ll need two of these. If cutting the inside rectangle proves difficult, you can instead make the mounts by cutting through at the dotted line. The mount will be a little more fragile, so handle it carefully.

Use all four screws to secure the servo in the mount, rather than just two.

Insert the machine screws through the L bracket, then through the servo mount. Secure on the other end with a nut. Before tightening, be sure the bottom of the L bracket is flush with the bottom edge of the servo mount.

Step 2

Using 4-40 x 1/2” machine screws and nuts, attach two plastic L brackets to each of the servo mounts (Figure 7). You’ll be make a “left” and a “right” mount assembly.

For the left mount assembly, the motor shaft should face to the left and toward the “top” of the deck (as referenced in Figure 5). Attach the L brackets to the right side of the mount. For the right mount assembly, the motor shaft should face to the right, also toward the top of the deck. Attach the L brackets to the left side of the mount.

Step 3

Attach the left mount assembly to the bottom deck using two 4-40 x 1/2” screws and standoffs. The screws should come up from the underside of the deck, through