AL5A Arm Assembly Instructions Rev. 2.1

If you have not done so before, download and install <a href="http://www.lynxmotion.com/p-567-free-download-lynxterm.aspx" target="_blank">LynxTerm v1.08</a> or higher. Connect the SSC-32 to

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the serial port and apply power. The green LED should light up and stay

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on

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until it receives a valid serial command. Run the LynxTerm program. If

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LynxTerm cannot connect, please consult the <a href="http://www.lynxmotion.net/viewtopic.php?t=4702" target="_blank">serial

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and USB-to-serial troubleshooting guide</a>.

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597

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Now test the servos and connections by selecting a channel, and moving

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the servo carefully using the slider bar. Verify that the servos are

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plugged into the channels as listed in Table 20. Easy does it; this is

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real time control, so be careful! Select channels 0 through 4 one at a time and test that each works.

</td>

Figure 21a (Lynxterm).

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<td style="vertical-align: top;">Step

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21b (SSC-32U / Servo Utility).

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Just like in the base instructions, we will use the SSC-32 Servo

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Sequencer Utility to test the servos and confirm they are all plugged

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into their proper servo channels and oriented correctly. If not done so

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before, download and install the <a href="http://www.lynxmotion.com/p-895-free-download-ssc-32-servo-sequencer-utility-created-using-flowbotics-studio.aspx" target="_blank">SSC-32 Servo Sequencer Utility</a>. Connect the USB

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cable and power the board using the on/off switch. Run

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the program.

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The SSC-32U is shipped with a baud rate of 9600. Ensure the baud rate

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towards the bottom right of the window is set to 9600 (not 115200). The

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software should automatically detect which COM port is connected to the

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SSC-32U, and have installed the <a href="http://www.ftdichip.com/Drivers/VCP.htm" target="_blank">FTDI

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(USB to serial) drivers</a> automatically.

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Ensure Servos 0 4 are checked off in the software (and therefore

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accessible). You can now move the sliders to see each servo rotate. Verify that the servos are

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plugged into the channels as listed in Table 21. Easy does it; this is

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real time control, so be careful.

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For more information, please consult the <a href="http://www.flowbotics.com/manuals/ssc-32_servo_sequencer.pdf" target="_blank">SSC-32 Servo Sequencer Utility manual</a>.

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Figure 21b (SSC-32 Utility).</td>

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</td>

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<td align="left" valign="top" width="50%">Step 22a (SSC-32 / Lynxterm).

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Click on the "All = 1500" button in LynxTerm. This will command the

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servos to hold center position. Your arm should look like Figure 22. If

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any joint is off by more than 15°, then you may have made an error in

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assembly.

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If you did not purchase RIOS software, please proceed to step 27.

</td>

Figure 22.

</td>

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</td>

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<td style="vertical-align: top;">Step 22b (SSC-32U / Servo Utility).

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Click on the "Calibrate" button in the SSC-32 Servo Sequencer Utility.

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A knob next to each servo will appear (figure 22b). This knob is used

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to fine tune the servo's center position. The knob is not intended to

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be rotated: click the knob you wish to rotate, keeping the mouse button

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down, and drag up and down to rotate the knob. Do this for each servo

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until the arm looks like figure 22, and angles are 90 and 180 degrees.

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If

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any joint is off by more than 15°, then you may have made an error in

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assembly.

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Once all servos have been properly positioned, click the icon

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"Calibrate" once again, and the offset values will be stored on the

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SSC-32 / SSC-32U.

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If you did not purchase the RIOS software, please proceed to step 27.</td>

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Figure 22b (SSC-32 Utility).</td>

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<td align="left" valign="top" width="50%">Step 23 (RIOS Users Only).

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To use the RIOS Arm control software, you need to make one

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minor modification. Remove the servo horn screw from the elbow servo.

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Pull the servo horn off the servo, lift the arm two 'clicks' (30°) at

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the elbow and reattach the servo horn and screw. Note, the Hitec spline

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has 24 grooves, so each groove is 15°.</td>

Figure 23.</td>

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<td align="left" valign="top" width="50%">Step 24 (RIOS Users Only).

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At this point the arms is assembled and tested using LynxTerm. If your

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robot came with RIOS, we can now install RIOS and calibrate the arm to

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the software. For those using a different program such as FlowBotics or

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FlowStone, refer to the software's user guide. Use the RIOS Help File

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to calibrate and use the arm.

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Install RIOS, following the

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on-screen installation prompts. The serial number is on the back of the

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CD sleeve.

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Use the RIOS Help File to

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calibrate and use the arm, following Steps 1-7. When you get to Step 8

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in the help file, please use the following instructions instead. Click

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on the "Arm" button, then click on the "Arm" button in the "Arm size"

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section, and then click on the AL5A arm image on the popup screen.

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Please take the time to do an

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accurate calibration. The performance of the arm will only be as good

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as the calibration. If the on screen virtual arm does not match the

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real arm this is a sign of an inaccurate calibration. After calibration

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please study the RIOS manual carefully to learn how to store and

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playback sequences for the arm.

</td>

Figure 24 (RIOS).

</td>

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<td align="left" valign="top" width="50%">Step 25 (RIOS Users Only).

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To calibrate the arm's shoulder servo, click the "SSC-32" button.</td>

Figure 25 (RIOS).

</td>

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</td>

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<td align="left" valign="top" width="50%">Step 26 (RIOS Users Only).

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Select the Shoulder, servo #2. Move the shoulder slider up to move the

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shoulder forward so that it looks like Figure 27-2. Set the Min Deg

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angle -90°. Right click on the slider to set this as the Min Position.

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Now the servo will not go past this value, and the program now knows

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this value is exactly 90° from centered.

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Now move the slider down to move

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the shoulder backward so that it looks like Figure 27-3. Set the Max

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Deg angle to 45°. Right click on the slider to set this as the Max

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Position. Now the servo will not go past this value, and the program

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now knows this value is exactly 45° from centered.

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The next step is to read and

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study the RIOS users guide. It is accessible by clicking on the help

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icon on the main screen or by navigating to the install directory

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(c:\Program Files\RIOS_SSC-32\) and opening the Help.pdf file. This

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manual explains in great detail how to use the arm.

</td>

Figure 26-1 (RIOS).

</td>

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Figure 26-2.

</td>

Figure 26-3.

</td>

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<td align="left" valign="top" width="50%">Step 27.

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To connect springs for load-balancing, replace the servo

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attachment hardware in the locations shown, following the diagrams

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below. Hook the springs together after they're secured.

</td>

Figure 27.</td>

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</td>

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<td align="left" valign="top" width="50%">Step 28.

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The arm assembly is complete. The arm is robust mechanically,

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but the servos can be damaged by improper use. An example would be if

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the arm was told to move to an unobtainable position, like the surface

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the arm is mounted to, or by crashing the arm into itself, or other

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objects. The elbow servo is the most vulnerable because it holds the

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entire weight of the forearm. Load balancing springs should be added to

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reduce some of this load.

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If you purchased FlowBotics Studio,

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FlowStone or FlowArm, you can proceed with the instruction guide(s)

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associated with those programs.

People do not

like holding heavy objects with their arms outstretched in front of

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them. Servo based robot arms don't like it much either. Remember, the

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most important rule for servo based robot arms: Park the arm when not

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in motion! When it's moving or at rest it's usually ok. When it's

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holding an object it should do so for the minimum amount of time

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required to do the job. You can always touch the servo case to see if

it's getting hot.

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