BRAT Biped SEQ Tutorial v1.06XE

> <a href="https://wiki.lynxmotion.com/info/wiki/lynxmotion/download/servo-erector-set-robots-kits/ses-v1-robots/ses-v1-bipeds/brat-biped-seq-b/WebHome/minibipd.zip">minibipd.zip</a></td>

14

15

Image of Biped BRAT.</td>

</tr>

<tr>

</tr>

<tr>

I. BRAT Configuration

</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

30

1.

31

Install the SSC-32 Visual Sequencer. Read the Sequencer's manual. This

32

tutorial is not meant to replace the manual! Connect the SSC-32 to the

33

serial port and apply power. The green LED should light and stay on until

34

it receives a valid serial command. Run the Visual Sequencer program.

35

Step 2.

36

The first step in configuring your robot is to position all the servos to

37

mid-position. This is a quick way to ensure the robot was constructed

38

properly. Click on "All=1.5mS" in the upper left corner.

</td>

Figure 2.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

49

3.

50

Click the "Test" button.</td>

Figure 3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

60

4.

61

Place the robot in a position as close to neutral as possible. Click

62

"Yes" and the robot should go to and hold the neutral position.

63

Your robot should resemble figures 4-2 and 4-3. If the joints are off by

64

more than 15° you may have made an error in assembly. To correct this,

65

you remove the center screw from the round servo horn, pull the servo horn

66

off the servo, rotate until it's aligned, then reattach the servo horn.

67

When you are done, click on the

68

"Stop" then "Exit" buttons.

</td>

Figure 4-1.</td>

</tr>

<tr>

</tr>

<tr>

Figure 4-2.

</td>

Figure 4-3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

91

5.

92

Click on "SSC-32" in the upper left corner. This process

93

configures the software to the servos in your robotic assembly. To do

94

this, the servos' neutral, min, and max positions are defined and the

95

actual angles each joint can achieve are entered.

96

Take time to do an accurate

97

configuration! Your robot will only perform as well as the accuracy of the

98

configuration file it's using. In other words, sloppy configuration will

99

make a sloppy robot when sharing projects.

</td>

Figure 5.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

111

6.

112

Each servo you configure must first be enabled. You simply click on the

113

Enable checkbox. You can move the servo by adjusting the slider bar.

114

You will enable the servos one at a time

115

as you configure them.

</td>

Figure 6.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

126

7.

127

Channel 0 is for the BRAT's ankle on the right leg. Move the slider for

128

servo 0 until the servo is at a 90° angle as shown. Note, the mouse's

129

scrollwheel or keyboard's arrow keys can be used to make fine adjustments.</td>

Figure 7.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

139

8.

140

Right click on the slider and select "Set position as neutral (0°)"

141

from the menu.

142

Note, you can see the actual servo pulse

143

length in microseconds in the "Position" box on the left. This

144

can be helpful to make a pulse offset table for experimenting with BASIC

programming.

</td>

Figure 8.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

157

9.

158

Move the slider for servo 0 until the servo is at a 45° angle as shown.

159

Right click on the slider and select

160

"Set position as min" from the menu as shown in Figure 9-2.

161

Adjust the "Min Deg" box to say

162

"-45°" as shown in Figure 9-3.

</td>

Figure 9-1.</td>

</tr>

<tr>

</tr>

<tr>

Figure 9-2.

</td>

Figure 9-3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

185

10.

186

Move the slider for servo 0 until the servo is at an 84° angle as shown.

187

Right click on the slider and select

188

"Set position as max" from the menu as shown in Figure 10-2.

189

Adjust the "Max Deg" box to say

190

"84°" as shown in Figure 10-3.

191

Move the slider back to 0° before going

192

on to the next servo.

</td>

Figure 10-1.</td>

</tr>

<tr>

</td>

</tr>

<tr>

Figure 10-2.

</td>

Figure 10-3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

216

11.

217

Channel 1 is for the BRAT's right knee. Adjust and set the neutral (0°)

218

position with the knee straight as shown in Figure 11-1. Adjust and set

219

the min and max positions as shown in Figure 11-2 and 11-3. Note, you do

220

not have to change the angles because the knee can reach +/-90°.

221

Move the slider back to 0° before going

222

on to the next servo.

</td>

Figure 11-1.</td>

</tr>

<tr>

</tr>

<tr>

Figure 11-2.

</td>

Figure 11-3.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

246

12.

247

Channel 2 is for the BRAT's right hip. Adjust the hip as shown in Figure

248

12-1 and set the neutral (0°) position. Adjust the hip as in Figure 12-2

249

and set the minimum (-90°) position. Adjust the hip as in Figure 12-3 and

250

set the maximum (45°) position. For clarity, the knees were bent in

251

Figure 12-3.

252

Move the slider back to 0° before going

253

on to the next servo.

</td>

Figure 12-1.</td>

</tr>

<tr>

</tr>

<tr>

Figure 12-2.

</td>

Figure 12-3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

276

13.

277

The robot's right side is now configured. You can now configure the

278

robot's left side. Click on the "Bank 3" button to gain access

279

to channels 16-23. Channel 16 is the right ankle, 17 is the right knee,

280

and 18 is the right hip. Configuring these channels is identical to

281

configuring channels 0-2 with one exception: After you are done with the

282

normal configuration, you must click on the "Reverse" checkbox

283

for these three channels! Make sure all servos are set to 0° (home) and

284

save your work. For this robot, "home" position is with all the

285

servos set to their 0° position. However, any position you leave the

286

sliders in when you save the configuration is how the robot will look when

287

you start Sequencer. In other words, "home" position does not

288

have to be the 0° position, that's just what we used. Save your work. The

289

.cfg file will need to be loaded each time you run the program. If you

290

only have one robot to set up, save over the "ConfigSSC32.cfg"

291

file. However, if you plan on using the sequencer with more than one

292

robot, then input a new file name, such as "BipedBRAT.cfg" It's

293

important that you save these files in the install directory, default

294

C:\Program Files\Sequencer_SSC-32\</td>

Figure 13.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

305

14.

306

Now we're going to import a pre-made project. This will enable you to use

307

other people's projects on your robot.

308

Download <a href="https://wiki.lynxmotion.com/info/wiki/lynxmotion/download/servo-erector-set-robots-kits/ses-v1-robots/ses-v1-bipeds/brat-biped-seq-b/WebHome/minibipd.zip">this

309

zip file</a>. It contains several projects. Unzip it into the SEQ install

310

directory. By default, it is C:\Program Files\Sequencer_SSC-32\

311

Click on "Project" in the upper

left corner.</td>

Figure 14.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

322

15.

323

Click on "Import," then select "biped6-long stride.csv"

324

and click "Open," then "OK."

325

Enter a project name or leave the

326

default, then click "OK." You should see an "Import

success" message.

Click "Exit."

</td>

Figure 15.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

339

16.

340

Now for some fun! Let's make that robot walk!

341

Click on "Sequencer" as shown

342

in Figure 16-1.

343

From the drop down menu in the project

344

section, select "biped6-long stride."

345

In the Play menu, click on "Project

346

Loop" as shown in Figure 16-3. Caution, the robot will start moving

347

immediately. To stop the robot, click on the black "stop" or

348

"pause" buttons.

349

If everything went well, your robot

350

should have walked across the table. If it appears that the legs are

351

moving in the same positions, you may have forgotten to reverse the servos

352

on the robot's left side.

</td>

Figure 16-1.</td>

</tr>

<tr>

</td>

</tr>

<tr>

Figure 16-2.</td>

Figure 16-3.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

375

17.

376

Refer to Table 17 for a list of the projects included in the zip file and

377

a video link when available.

378

After you're comfortable with playing

379

projects, you can consult the Sequencer manual for more information on how

380

to create your own. Remember to send us images and videos of your cool

381

projects so we can publish them online!

</td>

<td >

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Project

393

File</td>

394

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Video

Link</td>

</tr>

<tr>

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Balance

399

on Ankle</td>

400

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv04.mpg">Video</a>></td>

401

</tr>

402

<tr>

403

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Balance</td>

404

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv06.mpg">Video</a>></td>

</tr>

<tr>

</tr>

<tr>

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Get

412

up from Back</td>

413

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv05.mpg">Video</a>></td>

414

</tr>

415

<tr>

416

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Get

417

up from Front</td>

418

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv01.mpg">Video</a>></td>

419

</tr>

420

<tr>

421

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Headbutt</td>

422

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv07.mpg">Video</a>></td>

</tr>

<tr>

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv03.mpg">Video</a>></td>

427

</tr>

428

<tr>

429

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Long

430

Stride</td>

431

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv08.mpg">Video</a>></td>

</tr>

<tr>

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv09.mpg">Video</a>></td>

</tr>

<tr>

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF"><<a href="https://www.lynxmotion.com/images/video/bp6srv02.mpg">Video</a>></td>

</tr>

</tbody></table>

</div>

</td>

</tr>

<tr>

<td >

Table 17

</td>

</tr>

</tbody></table>

</center>

</div>

</td>

</tr>

<tr>

</td>

</tr>

<tr>

II. Creating a Walking

Sequence

</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

470

1.

471

Run the Sequencer program.

472

Select the "empty" project from

473

the Project drop down menu, and click on the black "+" to make a

474

new project. Enter a name for your project. As we are making the robot

475

walk, a name such as "BRAT-Walk" might be applicable.</td>

Figure 1.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

484

2.

485

Now we're faced with an empty project and a screen full of servo blocks.

486

To make the screen more manageable, click on "Swap" at the top.

487

This will swap the selected servos with the unselected ones. Since no

488

servos are unselected, this will clear the screen.

489

Now just click on the servos that you

490

need, which should be servos 0, 1, 2, 16, 17, and 18.</td>

Figure 2.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

499

3.

500

You can click and drag the servo boxes to arrange them so they resemble

501

the robot's physical layout.</td>

Figure 3.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

511

4.

512

You can also name the servos by clicking on the number in the servo box.

513

It will bring up the screen in Figure 4. In addition to naming the servo,

514

you can change the color of the servo box.</td>

Figure 4.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

523

5.

524

Now we're almost ready to make the robot walk. First, here's an outline of

525

the walking sequence. The last two steps are just mirror images of the

526

first two steps.</td>

<td >

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Step

537

1</td>

538

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Shift

539

weight to robot's right</td>

540

</tr>

541

<tr>

542

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Step

543

2</td>

544

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Step

forward</td>

</tr>

<tr>

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Step

549

3</td>

550

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Shift

551

weight to robot's left</td>

552

</tr>

553

<tr>

554

<td align="center" bordercolor="#808080" bgcolor="#C0C0C0">Step

555

4</td>

556

<td align="center" bordercolor="#C0C0C0" bgcolor="#FFFFFF">Step

forward</td>

</tr>

</tbody></table>

</div></td>

</tr>

<tr>

Table 5.</td>

</tr>

</tbody></table>

</center></div>

</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

575

6.

576

To make this project even easier, click on the "A<img border="0" src="https://wiki.lynxmotion.com/info/wiki/lynxmotion/download/servo-erector-set-robots-kits/ses-v1-robots/ses-v1-bipeds/brat-biped-seq-b/WebHome/link.gif" >B"

577

button in the lower left corner. This screen allows you to link servos

578

together. Click on "Servo 1" on the left side and "Servo

579

17" on the right, then click "Add." Do the same with Servos

580

2 and 18. This will allow you to switch the positions of the right and

581

left legs with just a few clicks.</td>

Figure 6.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

592

7.

593

The first step in this walk is to get the robot into position to take a

594

stride in the second step. Set your servos to the degrees shown in Table

595

7. They don't have to be exact; close will do. When you're done, click on

596

the red "=" in the Step section to overwrite Step 1.

<td >

</tr>

<tr>

</tr>

<tr>

</tr>

</tbody></table>

</div></td>

</tr>

<tr>

Table 7.</td>

</tr>

</tbody></table>

</center></div>

</td>

Figure 7.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

642

8.

643

Now, click on "A<=>B" and deselect the "Selected

644

step" check box and click OK. Then click the green "+" in

645

the Step section to add the current position as a new step.</td>

Figure 8.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

654

9.

655

To shift the robot's weight, just use the sliders and switch the degrees

656

for Servos 0 and 16. Click on the green "+" in the Step section

657

when you're done to add this as a new step.</td>

Figure 9.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

667

10.

668

Now all you have to do is take another step! Click on the

669

"A<=>B" button again, deselect "Selected step"

670

if it isn't already, and click OK. Click on the green "+" in the

671

Step section when you're done.</td>

Figure 10.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

680

11.

681

To test the walk sequence, click on the sequence loop button on the right

682

side of the screen under "Play." You can stop or pause the

683

walking sequence from the Play menu.

684

If you were successful, the robot should

685

be walking now. If the robot doesn't walk in a straight line, try

686

increasing the ankle degrees so that more weight is shifted.

</td>

Figure 11.</td>

</tr>

<tr>

</tr>

<tr>

<td valign="top" align="left">Step

697

12.

698

To adjust the biped's walking speed, you can use the "Advanced

699

Play" feature. Click on the Advanced Play button on the right side of

the screen.</td>

Figure 12.</td>

</tr>

<tr>

</td>

</tr>

<tr>

<td valign="top" align="left">Step

711

13.

712

By moving the Time slider, you will adjust the speed of all the servos in

713

the project to a percentage of the normal speed. 100% is the project's

714

normal speed. Moving the slider below 100% causes the robot to move

715

faster, while above 100% slows the robot down.

716

Click on the Loop button to test your new

717

speed. You can tweak the speed while the robot is moving to get it

718

perfect.

719

If you click on the Apply button, the new

720

speed will be applied to the project. </td>

Figure 13.</td>

</tr>

</tbody></table>

</body>

Wiki source code of BRAT Biped SEQ Tutorial v1.06XE

Navigation

Recently Visited