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Feetech Serial Bus Servo

Control Feetech serial bus servos from UART or PC COM port.

+ How To Add This Control To Your Project (Click to Expand)
  1. Make sure you have the latest version of ARC installed.
  2. Select the Get button in this page to download the archive file.
  3. Double click the downloaded archive file to execute installer.
  4. The installer will add this control to ARC.
  5. Load ARC and press the Project -> Add Control button from the menu.
  6. Choose the Servo category tab.
  7. Press the Feetech Serial Bus Servo icon to add the control to your project.

Manual

Control Feetech serial bus servos over EZB UART or PC COM port. The selected ARC’s Vx virtual ports must match the servo IDs in the config scree  - and voila, you're off to the robot races!

Main Window
The main window on the project workspace will display information about active connection and errors. To configure the servos, press the ... configuration in the title bar.
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Configuration Screen
The configuration allows selecting the virtual servo ports that represent the ID's of the Freetech servos. For example, if the servo ID is #1, then V1 will be used. Also, the communication type must be specified (EZB UART or PC COM Port). 


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Baudrate
The baud rate of this skill is 1,000,000 bps, which is also the default baud rate for Feetech servos.

ID
All new Feetech servos will have a factory default ID of #1, which is V1 in ARC. If you want to reprogram the servo ID, you need use the SCS15 software V1.6. from here. The software requires connecting the servo to either their USB device or using an Arduino. The Freetech website contains more information. 

How To Use
These steps will demonstrate how to add the Feetech serial bus skill to a project and use a standard servo skill control to move it. All skill controls that use servos will now be able to move the servo. This includes camera, joystick, scripting, and more. Simply select the virtual servo port and any skill will be able to move the servo.

In this example, we'll be using a USB Feetech servo controller. These controllers will create a COM port on the PC that we will select. The SCPC-2 or URT-1 work great for this application. Alternatively, if you wish to wire the servos directly to a custom hardware UART, it will require the option to be selected in the config menu in the steps below and additional hardware. 

Step 1
Load the latest version of ARC on your Windows based PC.

Step 2
In ARC, press Project -> Robot Skills -> Add from the top menu
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Step 3
When the skills window is displayed, select Servos and locate the Feetech Serial Bus skill. Press the Download icon to download and install the skill to your project.
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Step 4
Locate the Feetech Serial Bus skill on your project workspace. Press the Config button in the title bar to access the configuration menu.
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Step 5
We will be using the USB COM Port to control the servos in this example. Select the Use COM Port option and select the COM port for the USB controller.

Additionally, the default ID of a new servo will be #1, which is V1 in ARC. A servo ID of #2 will be V2 in ARC, and so on. Select the V1 so ARC will now map all references of servo V1 to the Feetech servo with ID #1.

Press SAVE
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Step 6
Now we will add a basic servo control to test the Feetech servo. Press Project -> Robot Skills -> Add from the top menu. Locate the Servo tab and click the Horizontal Servo to add it to the workspace.
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Step 7
Configure the Horizontal Servo skill by pressing the config button in the title bar
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Step 8
Selecting the port for this control. Press the Port button to select the servo port.
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Step 9
The dialog popup for port selection will display. Select V1 from the Virtual Port drop down list. Press SAVE
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Step 10
The Min and Max range for the servo can be selected. Each control that uses servos will have its own custom range. Click in the Min and Max value and drag the mouse UP or DOWN to select the range. Or, alternatively you may right click to enter a range with the keyboard. Keep in mind, the servo will move into each range as you change the value. Press SAVE once the range has been adjusted to return to the workspace.
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Finished
You may now click on the servo value to drag the mouse Left or Right to move the position. If you right click, a numeric value can be entered by the keyboard. The servo will only move within the range you specify.

Try other robot skill controls, such as the Auto Position or Joystick with this servo. All robot skills that use servos can now reference this servo by the virtual port ID. 

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PRO
USA
#16  
Ok cool. They are sending me out a box of stuff. I hope the protocol matches and is the same throughout their product line.
PRO
USA
#18  
From their PDF  -  Protocol Type: Half duplex Asynchronous Serial Communication!
PRO
USA
#20  
Well darn. Ok I'm off to vacation. Prolly be waiting for me when I get back. Find out then...suspense!
PRO
USA
#21  
Ok I've found this on a data sheet..saying that the three types of servos all use the same protocol. So this particular model uses 12 volts and has 4 wires. I assume the "A and B"  are tx and rx? Here is a pic.

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PRO
Synthiam
#22  
No - you’ll need to use a usb adapter or something. You can’t connect the servos directly. See our conversation thread above.
PRO
USA
#23   — Edited
I hate my brain rot.....this isn't going to work...(throws in trash)...sighs...we need powerful, quiet, affordable ($50 to $125 ) actuators that are at least 80 to 120 kg/cm, that work with TTL or PWM...otherwise, there will be no cool full-sized robots in the future...
#25  
Yes, I'm also curious. Looks like you have the power and affordability. are they too noisy?
PRO
USA
#26   — Edited
@dave , yeah much louder than I thought it would be.

@DJ, The Rs-485 servos come with a factory default of 115,200 not 1000000, but easy to change in the software.
PRO
USA
#27  
Ok I have the motor running..but its just moving erratically. It moves full CW direction and then full CCW direction...when I move servo slider. 

#29  
Have you tried running it at the factory default of 115,200? Just a shot in the dark from me.
PRO
USA
#30   — Edited

Quote:

Baudrate
The baud rate of this skill is 1,000,000 bps, which is also the default baud rate for Feetech servos.
Unfortunately, I am unaware of a way to change the baud rate within this plug in.  But I used my servo with Feetechs software and everything worked as expected out of the box, with no problems (both 115200 and 1000000). So def some kinda issue with how these servos work compared to the TTL servos, even tho they say these use the same protocol.
PRO
Synthiam
#31  
What ttl servos are you using that work fine? Are you saying some of their servos work and some don’t?
PRO
USA
#32   — Edited
I am assuming this skill was created to use the TTL versions of their servos the SCS and the STS series. I do not have the TTL servos. So I cannot say if they work or do not work with this skill. I assume a TTL servo was tested when the skill was created.

I have the RS-485 version and I am using the URT-1. See the above video.
I have also included the protocol of this servo in post #28
PRO
Synthiam
#33  
Not a clue. I know it uses the SCPC-2 or URT-1. So If those are ttl then it’s ttl. Those adapter boards are mentioned in the manual for the skill. 

the protocol used is what they would have given us to have the robot skill created. 

i might have a few minutes to look at the protocol doc you sent and see if it’s different. Who knows - hardware companies do strange things....
PRO
Synthiam
#34  
That protocol is entirely different. It's crazy how they'd change that much. I have no way to test it but I can publish something. No idea if it will work because their documentation is incredibly poor.