Question

Do they make more or less noise then a standard servo?

Thanks

I haven't heard anything about these servos - but you mention they're FeeTech compatible. You're experiencing an issue where the position cannot be read?

Maybe before we recreate the wheel if they're compatible, let's look at how you're connecting them and what kind of EZB is being used. This way, we can identify any potential connection issues that is preventing bi-directional communication. So, can you tell me these things..

1. What kind of EZB are you using?

2. Do you have the WaveShare signal-line connected to both the hardware RX & TX of the EZB? Remember, this must be using HARDWARE UART, not software uart on the EZB. So what ever EZB you are using, it must support hardware uart for bi-directional communication.

3. Do you receive any errors or log messages in the feetech robot skill console window?

4. Anything else you can think of adding or telling me so we can identify if it's a connection issue before allocating resources to develop a robot skill.

Update / Feedback to serial wave share servos.

@Mr Ball, the servos do not produce any noise even under high load and run smoothly to their target position via an acceleration and braking curve.

The servos of the ST-series (e.g. ST3025 or ST3215) can be addressed directly with Skill Feetech RS 485. The servos can be addressed by both the Waveshare and the Feetech UART controller. WS servos of the type SC-series (e.g. SC15) can be addressed via skill Feetech serial bus servos

There are two restrictions:

1. Speed can only be controlled via Acceleration. Values between 1 and 20 make sense. Speed and velocity values have no effect.
2. No positions can be read back. That's a shame, but it's probably due to the COM-xx connection. Here ARC indicates a connection error.

I now operate 28 ST-servos in my humaniod pib-robot and I am satisfied. Although position feedback would be great.

Robochess, I read your comment about speed and made me think. So I checked your diagnostic log and you’re running ARC Free but you’re a Pro user

Upgrade to ARC Pro to experience pro features.

Hi DJ Sures,

I already have a Pro annual license for two PCs. There seems to be something wrong with the diagnostic log, or it's because I sent my last post from a PC that actually only had a free version installed. If that was the cause, things should be different now. A Pro version is installed on this PC (my Robo-Labtop).

Okay perfect - can you answer these questions for me...

1. What kind of EZB are you using?

2. Do you have the WaveShare signal line connected to both the hardware RX & TX of the EZB? Remember, this must use HARDWARE UART, not software uart on the EZB. So what ever EZB you are using, it must support hardware uart for bi-directional communication.

3. Do you receive any errors or log messages in the feetech robot skill console window?

4. Is there anything else you can think of adding or telling me so we can identify if it's a connection issue before allocating resources to develop a robot skill?

I use a WS Serial Bus servo Driver Board and operate it directly via a USB C interface. In my case it reports via COM-17 via WIN. ARC cannot initially establish a connection to the port.

The error message is -Port Connectin Error-.

In the Feetech RS 485 Skill, at least the TX communication works weel and the servos can be addressed as described. Message from the Feetech skill is COM17 @ 1000000bps.

If it is better to use a PI, Arduino or ez-b v4, for example, I am free to do so. Everything is there so far.

Link: WaveShare servo Driver Board. https://www.waveshare.com/wiki/Bus_Servo_Adapter_(A)

Okay, if you can answer these questions, please.

1. Do you have the WaveShare signal line connected to both the hardware RX & TX of the EZB?

2. Also, RS485 robot skill seems to use different commands than the SerialBus robot skill. Can you verify that the SerialBus robot skill works for moving the servos?

Hi DJ Sures,  thank you very much for your support!!

To the questions.

1. So far I have not used the discrete UART connections TX and RX, but rather connected the servo controller to the PC via USB.

I then tested the connection using the Python and Arduino programs provided by WaveShare. Both work well, even bidirectionally. The servo data such as position, temperature, etc. are sent and received. So far it looked good, even the connection in both dirictions.

2. I tested the Feetech serial bus skill firsst. I assumed that this was the right skill. It only works with the WS servo series SC15 but I use servos from the ST series. Although these servos move with the Feetech serial bus skill, but the positioning is completely wrong. With the Feetech RS 485 skill, they run as they should. But without position feedback

No data is received from the servos in either skill