No servo movement , servo getting hot.

Forums:

Hi I've just received my ultraborg and wired it up as per instructions. I'm using a battborg to power the ultraborg. I have 1 no name brand servo attached. I've used the GUI and run the sequence but I get no movement from the servo it just gets warm. Any ideas ?

Cheers
John

piborg's picture

The first thing to check is that the servo is connected the correct way arround.
If it is connected the wrong way it will be constantly trying to move beyond the limit of the servo.
The connections as marked on the board are:
- - 0V, also known as Ground.
+ - 5V, also known as Power.
S - Signal, also known as Control or Position.

If it is connected correctly try to see if you can move it with the servo tuning GUI.
If you can it probably just means that the deafult range for this servo is not very standard.
In this case setting the correct upper and lower limits should make the servo work correctly.

Thanks , I've rechecked all connections. I swapped the servo for a Fatuba S3003 tried the GUI and run the sequence still no joy. Here is a copy of the terminal log

Loading UltraBorg on bus 1, address 36
Found UltraBorg at 36
UltraBorg loaded on bus 1
Press CTRL+C to finish
Move to central
Sweep to start position
Sweep all servos through the range
Failed sending servo output #1!
Failed sending servo output #1!
Failed sending servo output #1!
Failed sending servo output #3!
Failed sending servo output #3!
Failed sending servo output #1!
Failed sending servo output #3!
Failed sending servo output #1!
Failed sending servo output #3!
Failed sending servo output #3!
Failed sending servo output #1!
Failed sending servo output #3!
Failed sending servo output #3!
Failed sending servo output #3!

Where do I go from here?

piborg's picture

It could be that the servos are not able to get enough power.

  1. Is the 5V link jumper fitted?
  2. Do you have power attached to the V+ and GND screw terminals?
    If so what batteries / supply is attached?

Hi, no the link is not connected, I thought this was only for the ultrasonics ? I'm using a 20v li-ion battery pack via a battborg which is supplying 4.9v to the ultraborg.

piborg's picture

If there is no supply connected to the V+ and GND screw terminals then you will need to fit the 5V link to use the 5V supplied to the Raspberry Pi.

My Battborg was connected to the V+ and GND of the ultraborg with no link. I've disconnected the Battborg and reconnected the link .....no movement and the servo heats up. I'm really at my wits end.

piborg's picture

If you could take a photo or two of how the servo and power are all connected that would help us solve your problem :)

Please find attached photo's of my ultraborg, hope this helps.

Images: 
piborg's picture

That is great, thanks :)

Could you also attach some photos of:

  1. How the Raspberry Pi is connected
  2. The servo connections themelves
  3. The battery connections

Photos as requested

Images: 
piborg's picture

That was not quite what I was after :)

What I am trying to see is:

  1. The full run of the cables between the UltraBorg and Raspberry Pi
  2. The full run of the wires from the servo to the UltraBorg
  3. The full run of the battery connections from the battery itself to the UltraBorg
Subscribe to Comments for "No servo movement , servo getting hot."