Dagu 2dof Robot arm question

Community General Discussions
1

I bought this dagu 2dof arm recently

http://robosavvy.com/store/product_info.php/products_id/1594?osCsid=7ed23d473b22d4db12b8d1ecca353a39

I've wired everything up and it seems to work ok, however the servo that controls the gripper seems to get very hot, even when the gripper is open. I've been switching it off after a minute or so as i don't want to damage it.

Has anyone else here used one of these? Is it normal that the gripper servo gets so hot?

I found an instruction manual for the 6dof arm on the dagu support site  which seems to use the same gripper

https://sites.google.com/site/daguproducts/home/instruction-manuals

The manual seems to indicate that if the pwm pulse high time is outside of the range 660-1300 then the servo will get very hot.

On my gripper if i use a pulse high time of around 900, the gripper seems to be fully open, but the servo still gets really hot.

A pulse of around 2100 seems to almost fully close the gripper, but the servo gets even hotter.

Does this sound right ?

Any help or advice would be greatly appreciated

2

Thanks for the quick reply

Thanks for the quick reply :slight_smile:

Do you have any idea roughly what range of pwm pulse values i should be using? If i have a rough idea then i can experiment from there.

It seems that no matter what values i try the servo heats up really fast. For example if i set the pulse high time to around 1100, the gripper is not quite fully open, but the servo still gets really hot. Likewise if it’s fully open or closed.

3

dagu servos

If you’re using the small dagu miniature servos, then I have noticed this also…but not to extremes…I can adjust the pulse and it seems ok, but the problem I’m having is a constant chatter. I’m driving the servo from a 555 timer with a great square wave…about 80 to 90 hz and standard pwm settings (1.5 ms center)…the same circuit works well on my GWS servos, but continue to chatter on the Dagu…any info?