General Misc > Robot Videos

fun 4-legged robot

(1/3) > >>

Admin:
Its not very effective at walking, but its still really neat looking.

[youtube=425,350]JnfEyMRDUHk[/youtube]

I think that if it had rubber feat that it would work much better . . .

oelewapperke:
Looks simple enough to construct.

Seems like it's just 8 servo's attached in a pretty straightforward way.

This thing would benefit a lot from feedback loops instead of straight overpowering. Can you get a force measurement from servo's ? Ie. can a servo report how much resistence it is encountering ?

oelewapperke:
Is there any way to get a servo to report the resistance it's encountering ?

If I remember my motors class you basically measure how much juice the engine is sucking up, but does anyone have an idea how to do it ?

dunk:
i don't know how accurate it would be but you would get some idea by measuring the current the servo is drawing.
it would be difficult to determine the difference between a moving servo horn and a stationary servo horn under pressure.

maybe if you combine readings from an encoder on the servo and current draw....

dunk.

JonHylands:
This (the issue mentioned by dunk) is actually a pretty big deal. The AX-12 servo (part of the Bioloid robot kit) has this type of measurement, and you can't tell whether the current draw is due to external forces on the servo, or just the current draw of the motor as the servo is moving, or both.

Series elastic actuators actually solve this problem nicely - the force measurement is independent of the motor current, so it is always measuring the external force.

- Jon

Navigation

[0] Message Index

[#] Next page