🚀 go-pugleaf

>In article <1990Aug30.014817.8794@portia.Stanford.EDU> boehlke@sunrise.stanford.edu (Dan Boehlke) writes:
>
>   I see the next breakthrough in robotics being the 
>   introduction of very high accuracy manipulators--
>   say an order of magnitude (or more) better than
>   any systems of the 80's.  There are plenty of potential
>   products that simply cannot be assembled today anywhere 
>   outside of a laboratory.
>
>Very high accuracy manipulators are very difficult to design using
>today's technologies if they are to be of any general use.  The best
>(gp commercial) figures I remember from the 80's are approx. .001"
>repeatabilty for a _light duty_ electronic assembly robot (working
>envelope ~ 1 cubic foot).  

One reason humans are capable of high accuracy tasks (putting a chip
on a circuit board for example) using a low accuracy manipulator
(the human arm) is because of the use of end point control.  One looks
at what one is doing while doing it.  Instead of making a robot more accurate, 
the loop needs to be closed at the end point using either vision or other
sensors.  Then only the resolution of the robot is important which of course
is much simpler than improving the accuracy of a manipulator.

End point control is also advantageous because it can eliminate the 
need for special linear slide joints, a temperature controlled environment, 
an isolating granite slab, and frequent recalibration.

Mike Smith
HP Labs