Hexapod Question
I built a hexapod and I was going through the initial setup an noticed a couple of anomalies and wondered if this was normal or not. I'm "driving" the servos directly from a BS2: servo power is provided by a separate source.· Currently I'm going through each servo to determine,"min", "mid", and "max" value for each.· The first anomaly is servo "humming". With the hexapod supported I noticed that no matter what value I give a servo some of them hum when they reach the position giving by the BS2. I using a For/Next program with the pin going to "input" once the position has been reached.· Is the humming normal or does it signify something else?· The second anomaly is after I determined the above values, I commanded the legs into the "standing" position and placed the hexapod on a surface to see if it was "level".· When I changed a value on one servo and "ran" the program, the servos would cycle even though I wasn't changing·other values. I thought that maybe when the program began, that there was a brief moment that the servos were not receiving a signal, and the weight of the pod was "back-driving" the servo, but I can extend the legs, shut the power off, and it remains standing.· What is causing this?· Any programming tips would be helpful.
Thanks
Brian
Thanks
Brian
Comments
RC servos are designed to constantly receive pulses on their signal lead.
When you make the driving stamp pin an input, the servo signal lead is
floating open, susceptible to noise pickup, whatever. I don't know what the
servos will do in this condition. I believe this is one reason that people
use the Al Williams servo board which constantly pulses the servos.
Ray McArthur
Original Message
From: Brian & Sandy McMillion <brianmcm@w...>
To: Stamps Forum <basicstamps@egroups.com>
Sent: Saturday, January 20, 2001 6:40 PM
Subject: [noparse][[/noparse]basicstamps] Hexapod Question
I built a hexapod and I was going through the initial setup an noticed a
couple of anomalies and wondered if this was normal or not. I'm "driving"
the servos directly from a BS2: servo power is provided by a separate
source. Currently I'm going through each servo to determine,"min", "mid",
and "max" value for each. The first anomaly is servo "humming". With the
hexapod supported I noticed that no matter what value I give a servo some of
them hum when they reach the position giving by the BS2. I using a For/Next
program with the pin going to "input" once the position has been reached.
Is the humming normal or does it signify something else? The second anomaly
is after I determined the above values, I commanded the legs into the
"standing" position and placed the hexapod on a surface to see if it was
"level". When I changed a value on one servo and "ran" the program, the
servos would cycle even though I wasn't changing other values. I thought
that maybe when the program began, that there was a brief moment that the
servos were not receiving a signal, and the weight of the pod was
"back-driving" the servo, but I can extend the legs, shut the power off, and
it remains standing. What is causing this? Any programming tips would be
helpful.
Thanks
Brian