RGB Motion Lights

[jerrymac]

DAN great job. how about a full how to ?

[crackchecker]

Thanks Jeff,

Would love to see the lights swing back and fourth but return to the center, or 50% when done doing the swing sequence. even if the lights are still on.



Jeff Millard wrote:

crackchecker wrote:

Question for you Dan. The servo suppliers site doesn't mention if they go back to zero position when you stop or if they stay in place. I can see posibilities if they return to a zero position.

The final resting position of analog servos is based on how you sequence them, and if you choose to use the "All Off" command at the end of a sequence. If you don't use the All Off command, the servo will rest in a position based on the last percentage it recieves at the end of a sequence. Otherwise, it follows the percentage existing in it's assigned channel. If that channel is at 0% the servo will be at the full counter clockwise. if it's at 50% it will be at it's mid point. 100% will be full clockwise. If the All Off is selected in the show plaer and sequencer, the servo will always drive to full counter clockwise at the end of a sequence.

Jeff

[Dan C]

Thanks for the explination Jeff. If you want the lights to return to 50% when done swinging, simply change the percentage to 50% when you want it to change.

On that note. When you sequence the servo dog. Almost every cell needs to have something in it. I start by setting all the channels to 50% intensity for the entire sequence. Then when I want a servo to move to a particular position, (lets say full left). then I simply change those cells to 100% on. then full right would be 0% or off. if I want the servo to only move half way left or right I set it at 25% or 75%. If I want a slower transition. I do a fade between two intensity values. Hope that makes sense.

Also something to note. Servo speeds are based on a couple things. Some servos are rated to travel faster from lock to lock, others are rated slower but have more torque.

For my servos here are the specs. (HS-485HB)
Range = 180°
Voltage = 4.8 - 6.0vdc
Torque = 83 oz.-in.
Weight = 1.59 oz.
Speed = 0.22s, 0.18s / 60 degrees

What this means is for every 60 deg or movement it takes .22 seconds and .18 seconds at 4.8 volts or 6 volts respectivly.
So if you want to go a full 180 deg. Full left to full right it takes .54 seconds at 6 volts. or .66 seconds at 4.8 volts. Please take that into account when you sequence. you can't have a servo move full left/right every tenth of a second. If I want a light to start out at full left before the light turns on, I set the intensity at least .25 seconds before the light turns on so that the servo has time to move to its proper position. Understand?

You would be best to get a servo that has a fast speed since you don't really need a lot of torque to move these little lights. It depends on your situation though. Also, you can increase that speeed and torque by upping the voltage, however most servos run at 4.8, 6 or even 7.5 volts. I have personally never run them more than 6.5 volts. Again you would need to see what the servo was rated for.

[paulanator]

Dan,
your project really rocks.

Also, thank you for your details on programming the servos.

I am working some animation with servos and the details on sequencing the channel at 50%, and the timings really helps me to get started on my project.

Thanks!