Hello,

I am a newb to this forum and am asking for some help.

My son is building a robotic hand for a science project using IC circuitry and servos. He wants each finger to open up sequentially, stay opened until the last finger is opened, close sequentially, then start the process all over again. I can easily build a 555 as an astable multivibrator to produce the clock pulse, but I can't come up with the second part of the circuit that will keep a pulse high for a set time. Would a 4066 be able to do this?

Any help would be greatly appreciated!

Thank you.

Howard in Elvis' World

 

One method might be to use a 4017 Johnson counter and diode-OR the inputs to the "digit" drivers. The 4017 has 10 outputs that are high one at a time, starting (reset) with all low.
So,
Reset
Output 0 would go to the thumb
Output 1 would go to the thumb, 1st finger
Output 2 would go to the thumb, 1st finger, 2nd finger,
Output 3 would go to the thumb, 1st finger, 2nd finger,3rd finger
Output 4 would go to the thumb, 1st finger, 2nd finger,3rd finger, 4th finger
Output 5 would go to the thumb, 1st finger, 2nd finger,3rd finger
Output 6 would go to the thumb, 1st finger, 2nd finger,
Output 7 would go to the thumb, 1st finger
Output 8 would go to the thumb
Output 9 no where

Ken

 

Ken,

Way too simple! Thank you!

Howard

 

Are you familiar with diode-ORing? Can you post a schematic or diagram of what you have so far. I hate steering someone in the wrong direction because I didn't understand their whole setup.

ken