Saturday, March 9, 2013

Neck Design Update

Here's an quick look at the neck design...

This is more of a proof of concept but I'm trying to see if the current dimensions will work with either fabricated parts or off the shelf parts. The internal linkages were designed with readily available parts but the outer shell dimensions will have to change such that I can either make them or use some sort of common PVC pipe sizes.

The internal mechanism for the lower neck is still missing an adjustable idler pulley as a tensioner but besides that, it is good to go. As for the upper neck, I still need to add a shaft mount for the rod to attach to the upper neck somehow. In addition, I still need to design the head swivel mechanism which will be powered by a servo.

The bottom of the linkage in the lower neck will connect to a stepper or gearmotor via a rod end but that doesn't seem too difficult at the moment.

Like I said earlier, I still need to check the dimensions for accuracy as well so that will take some time.

Edit: So, the original design was to use a parallelogram linkage to keep the upper neck aligned with the horizon, but I decided to change it and scrap the parallelogram linkages altogether. Instead, I will be use an aluminum bar instead.

This allows it to be much simpler with less pieces and accomplishes the same thing. The only addition I will be doing to these side linkages will be to cut some slots and holes to reduce the weight. Also, the two bars that hold the last part at the top will probably be changed to be more rigid.

I don't know why I was trying so hard with the other design... let's try to keep things simple!

Edit2: Final edit before I go to sleep.

I finally found an idler pulley with the right size! I had to go to a metric idler used in the Shapeoko but it'll work. Anyways, the position of the idler pulley is tentative for now. I will have to see what lengths are available and adjust the location of the idler pulley accordingly. There should be enough room up and down to give it some tension but if not, I will have to add a second idler next to it. Alright, time to sleep...

No comments:

Post a Comment