Computer Control of the Dome

Over the past few posts I’ve been using the expression “We have done XYZ” a lot rather than “I have done XYZ”, which as any PhD supervisor knows probably really means “My student has done XYZ” at least to some degree.  In this case to a very large degree the vast majority of the ongoing work in the dome has been carried out my my second student intern Sunayana Bhargarva, who has been working for twice as long as Edo officially did. Unfortunately we haven’t had too much in the form of pictures or videos of her to put up here (careful readers will have spotted her in some videos).  Mark my words however the greatest effort and momentum over the past two months in this project has come from her.

She has been trying to get the dome to rotate 100% reliably, we are not there yet but we are on the way:-

In the early stages of getting the dome to rotate via the motors, after prolonged use, the cogs would start to disengage with the timing belt, generating horrendous noise and no rotation. This was, in part, due to the cylindrical structure of the motor, causing it to slip on the wooden shelf and no longer maintain the angle needed to grip the belt.
This problem was attacked by Sunayana using some high grade emery paper, slotted under the bottom of the motor and inside the necessary jubilee clips (anyone know why they are called that?), to provide enough friction and control against any unwanted rolling or slipping. Additionally, wedges were placed underneath the wooden hinges supporting the motors to achieve maximum contact between the cogs and the belt. As the motor shelves are tightened in their positions, the contact is most strong along the bottom half of the cog. However, by reinforcing the wooden hinges with wedges, the entire system is pushed up slightly, allowing the top of the cog to also make continuous contact with the timing belt, making rotation smoother and less prone to jarring.

So that’s pretty nasty messy frustrating stuff.  Something more satisfying is what else she has been doing and that is getting the whole dome to rotate from a computer, which has involved a complicated set of relays, but which she has got working now.  I’ll let her explain:-

Now that the computer can move the dome, we hope to get the dome to track the telecsope automatically, but we’ll show you when we get that to work.

You should probably also know that Sunayana is quite an accomplished musician and successful poet, here she is reading one of her poems:-

 

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