Design Issues

4/13/95

The following lists are an attempt to carefully document all outstanding issues in this project. Please send mail to Carolyn Valiquette (cvalique@cs.utah.edu) if you have anything to add.

Items that need to be mounted in the seeker tube:

Amp/rate sensor board (Board 1)
4.5" x 7.5"
Mounted horizontally in center of missile tube.
"One idea is to create a pair of plastic card guides that spans the length of the composite tube and is fastened to the two metal rings at each end of the tube. If we are able to secure the amp-rate board with these card guides, the attached PSD-electronics board (and it's piggy-back controller board) will stay put as well." - from George Toye's notes.
PSD analog circuit board (Board 2)
4.0" x 7.5" x 0.062" +/- 0.002"
Mounted "below" first board with 1/2" stand-off mountings holding the two together.
CPU/Controller Board (Board 3)
Dimensions?
Connected to Board 2.
Heat sinks (2)
3.30" wide x 2.30" long
Mounted to the top of the 2 amps.
1/8" clearance to seeker tube.
This is actually a larger area than recommended in the amp catalog (5.00" x 3.62").

Fan
1.58" x 1.58" x 0.41"
Mounted to a plate "below" board 3.
Plate for mounting fan
Size?

Other items that we need to consider:

Box for control interface
Description?
Stationary connectors for PSD wires
Size?
Mounted to back of primary mirror.
Stationary connectors for hall effect wires
Size?
Mounted to ?

4/5/95

The following figures are intended to clarify the placement of the magnets on the magnetic keeper disk. The configuration shown has approximately a 90 degree separation between the magnets. The maximum inset depth of the magnets should not exceed 1/2 the thickness of the magnets (1/32 inch).

Since we have to redesign the keeper and placement of the hall-effect sensor, there are a number of questions:

Is there a minimum thickness of the magnetic keeper material that must be left "under" the magnets?
Could the same keeper disks be used that already have the holes in them, placing the inset magnets on the opposite side of center? Would holes on the other side of the disk effect the field?
Could we make the keeper with three pockets, one for a "permanent" magnet, one 90 degrees from that, the third 105 degrees from the first? Would the second and third pockets overlap? If so, would that that disrupt the magnetic field?

2/16/95

A design meeting was held at Utah on Februray 16, 1995. Click here to read the notes from that meeting.

1/24/95

The gimbal assembly page has been updated to iclude seeker base information.

Prior to 1/24/94

The primary and secondary mirror, optical spider, shade, and rate sensor mounts have all been manufactured. The gimbal ring will be manufactured next.

The mirrors were hand polished, nickel plated, hand polished again, and will now be sent for gold plating.

The payload ring, or inner gimbal was removed from the design, thus reducing the number of manufactured parts. The primary mirror is now the inner gimbal.

The bearing/encoder caps are now two different sizes due to the difference in size of the motors and encoders.

The missle body shell has been added to several of the images. The axis from the lower right to the upper left of the images above is mounted to the missle body shell via the bearing/encoder caps. The shape of the outer surface of these caps has been changed to fit smoothly with the missle body shell. This eliminates the need for a plastic fairing which would have been mounted to the bearing caps. This eliminates a part (the fairing) and the problem of how to fasten it.

The composite casing, manufactured at the Michigan State University Composites Center will be mounted to the bottom of the missle body shell with the help of an adapter ring. The mold for the casing was manufactured here at Utah and sent to MSU.

Both the bearing and the encoder caps are smaller because #2 screws will be used for mounting them, rather than #4.

Carolyn M. Valiquette
cvalique@cs.utah.edu