Wheel Molding

Two wheel molds were machined out of the UHMWPE. The roughing & finishing sequences used in Pro/MANUFACTURE left a nice inner finish, so hopefully the finish on the outside of the wheels once cast will be similarly good.

Vahid made an excellent suggestion of using a vacuum-packer to ensure that air bubbles are minimised during casting. Depending on the cost, one will be purchased during the weekend.

Rear Assembly

Machining the rear section was completed this afternoon. As can be seen from the photograph, the rear section (that mates with the entire assembly) has been assembled & bolted into place. Beneath are the swivel mounts (with bearings press-fitted in) that will mount onto the rear & locate the rear hitch.

Hopefully by the end of the week the entire rear assembly wil be complete. Once assembled, testing of the platform can begin, with the drive mounts fully assembled and secured.

The final act of today was to set up the mill ready to machine the casting blocks for the wheels. If this is completed, casting of the wheels could be performed on the weekend.

Chassis Completion

As can be seen from the neighbouring photographs, the main chassis of the robot was machined and assembled. Unfortunately, the white UHMWPE does not appreciate being handled, and the rig has now taken on a smidged-white look,

Fortunately, as this is just the test platform, this will be remedied in the final design. As mentioned previously, the new colour scheme will be a black body & yellow perspex canopy.

In addition, a few software programs were downloaded from the 'net that streamed DGPS correctional data from Califonia in the US. Although useless for our purposes, it shows the application of a dedicated web-based DGPS server is viable.

DGPS Research

Research has been proceeding as to the implementation of a DGPS web-based server here at UCT. A machine (currently the one that hosts this blog) is available for use in the development of the server. The capabilities of the machine may be an issue, however according to research on the web, a client requesting DGPS correction requires a data transfer rate of only 50 bytes/sec, as opposed to a typical internet radio station (500 kb/sec), so if performance is seriously compromised, the an upgrade may be required.