First Mechanical Assembly Trial

In early February, once the machining was completed, we attempted to assemble the components to test if they were fabricated with sufficient precision and if the design overall is effective and produces the expected motion. Due to some unforeseen circumstances in the assembly of the components, the full motion of the mechanical assembly could not be tested. Some problems were found during the assembly. The first issue was that the telescoping tubes did not remain at the centre of each dowel and slid away from the centre. This caused interference when trying to pull the collars up and down. As well, the inner telescoping tube is much smaller than the outer telescoping tube, so when the legs are fully deployed and have force applied to them, the tubes do not remain collinear. To resolve these issues, 3D printed spacers are being created which will keep the legs centred on the dowels and the telescoping tubes centred and collinear with each other.

Some other issues that were found were related to the power screw guide L-block. Firstly, the wrong bushing was ordered, so the hole in the L-block and shaft were the wrong size. As well, the holes that attach the L-block to the collar lined up so that there was interference between the L-block, the shaft that goes through it, and the legs. To solve these issues, the L-block is being reprinted with the holes realigned in the correct orientation. As well, it was determined that the bushing was not necessary to achieve sliding motion. So, the hole in the L-block was resized to fit the shaft directly rather than making the block bigger to incorporate the bushing. Finally, we discovered that the power screw nut could not be attached properly to the L-block since the bolt holes that were created to attach it interfere with the collar below it. So, a plate will be created that bolts all the way through the collar to hold the nut in place instead.

Figure 1: Assembly Process Pictures