As we overhauled our initial vertical clamping method, we had to rethink all the clamps (gg so much effort).
However, with our collective genius (!!!), we managed to create 3 new clamps using toggle clamps and some 3D printed parts. In the creation of these 3 new clamps, we definitely kept some crucial concepts in mind:
- Secure the stability of the unit with the maximum number of points of contact to stabilize the unit in a 3D space. The unit will likely be rotated 270 degrees about its longest axis and may be subject to some rotation about its short axis across the unit, perpendicular to the unit, due to the rotation of the long unit to fit through the train door.
- Do not cross the top most bunch of wires as this will cause our clamps to hit the roof of the working space.
- Clamps must be able to be slid in from the base of the unit without requiring vertical motion. This will enable us to better unclamp and slide our the unit in the working space.
- Clamps used are restricted to toggle and push clamp connected to aluminum profiles directly or via brackets
- Power supply housing and wires should be avoided and not directly clamped. Too much force should not be exerted on these sensitive electrical components as they may be damaged.
Here is what we have done so far:
From right to left, Clamp 1 and Clamp 2 are pictured below:
As can be seen, Clamp 1 has 2 points of contact. Using the current pictured orientation of the unit as our reference, clamp 1 will prevent motion upwards and towards us.
Similarly, Clamp 2 has 3 points of contact. Using the current pictured orientation of the unit as our reference, clamp 2 will prevent motion upwards, towards us and to the right.
Clamp 3 is pictured below and it has 3 points of contact too. 2 points of contact to prevent the unit from moving towards us and 1 to prevent the unit from moving downwards.
There is a direct relationship between the points of contact and the stability of the unit when being lifted. Hence, we are aiming to have at least 10 points of contact for clamps in total when the whole clamping system is done. Since there are already 8 points of contact with these 3 clamps to the right of the CG of the unit, our progress with the clamps seems very promising!!
Also, we made progress with solidworks. We created a holder for the long L-shape metal tubing, to be coupled with a clamp.
We first thought of this design below, but realised it was not the best idea to approach and clamp the metal tubing from the top, since we want to avoid any kind of clamping from the top as much as possible given the limited vertical clearance.
Furthermore, it would also not be able to prevent any downward vertical movement of the metal tubing (away from the grip), which makes the unit more prone to becoming loose from this grip.
A much better idea was to clamp the metal tubing from the side using a rotatable aluminium profile. (Please note that the photos were taken from 2nd July’s post, purely for illustration purposes of why we chose this design. On 1st July, we had not yet printed this grip.)
This is how the locked red 3d grip would look like after the profile was rotated clockwise (using an appropriate clamp). This way, the metal tubing cannot drop loose in the downward vertical direction (unlike the previous design). The only can it can become loose out of the groove is if it moves horizontally to the right. Thus, we settled with this second design.
This design will be subject to some adjustments, but the addition of this grip will increase in the number of points of contact for the unit, which is, of course, good news.
Also, we 3D printed and refined the design of the ball joint holder”
Here are our 2 ball joints on top of 3 2020 aluminium profiles. This will make up our double ball joint configuration in between our third arm and clamping system for great adjustability of the clamping system. It works by allowing the ball joints on each side to rotate individually. The combined rotation of the 2 ball joints will allow the whole double ball joint configuration to be especially adjustable.
