We're a few hours into the assembly process now, and have made a few mistakes of our own devising. Last night (Monday) wehad to go back and retrace some steps. Nothing serious - mainly the result of trying to do the assembly late in the evening after a long day at the office.
The good news is that our mistakes have been very easy to discover by comparing our work to the detailed exploded views in the robot's assembly manual. The worst case, which was actually pretty minor, involved disassembly back a few steps in the process and then putting the parts back together the correct way around.
As we reported in the last Project M post, by very late Sunday evening, we had successfully (we thought) assembled the robot's two arms, shoulders, head and power switch mounting bracket, plus the two feet/sole units.
The instructions are excellent and easy to follow - assuming that you're not too tired and sleepy. In reviewing our work last night it became obvious that we needed to pay closer attention to detail.
For example, the MANOI AT01 robot uses molded plastic frame parts that snap together very much like a 3-D puzzle. This provides mechanical stability and rigidity that's a big improvement over the flexing prevalent in designs that use softer aluminum frames that depend on bent angles and screws for stability.
When the upper bracket in this image is inserted into the mating bracket it literally 'snaps' into place and is mechanically locked. It's a tight fit, but can be disassembled by gently but firmly wiggling the two mating parts while applying a little upwards pressure to separate them.
In our hurry and excitement to complete the assembly, we managed to overlook the fact that the instructions call for a screw to lock the mated joint at this point in the process.
It's easy to see at the far left in this illustration, and of course there are notes in the manual about inserting the screws. But at the time we were totally focused on applying a little grease (supplied as a part of the kit) to the bushing on the other side and securing it in place. We must have been pretty tired, because the same mistake was made pretty consistently and had to be corrected last night.
All things considered, we're very glad that it was discovered at this stage. It would have been extremely embarrassing to have one of the limbs suddenly detach itself while showing off our new robot to friends.
We've been trying to take a lot of photos and some video of the process, though who knows when we'll have the time to sort through and do something constructive with them. The raw video clip below is a good example. It was taken on Sunday afternoon, right after the robot arm units were completed.
As a test, and to get some hands on experience with the robots RCB-3 controller and software, the hand (wrist?) servos were connected to the controller. A very simple and straight-forward program was quickly hacked together on the spot.
Four positions were created and then connected in an endless loop. You can't get much more basic than that.
Then, by double clicking on the each of the positions (POS1, POS2, ...) in turn, the desired servo positions were set. For purposes of this test the servos were connected to channels 1 (CH1) and 2 (CH2). The program moves the wrist servos first in-phase and then out-of-phase with each other. Here's what it looked like in operation:
Please accept our apologies for the unedited, very shaky, hand-held video.
It's a small step - a very small step, but it did demonstrate that the servos, controller, and software were functional. No Smoke! We felt really good.
It was also interesting to see how smoothly the servos move. Putting Gulliver, our KHR-1 robot, to a similar test sequence would have resulted in movements with very obvious and distinct steps, but the MANOI AT01 servo movements are so fine that it would be very hard to make out individual steps.
More to come...
Project M: MANOI Posts (English)
Kyosho MANOI AT01 Official Website (Japanese)