Now both hips are done, and with one knee in place I'm thinking about some of the other adjustments I will need to make and parts I need to order. The servos will have to come out again so I can add the top piece which will hold the controller, battery, and also hold the legs together.
We now have half of the robot built, and a few days having passed, my package has arrived from Lynxmotion. A nice thing they do is include extra screws in a sealed plastic bag. This way, if you strip a tiny screw or crush a nut with pliers, you don't have to lose days waiting on another order.
The on/off switch is ready to be added to the SSC-32 board and includes the plug for the battery. I'm using a 1600mA battery from Lynxmotion, which I picked up for my other project. My spare 1500mA battery has not been converted to this larger power plug size yet.
I also have the feet needed so my biped can stand up.
With all the parts received, I'm able to finish putting him together. Here is a picture after adding the previously missing C brackets.
A closer look at one of the legs.
On to adding the feet with the servo brackets! On my first try I guessed that they were placed more to the back than the front of the foot, like on a human. I ended up having to take them apart and move the feet closer to the center for better balance.
We now have two legs which aren't attached to each other. I didn't get the U channel (as when I ordered my parts, it was not in stock) so instead I used some scraps of UV acrylic I got from A.C. Ryan that I used in my How-to build a quick fan grill. I cut a small piece and bent it into an L shape using a torch and a 5" vice.
Heating it quickly did cause the acrylic to bubble a little bit and my bend wasn't exactly down the center of the piece. So I decided to square it up a little more. I taped it up and figured out about 1" on each side of the bend was.
One of the sides needed more cleanup than the other, so I went to the band saw to cut the edges straight. Next, to get the holes lined up, I used one of the L brackets as a template for the screw holes. A 4-40 drill bit from my tap set (the same size as used on the Lynxmotion SES) made the holes. Again, I wasted time by being lazy and not measuring, as I ended up with a piece that was too small and had to make another one. You can see I missed it by 3-4mm. I have the legs pushed tight against each other in the image below.
Second try, I made certain to measure first and had a little extra on the sides. I also drilled out the hole for the switch and two holes to hold the SSC-32 board. My placement of the board is higher than Lynxmotion's, and causes a little bit of instability of times, but when you use the SEQ program on a computer to control the SSC-32, you can take that into account.
The first movie I made using the SEQ program and Lynxmotion's stand up program. It looks more like the bot is having a fit than actually standing up. Below are links to movie files of him doing some of the "tricks" he knows.
Stand up - not working
Bart - stand up
Bart - one-step-82
Bart - side 2 side
Bart - kick a ball
Bart - takes a bow
Lynxmotion should have the kit finalized and in stock by my posting of this, as well as real instructions for building your own. I have to thank the owner, Jim, of Lynxmotion for building the example and for all the help he has given me.
