Update 18th June 2017: I submit an updated 3D image from the CAD-system and a video. The design "cleaned up" a bit during the work. I consider this a finished project and continue developing the robot in new version. Upcoming is an autonomous version and a slightly updated hardware configuration, using an ATmega328P chip directly instead of an Arduino board.
Just continuing with my robot concept. The new robot has roughly the same form factor as my first KITtyBot but 3D printed parts instead of acrylic sheets and balsa wood. The electronics are from KITtyBot - Arduino Pro Mini, 7.4V/500Ah LiPo battery, 5V/3A voltage regulator and cheep IR remote control to steer it. This time on a PCB board of my own design.
You might want to add one additional degree of freecome in the shoulder (or the waist) to allow the robot to turn more easily. Curious how you’ll do the waltking gait.
If you look closely at the top joint (shoulder) there are two servos forming a two degree joint.
The walking (and turning) gaits are done by solving some trigonometric functions in the Arduino. I submitted a description of the theory on my first KITtyBot posted here on LMR. This robot works roughly the same.
I have built and tested the robot. I will post pictures and film as soon as I have the time for it.
It seems I never took any pictures of the PCB before it was mounted (being in too much hurry it seems). Anyway the picture from my film clip:
I designed the PCB in Fritzing and since then I developed it a but further. I have a silk screen image of the PCB here which I think quite well describes how it will look the next time I order a PCB.
In the top right corner I added screw terminals for battery input (the unregulated voltage feeds the Pro Mini) and output to the 5V UBEC. The regulated 5V signal has it's connection in the bottom edge of the PCB (can be seen in the photo). The servo connectors are located in four "clusters" of three, one for each leg. I use the pins D2-D12 (leaving D13 for blinks and beeps) and A3 for the servo signals, A0 for voltage measure (dividing the 7.4V signal with two resistors located under the Pro Mini (either the bottom side of PCB or in the empty space under the Pro Mini created if it is mounted on headers). A1 is dedicated for the IR reciver with a female header (V, G and A1) that allows a mounting of a TSOP38238 IR reciever. I did breakouts for the other pins and some extra for VCC and GND to allow connecting more things.
So I am slowly adding more tings to the PCB to avoid having things "hanging" aorund the robot.
Nice video. I love the design. The utility of the hip joints is clearly evident in the videos. If I ever build a quad, I will likely study yiours for a head start.
