Making the robot MDi #4 - part 3: pan/tilt mechanism of the chest

     Hello guys! Just a short update...

     I've shown this part earlier... but now it's ready!

     Although being small, it is very important... as it gives 2 DOF to the chest and joins the chest to the base.

     Below you can see all the Makeblock parts used in this step of the project.

• 1X D Shaft 4x56mm;
• 2X Timing Belt 112MXL - 140T;
• 8X Plastic Rivet R4120;
• 2X Socket Cap Screw M4x16 - Button Head;
• 14X Socket Cap Screw M4x14 - Button Head;
• 6X Socket Cap Screw M4x8 - Button Head;
• 2X Headless Screw M3x5;
• 3X MG995 Servo Hub;
• 1X Shaft Connector 4mm;
• 4X Timing Pulley Slice 90T-B;
• 2X Timing Pulley 90T;
• 1X Gear 48T;
• 1X Bracket U1;
• 3X Plane Bearing Turntable D34x24mm;
• 2X Timing Pulley 62T;
• 4X Timing Pulley Slice 62T-B;
• 1X Gear 16T.

     I'm a bit in doubt about the field of the "pan" movement... with the gear reduction it's limited to about 90 degrees. I have to see it in action to decide. If I want a larger field, I have to remove the limitation of the servo motor and exteriorise its potentiometer. Well, let's see...

Making the robot MDi #4 - part 2: fiberglass chest, arms preview and new parts received

     I would like to have finished the chest, but he suffered a small accident... yes, he fell to the ground when I was preparing it to apply spray primer... but it's repaired and fine now!

     I have uploaded a video of the Pepakura work and another that shows many steps of the fiberglass work.

     Now the chest is closer than ever to be ready. And it's super lightweight. I just need to finish some custom features that will be made with polystyrene (high impact polystyrene) sheets. When it is fully ready, I'll weigh it.

     Below you can see that I used polystyrene sheets in some flat areas. Certainly with fiberglass I could not do it so flat. And on the side became with a suitable reinforcement, where the arms are installed (3 layers of 2mm polystyrene).

     I was a bit concerned about the DC motors for the treads, but fortunately I found good ones with 25 kgf-cm and 233 RPM @ 12V at a reasonable price.

     I do intend to finish in the next days the pan/tilt mechanism.

     See you guys!