Carbot Lite

Carbot Lite was built on commission with the idea of being a smaller carbot than my other versions. This version has only two suction cups, and was designed to not follow the normal radial style of the others. It has 3 4700uF capacitors in parallel, with a single 43x34mm Solar Cell providing 5V@ 40mA.

I typically use the MCP-112 450E for my solar engines, but I was concerned that the 4.7V trigger point would be too close to the max voltage output of the solar panel, so I opted for the 315E variant which triggers at 3.08V. This would result in less power to the motor, so I would have to make sure the spinner was light enough to get a few spins in. I also had to be careful to make sure the spinner was balanced, as this bot would be stuck to a window, and gravity would take effect.

The brass wire used as the frame is 12 gauge round half-hard brass wire. It was shipped coiled. So I had to find a way to straighten it out as best I could. I grew tired of using jumbo paper clips, which were actually steel and didn't solder as well as I wanted. Luckily I found this video on youtube which provided an elegant solution to my problem!

Sentinel

I took what was left of Fleet Beacon and added it to a Miller Solar Engine to create this bot. It is essentially two separate circuits on one frame. The first is a classic Miller Solar engine that charges up in the sun and manages to spin the entire robot for a few rotations. I used two 45x25mm solar panels in series for the spinner circuit, which equates to 10v at 30mA. Normally this would be total overkill for the circuit, as the voltage trigger fires at around 4.9v, but I wanted the robot to spin even in less than ideal conditions.

The second circuit is the leftover parts of Fleet Beacon, repaired and attached to the underside of the side solar panels. It is a dark activated pummer that blinks red LEDs for a few hours when the light is low enough.

I used some 1/8" channeled square brass tubing that I picked up from Ace Hardware for the frame of this robot, and I couldn't be happier with how it turned out. I love the look, and the strength is great too. For making angled turns, I clipped out a section of the tubing, bent it to the appropriate angle, then re soldered the edges together for extra strength. It also allowed me to tuck the winged solar panel wires into it to hide them quite effectively.

Overall I am very happy with this bot. It spins during the day, and blinks at night. Leaving for work in the morning he happily spins away, and coming home in the evening he will blink away until bed time.

HipHopper

My first experience with the 1381 voltage detector. This circuit used in HipHopper is the 1381-based solar engine. He is powered by a 24 x 33mm Panasonic cell connected to a 1.5F PowerStor super capacitor. His body is built on a paperclip chassis, and when firing, this robot will bounce all over the robot farm. Some robot builders call this style a Vibrobot.

1381's are increasingly hard to find nowadays as they have been discontinued. Luckily the folks at Solarbotics tracked down a direct drop-in replacement for the 1381 named the MCP112.