SurferBot V2: Switched Version

Inspired by a survival mechanism initiated by the honeybee trapped on the surface of the water, the SurferBot is a small robot that self-propels on the fluid surface. This low-cost and easily assembled devices is created by combining a coin cell battery with a vibrating pager motor. The SurferBot is able to move thanks to forces arising from a wave-generated, unbalanced momentum flux. This SurferBot differs from our other Surfer fleet as it has a longer battery-life and is capable of being switched on and off.

Needed for each SurferBot:

1. 1 cut out acetate sheets for the SurferBot body (ai file below)
2. 1 SurferBot housing with double sided tape on the bottom (stl files below)
3. 2 LR44 Coin Cell Battery (L1154F AG13 357 303 SR44 A76 Premium Alkaline Battery 1.5V Button Coin Cell Batteries)
4. 1 vibrating pager motor (10000rpm Self Adhesive Vibration Motor 10x3mm)
5. 1 3-Pin Slide Switch (SS12F15 5mm DC 50V 0.5A)
6. 1 LR44 Coin Cell Battery Holder (AG13 SMD Coin Cell Holder 14x15x12MM/0.55x0.6x0.47Inch)
7. 1 30-35mm length of 22 AWG wire stripped on both ends

Other Supplies Needed:

1. 1 tub, any size will do, filled with water

(Optional) For a giveaway kit:

1. 4" x 5" plastic bag

Acetate sheets were laser cut on Universal Laser System - Model 4.60 - 30W (Red: Power 50%, Speed 100%, PPI 10000 and Black: Power 5%, Speed 100%, PPI 1000)

Ensure that you all have all components needed including the 10x3mm pager motor, 2 LR44 coin cell batteries, battery holder, acetate sheet, slide switch, 3D printed body, and s30-35mm segment of stripped 22AWG wire (strip ~3-5mm off each side).

Place the batteries into the battery holder. Note that the battery holder has small print on it indicating polarity. Overall polarity in this circuit is negligible, but the batteries will slot in easier if the polarity is correctly aligned. Ensure that the batteries are facing in the same direction and are aligned with one another. Once both batteries are placed into the battery holder, place the battery holder into the back slot of the Surfer body.

Place the 3-pin slide switch into the Surfer Body. The orientiation of the switch doesn't matter here, but the switch should slot firmly and securely into the body.

Place the 10x3mm pager motor into the Surfer body. Face the motor downwards, such that the wires feed through the holes in the Surfer body. Flip the Surfer onto it's back for the following steps.

Using the 22AWG wire, slide into the battery holder and feed along the contour of the Surfer body before securing onto the closest pin on the switch. You can solder the wire onto both pins if you desire, but if you stripped the wires well enough, you may not need to.

Using the positive (red) wire of the pager motor, attach onto the middle pin of the switch. Note that if you mis-place the wire onto the wrong pin of the switch, the circuit will be disconnected and not function as desired. Again, if you desire, you may solder the wire to the pin, but ensure that you do not accidently solder the two pins together as you will short the circuit.

Attach the negative (blue) wire of the pager motor to the other terminal of the battery holder. Again, if you desire, you may solder the wire to the pin, but may not need to if you strip the wires on the pager motor well enough.

Gently peel the double-sided tape to attach the Surfer body to the acetate sheet. Turn on the switch to ensure the circuit is functioning as intended.

Once the circuit and Surfer is fully assembled, place onto the water bath and switch on. The acetate sheet should float on the top of the water surface. Release and get surfing! The battery enables the motor to run ~2 hours so feel free to disconnect and play til your heart's content!