FPV Nightvision Explorer (STEM/solderless)

hey there. this model was designed to teach many simple techniques in a fun and easy way. to keep it safe for younger makers, this entire project is solderless and for convenience it only requires the screws included with the servos. I feel comfortable saying people as young as 10 should be able to complete this project in a weekend or 2 with parent/adult supervision and in some cases, minor assistance. this small RC rover can explore in complete darkness and is well equipped to handle most interior surfaces and small obstacles. it can even do some offroading but the tracks tend to eat grass like a goat so be careful ;)   Enjoy!!

PARTS LIST:

4x 608 skateboard bearings

3x 5mm 850nm IR led (this is just what i used and suggest) https://www.amazon.com/dp/B01BVGIZIU?psc=1&ref=ppx_yo2ov_dt_b_product_details

1x servo lead 40-60mm(mine was salvaged from a dead servo. look for a quality guage of wire. too small and the wire could melt from the amp draw)

programable RC plane transmitter(programable is needed for the “tank steering”)

1x 18650 2s li-ion RC pack(the battery slot was designed around these exact packs) https://www.amazon.com/dp/B089W89KCP?psc=1&ref=ppx_yo2ov_dt_b_product_details 

TX02 FPV all-in-one unit 

5.8ghz fpv headset or screen

2x generic 9g servo

1x 150-250mah 1s lipo for TX02

1x 3A 5V UBEC(the smaller, the better)

30mm 3mm heatshrint tubing

OPTIONAL: CA glue, small zipties

PRINT SETTINGS:layer height/bottom-top layers/wall count/supports(20% infill on all)

wheelset:.3/3/2/Y

shell:.2/3/2/N

chassis:.2/3/3/Y

track:.3/0/2/N(TPU and print hotter than usual for durability)

THE BUILD: start by modifying the 2x 9g servos with the 360 degree mod of which many tutorials can be found on youtube. then install both servos with the white connector side pointing towards the rear. thread the servo lead into the body and slide the servo at around a 45 degree angle and it will click past the wheel retainer. use the included screws to secure the servos and the screws are easily accessible through the 2 holes on either side of the wheel retainers. Next step will be the LEDs. cut the leads to 14mm. the holes have the flat side(negative lead side) keyed to show proper orientation or the LEDs. using medium pliers, gentle press each LED into its slot. should be very snug so no need for glue. now fold in the leads of the middle LED towards the out 2 and the inner leads  of the outer LEDS towards the inner. bend the leads where they meet in the middle and twist them together and fold down into the recessed valleys, you can use CA glue to insulate the leads but as all other wires in the chassis are already insulated, i chose not to. now take the spare servo lead and remove the signal wire and strip away about 10mm of the positive and negative wires insulation. slide 15mm lengths of heatshrink tubing over each wire. fold the remaining LED leads midway 90 degrees upwards and starting at the bend, wrap the wires up the lead, fold the leads over on themselves, slide the tubes over and heat the tubing for a secure connection. now fold the leads down to lay against the inner body. 

now for the hardest part of the build, wire management! this will require planning and multiple layout attempts most likely but will be greatly simplified by using a micro receiver as long as it has PWM output and servo plugs(you can go even smaller but soldering would be required). i removed the shell from my frsky DR4-II receiver, plugged the ubec, 2 servo leads, and LED servo lead into the the ports making sure the servos went to channels 2 and 3 while the other 2 can go wherever. then the receiver and ubec where secured under the battery slot with the leads pointing towards the from. at this point you may have to fold and ziptie wires into neat and organized bundles. hard part over!

time for modifying the TXO2. in order for the nightvision to work, we need to remove the IR filter from the TX02 camera. tutorials can be found on youtube but ive included a quick vidieo so show the desired result

now insert the 608 bearings into the front roadwheels(flat outer side) and slide into the front shafts. its a nice press fit so no need for glue. then insert the bearings into the rear road wheels. cut the symmetrical/long and skinny servo horn to match the recess on the other side of the rear roadwheels and press fit them in to the road wheels with the center cup pointing outwards. gently bend the wheel retainers outwards and slide the road wheels in to where the bearing slides into the recess in the wheel retainer and the cup of the servo horn is on the servo. now you can slowly roll the tracks over the road wheels. the TXO2 fits into a recess on the top front of the shell and i suggest holding it down with very small dabs of CA glue and the 1s lipo can be velcroed to the rear center. place the battery into its slot, plug in and the shell snaps over the chassis at 4 points using the holes in the wheel retainers. only thing left to do is program your transmitter for flying wing mixing of which you can find tutorials for your radio on youtube. 

now get out there and enjoy!!!