Wednesday, August 15, 2018

IoT Platform Weight 250 Grams Breakdown

Sorted by the weight of the components. Half of this page and half of the parts weigh less than 1% of the craft's total weight each part set. 70% of the parts weigh less than 10 grams each. 

GensAce 900mah 25C battery set - 75.4 grams 

The 3 cells weighing 56.7g on the right and the 3 cells weighing 56.5g below are cleaned from 2 different packs of GensAce 900mAh. When the 2 packs are trimmed out of their top cell, they weigh 75.2 grams combined as pictured below on the right. If you zoom in on the green PCB, you can see that B2 and B3 are saved and B1 is trimmed out. Worst case both packs are the heavier pack adds 0.2 grams combined, 75.4 grams.

GNB 650mah 60C lipo battery pack - 60.3 g

GNB 520mah 80C lipo battery pack - 55.4 grams

EMAX 2808 660KV Motor - 53.8 grams

Below first 5 photos are of the same motor. Carving out the excess base and trimming out excess wires save 2.6 + 1.8 = 4.4 grams. The bell weighs 23.2  grams consistently. The modification to thin wire saves (30.6 + 23.2) -  52.8 = 1g. The 6th photo is of another motor. The stater weighs 52.8-23.2 = 29.6g to 28.7g with thinned wires, ot, 30.6g  to 29.7g with original wire. Worst case 30.6 + 23.2 = 53.8  grams.


T-Motor 4004 kv400 motor - 47.9 grams

The weight of the bell is between 17.3-2.4=14.9 and 17.6-2.5=15.1 grams. The lighter blank stater(22.2g) produces a 32.2g to 32.3g stater. The weight of the stater is very close to the maximum weight of the milligram scale and can damage the milligram scale, hence the multiple weighing on the coarse scale to estimate the true weight. Worst case with the heavier bell and the 0.5g heavier stater(22.7g blank stater) is 32.3+15.1+0.5=47.9 grams.

Blade 230 main frame - 23.5 grams

The main frame comes between 26.1 grams and 26.3 grams. 
The first 2 photos are of the same frame. Cleaning the frame reduces 4.5 grams maximum resulting in between 22 (omitting carving main shaft cage front and servo cage, 0.2 grams each respectively) and 22.2 .

The hardware screws weigh 1.3 grams.  So the installation is between 22+1.3=23.3 and 23.5 , worst case 23.5 grams.

E-Flight BSR main frame - 22.8 grams

The following first 2 photos are of the same frame. Cleaning the frame reduces 0.9 grams maximum resulting in between 20.5g and 21.7g. The hardware screws weigh 1.1 grams. So the installation is between 20.5 +1.1=21.6g and 22.8g , worst case 22.8 grams.

Tarot 212mm Blade For Trex250 - 17g

Oxy2 210mm main blade - 14.6(carbon)-17(plastic) grams

Runcam Thumb - 14.5 g

Emax 9051 servo set  - 13.5 grams

The servos in the 2 photos, on the right and below, are 2 different servos from 2 different sales. The tab belongs to the servo on the right. The entire servo with the tab weighs between 0.40+4.48 =4.88g and 4.9g. The tab weighs 0.4g .
Worst case, the total weight of the 3-servo set is (4.9-0.4) x 3 = 13.5g.

Caddx Turtle camera - 9.5 grams

Raspberry Pi Zero W - 8.9 grams

Favorite Little Bee 20A ESC - 7.6 grams

2.64g (with trimmed 20AWG power input wires) + 0.71g (the trimmed wire) = 3.35g for the unit for tail motor. Remember, the trimmed scrap is still needed to wire the battery to the ESCs.  3.35g + 1.23g x 4cm/5.5cm (3 black motor wires) = 4.24g for the unit for main motor. 3.35g + 4.24g = 7.59g total.

HGLRC 1106 2400kv motor - 7.2 grams

OXY Heli Sport Main Grip Set - 6.2 g

Beitian BN-180 GPS - 5.6 grams

Microheli Precision CNC Titanium Main Shaft W/ Collar V950 - 5.5 grams

Lynx Blade 230 carbon fiber tail boom -  4.8 grams

Blade 230 swash plate - 4.4 g

Align 250 DFC Grip Set - 3.7 g

Blade 230 landing skid set - 3.1 grams

HGLRC FD411 - 2.8 g

The set includes the DFC bolts and 2 washers for blade bolting, but the DFC bolts and the washers are not used

Acrylic sheet 0.08 inch - 2.6 grams JST-XH charging plug and cable - 2.4 grams

 E-Flight BSR servo push rod set - 2.2 grams

The original set on sale is shown as 2.0 grams. The 1 extra ball link pair with rod needed to connect to DFC pin is shown as 0.4 grams. The long rod's non-threaded part to be trimmed out is 0.6 - 0.4 = 0.2 grams. So the 4 links total is 2.0 - 0.2 + 0.4 = 2.2 grams.

The long rod, after cutting out the center, non-threaded area, has 2 short segments, each for 1 rear servo rod. One of the original rear rod is used for the front rod. The second original rear rod is used as one of the DFC rod. The extra ball link pair from a second purchase of this item has 1 rod for the second DFC link. The extra ball link pair from the second purchase of this item has 2 ball sockets for the 2 DFC links.

16A ESC - 2.1grams                                                           T-Rex 250 landing skid - 2 grams

Microheli Blade 230 main shaft - 1.8 grams XT30 connector -  0.9-1.7 grams

TBS Unity Pro32 Nano - 1.4 grams

Only half the wires utilized. 1.053 + (1.739 - 1.053) * 5 / 9 = 1.43

Gemfan 4025 propeller - 1.5 grams

Blade 180 CFX main rotor hub - 1.4 grams

Blade 180 CFX feathering shaft - 1.4 grams

Velcro tie 3/4 inch with adhesive - 1.4 grams per 14 cm

0.8g / 8cm = 0.1 grams per cm . 3.5cm for bottom attachment for battery. 4.5cm for top attachment for battery. 6cm for battery itself. 

M1.5 x 6mm self-tapping screw - 1.4 grams per 18 pcs

The scale is calibrated with the small bag. 2 screws for each of the 2 custom servo brackets, 2 screws for each of the 3 servos' tabs, 1 screw for the front server lower tab, 4 screws for landing skids, and 1 screw for each of the 3 servo arms. 2x2 + 2x3 + 4 + 1 + 1x3 = 18pcs. The front servo needs thicker fastener to fit the original larger bores. 

Runcam Nano 3 - 1.2 grams

AKK IPEX 5.8GHz antenna - 1.2 grams            Oxy2 Sport DFC Bolt Set - 1.2 grams

FrSky XM+ RC receiver - 1.2 grams                    TBS Crossfire Nano - 1.2 grams

Runcam camera bracket - 1.1 grams

Solder - 0.7-1.1 grams per 35-62 points

The 4-8 soldering points adds 0.1 grams, average 6 points. The wires in the first picture have not been pre-tinned in at the cuts. The reading oscillates between 3.6 and 3.7 in the second picture with 4 soldering points, and it settles at 3.7 in the third picture with 8 soldering points.

The solder is a tin-lead alloy and the density is about 9 times that of water. For joining the 22 AWG, wire lead is 3mm in length,  0.4mm cross section area pre-tin on each side of the wires then joined. So, 2.4mm cube per job, and the weight is 0.1cm x 0.1cm x 0.1cm x 9g/cc x 2.4 = 0.021 gram.

Original build has 3 main motor joins, 9 tail motor joins, 2 power distribution points, 2 battery plug points, 2 power tapping on the buck converter, 2 power tapping far end, 8 points on raspberry pi, 3 points on receiver, GPS 4 points. 35 points.

Adrenaline diving build relocates raspberry pi's points to camera and VTX, then 3 servos needs 3 points each, 2 ESCs needs 2 points each. 35+13=48.

Endurance build needs extra 7 points for ESC build and 9 points for battery build. 48+16=64.

Picoblade 1.25mm 3pin 10cm set - 1.0 grams

The manufacturer specified 10cm length includes the male plug 0.5cm and the base of female socket(but not the actual socket) 0.5cm.
The raspberry Pi's power pins or the FD411's camera pins need 8cm(8.5cm including the socket) female half wire for powering or for signaling. That leaves 2cm 3 wires to be soldered on the RF receiver of the craft. In case of video signaling, the male half of the wire set needs another 0.5cm of the plugs itself and another 0.5cm wires. So the male half has 9cm left to solder on FD411's sbus pins for connecting toward the radio receiver. So, the RF receiver has 2+9=11cm distance from the flight computer. This is the same distancing provided with CC3D atom's main port(RF receiving port) wire set.

4x8x3mm bearing set - 1.0 grams

E-Flight BSR anti-rotation bracket - 0.9 grams

One screw is not used because we use custom M1.7 long screws.

Wolfwhoop 5V 3A buck converter - 0.8 grams

24 AWG enameled wire - 0.8 grams per 45cm

7.5cm for 2 power input of each of the 2 ESCs. 5cm for each of the 3 main motor poles. 

CHENYANG Ultra Mini DM Micro USB 5pin OTG Adapter - 0.7 grams per pair

Zip tie 2mm trimmed - 0.7 grams per 5 pcs

Clear mounting tape - 0.7 grams per square inch

Pictured here is 1 inch square. The CC3D board's width of 19mm is 75% of a inch. Either CC3D or FD411 needs 3 layers on the front and 1 layer on the rear from the 4 portions of 6mm, 6mm, 8mm, and 8mm. The remaining is used to mount either GPS(for FD411) or Raspberry Pi(for CC3D).

 ABS 4x4mm struts - 0.6 grams 4.4cm

Each of the 2 pieces is 2.2cm long. Servos spaced 1.8cm from fastener to fastener. Total width is 2.6cm, but the 0.8cm ends are tapered off. Counting the ends at the centers of the slopes. 1.8cm+0.4cm = 2.2cm .

Picoblade 1.25mm 2-pin connector set - 0.6 grams

Enameled 28 AWG wires - 0.6 grams per 111cm

Servos need 4cm(including the plug) of the female half to plug in to the 5 volt buck converter. The male half provides 4cm(including the plug) to tap power from the same buck converter for either the video transmitter or the raspberry pi. The scrap 2 sets of 4cm bare wires tap the (main+tail) motor signal pads and the flight computer vbat pads.

Servos need 4cm(including the plug) of the female half to plug in to the 5 volt buck converter. The male half provides 4cm(including the plug) to tap power from the same buck converter for either the video transmitter or the raspberry pi. The scrap 2 sets of 4cm bare wires tap the (main+tail) motor signal pads and the flight computer vbat pads.

Blade 230 anti-rotation bracket - 0.5 grams

M2x4-6mm bolts with nuts set - 0.5 grams

Previously shown with BSR anti-rotation
bracket that the 1 unused screw is 0.1 gram.

Velcro tie 5/8 inch without adhesive - 0.4 grams per 10cm

Mounting inch squares - 0.3 grams per square inch

The FrSky XM+ needs a full square on the antenna, but 3 small strips can be carved out for attaching the ArduCam camera. TBS crossfire RF receiver needs 2/3 of a square to make 4 strips for fixture of antenna, and the remaining 1/3 splits to 2 for Runcam Nano3 camera. 

Oxy2 Sport DFC rod set - 0.3 grams

Previous weighing of Blade 180 CFX main hub had 1.4 grams. The DFC rod set is hence 1.7-1.4=0.3 grams.

Heat Shrink Tube 2.5mm - 0.3 grams per 10cm

0.6 grams x 10cm / 24cm = 0.25 grams 

M1.7 screws - 0.3 grams 2 pcs

Either taken from landing skid set or M1.7x8 screws weigh the same

Packaging tape 3/4cm width- 0.5 grams per 35cm

Endurance battery needs 2 9cm ties for cells and 2 5cm wraps and a 7cm split wrap for the charging wires.

M2x10mm bolt - 0.3 grams

SanDisk 32GB SD card - 0.2 grams

Heat Shrink Tube 1.5mm - 0.2 grams per 10cm

Pinion Gear .5 Mod 081.5A - 0.1 gram

1.2 / 19 = 0.063 = 0.1 rounded to nearest tenth of a gram.

Nylon M2 washers - 0.1 grams per 6-8pc       Kevlar string - 0.0 grams per 30-50cm

0.055 x 6 / 3 = 0.11  g                                                     2.5 * 3.14 * 4cm = 31.4cm
0.055 x 8 / 3 = 0.147g                                                     0.025 * 50cm / 31.4 = 0.0398g