DYS 1306 3100kv thrust test

motor:
DYS 1306 3100kv

power:
3 cell lipo  (12,6v)

proplist:
Diatone 4045 Bullnose ABS
HQprop 4040 Bullnose ABS
Gemfan 4045 ABS
Gemfan 3030 ABS
Hobbyking 4025 ABS
RotorX 3040 Bullnose Triblade

The HQProp 4040 and Diatone 4045 cause the motor to overheat after just a few seconds on max power. These 2 props and all other 4 inch triblades and 5 inch props I used in previous benchmarks are not usable on this motor.

DYS 1806 2300kv thrust test

motor:
DYS 1806 2300kv

power:
3 cell lipo  (12,6v)

proplist:
HQprop 5040 Tri blade ABS/GR
Hobbyking 5045 Tri-blade
HQprop 5045 Bullnose
Gemfan 6030 ABS/CR
Gemfan 5040 ABS
HQprop 5040 ABS/CR
HQprop 4045 Bullnose Tri-blade ABS
Gemfan 5030 ABS
Diatone 4045 Bullnose ABS
HQprop 4040 Tri-blade ABS
HQprop 4040 Bullnose ABS
HQprop 4040 Quad-blade ABS
Lumenier 4040 Quad-blade ABS
Gemfan 4045 ABS
Gemfan 3545 ABS
Dalprop 3045 tri-blade

* update 04/07/16: added gemfan 3545, dalprop 3045, hqprop 4x4x4, lumenier 4x4x4

Multistar 2206 2150kv thrust test

motor:
Multistar 2206 2150kv (aka the baby beast)

power:
3 cell lipo  (12,6v)

proplist:
HQprop 5040 Tri blade ABS/GR
Hobbyking 5045 Tri-blade
HQprop 5045 Bullnose
Gemfan 6030 ABS/CR
Gemfan 5040 ABS
HQprop 5040 ABS/CR
HQprop 4045 Bullnose Tri-blade ABS
Gemfan 5030 ABS
Diatone 4045 Bullnose ABS
HQprop 4040 Tri-blade ABS
HQprop 4040 Bullnose ABS
Gemfan 4045 ABS
Hobbyking 4025 ABS

Ready to benchmark!

The RC brushless motor test bench (version 1) is ready.

The RPM sensor is made with an infrared LED and an infrared phototransistor (TCRT5000L). The IR LED constantly emits an IR light that is invisible to the eye. the phototransistor acts as a switch that is toggled by IR light. Every time a prop blade is between IR led and IR phototransistor the IR phototransistor switches off. In most RPM tutorials this on/off switching is counted during some time. e.g. 100 times a switch off during 250ms equals to 12000 rpm for a 2 bladed prop. But this means you'll only have an RPM readout every 250ms this would slow down my benchmarking.
To calculate the RPM I use the time difference between the switches, or the time difference between the blades. This gives me a RPM readout every turn of the prop. e.g. 4 miliseconds time difference between the blades equals to 7500 rpm for a 2 bladed prop.

Now I have all sensor data for this project. And I can start benchmarking my motors and props. The current PC application is a bit limited. It just start/stops a benchmark cycle and it captures all data. The data can be saved to a file or copied to clipboard. At the moment there is no fancy graph. But this can be done with any spreadsheet application because the saved benchmark file is a tab delimited csv file that can be imported in almost all spreadsheet applications.

RC Brushless motor test bench

My RC brushless motor test bench project is almost finished. I hooked up an ACS 712 30 ampere current sensor. This sensor will read out the current consumption of the motor and send it to the arduino board. I also made a basic voltage divider in order to read out the battery voltage with the arduino board.

I currently have programmed the arduino board to read voltage, current and thrust. With a very basic command set and human readable output it is possible to control the arduino (test bench) completely by hand with arduino IDE serial monitor feature.

But I also created a small PC application that makes it easier to control to board and run a pre programmed benchmark sequence. With this small program it is possible to save or copy the incoming data. This application is created with the processing IDE and is java based. So it should run on every java compatible platform (operating system)

The ACS 712 sensor is a cheap one from ebay. In order to get it to
work well you should add a capacitor on the ACS 712 FILTER pin. To achieve this you will need some soldering skills. Without the capacitor this sensor is useless in this application. I used a 10nf cap.

Next step is to integrate a RPM counter.

Downsize the Dozer

I would like to downsize the Dozer 260 (class 250) to a Dozer 210/200 (class 200). These class 200 multirotors are mostly equipped with 4 inch props and AUW < 400 grams. To achieve this I need to build a smaller frame and reduce the weight on all parts (electronics, battery, motors, esc). To find the best drive (motor/prop) combination I'll build a fully automated and computer-controlled motor test bench. This should allow me to measure thrust/efficiency for a lot of motor and prop combinations fast and accurate.




I'll use an arduino board to control the ESC and to read all sensor values. The arduino will then send all data to the PC via a usb or bleutooth connection.




I used a Hobbyking thrust stand and disasembled the sensor/lcd section. Then I connected the weight sensor of this thrust stand to an ADC (analog to digital converter HX711) and that ADC is connected to the arduino which reads the value.




The weight sensor measures the thrust generated by the motor and prop. I'll also hook up a RPM meter based on an IR emitting and IR receiving LED. This will provide the rotation speed of the motor/prop. And last I'll also add a current sensor to measure the motor/prop power consumption. All this data will be read by the arduino board and send to my PC.

FPV practise @ home

Step by step building guide

Step1:
Attach the front and rear arms to the bottom plate.
you will need 4 x M3 x 30mm screws.







Step2:

Mount the nylon spacers on the frame. The front spacers are 40mm long and mounted on the M3 screws from step 1. The center spacers are also 40mm long and attached to the bottom plate with M3 x 6 mm screws. The rear spacers are 20mm long.

Because I could not find 40mm nylon spacers I used 2 x 20mm.




Step3:

Mount your motors and esc to the frame. Connect all power cables and fix them to the bottom plate. Make sure they come out at the rear part of the quad between the rear nylon spacers. This version does have a powerdistribution board (PDB), but that is planned in the next version of this frame.






Step4:

Mount your FPV camera, flight controller and rc reciever on the clean section board. To mount the flight controller I used 6mm nylon spacers. The RC receiver is fixed with tape. I use is a board cam that I mounted on to the board with a 3dprinted part. This can be attached to the clean section board with two 6mm M3 screws (drill extra holes in clean section plate) or just glue it to the clean section board with some epoxy.
Then mount the clean section plate on to the frame with 6 anti vibrating rubbers.




Step5:

Mount the top battery plate on to the frame. Use four 6mm M3 screws and add two 20mm nylon spacers. Make sure when mounting the battery top plate that the cables connected to the flight controller on the clean section do not touch the top battery plate. Else the antivibration effect will be lost.





Step6:
Last step is the top vtx plate. Before mounting the plate to the frame first attach your video transmitter, on screen display module, and vtx antenna to this plate.

On my multirotor I used an Immersion 5.8ghz 25mw video transmitter in combination with a Immersion spironet antenna. And an HK E-OSD module. I just used some tape to attache everything to the plate. I also isolated the open copper parts from the vtx antenna.

Then mount the top vtx plate to the frame with four 6mm M3 screws. The vtx power cable comes out at the back and can be connected to the battery. The video cable goes down and can be connected to the camera.

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complete parts list

This is the complete parts list in order to build this frame (just the frame not the full multirotor)
1 x Dozer 260 bottom plate
2 x Dozer 260 arm
1 x Dozer 260 top battery plate
1 x Dozer 260 top vtx plate
1 x Dozer 260 clean section plate
1 x Dozer 260 FPV camera case (optional, for users with fpv board cam like me)

1 x Set of nylon spacers 20mm (tapped)
1 x Set of nylon spacers 20mm (threaded)
1 x Set of Vibration Dampening Balls

4 x M3 x 30mm screw + nut
12 x M3 x 6mm screw
2 x M3 x 6mm screw + nut OR epoxy glue (depending on how you prefer to mount the fpv camera case)


Minimal tools you need to build this frame:
- 30cm measuring stick.
- pencil.
- hand saw (for cutting metal)
- screwdriver to fasten the M3 nuts
- handrill with 3mm and 7mm drill (for drilling metal)
- 1.5mm carbon fiber sheets to cut out the different plates.
- 15mm square aluminum tube to cut out the different arms.
- copper wire & lipo battery plugs


The next list are the parts I used to make a complete flying fpv race quad copter
4 x DYS 1806-2300kv brushless motor
2 x Gemfan 5030 Multirotor ABS Propellers CCW & CW set
4 x HK Blueseries 12 brushless speed controller
1 x MultiWii 328P Flight Controller
1 x RC receiver (depending on the RC system you use)
1 x Sony 700TVL CDD camera
1 x Immersion 25mw video transmitter
1 x HK on screen display
1 x ImmersionRC 5.8GHz Circular Polarized SpiroNet Antenna V2
1 x Turnigy nano-tech 1800mah 3S 65~130C Lipo Pack

FPV cam case

I'm using this sony 700TVL CCD board camera . This camera has no case and needs someting like a case in order to be mounted in the quad copter. Therefore I designed a very basic open case that holds the fpv cam. 3D printed with ABS or PLA it will weigh about 5 grams.

This case is designed for the 32mm board cam standard. Most 32mm board cams should fit in this case. 38mm board cams will not fit in this case nor in the frame.

I glued this case to the clean section plate with epoxy. You can use the 2 holes at the bottem to screw it to the plate with two 6mm M3 screws. But then you will have to drill two more holes in the clean section plate (these are currently not present on the current design)



These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

Top plate (vtx)

 This is the second top plate for the dozer 260 race quad. This section will house the video transmitter (vtx) and on screen display module (OSD).

I used a 1.5mm thick carbon sheet. Width is 54mm. You can vary the length from 70mm to 100mm depending on the space you need to mount your vtx and/or osd module. I'm using a immersion 25mw vtx and E-OSD module from hobbyking. For my multirotor I made this section 100mm long.

The large hole is optional. I use it to mount the vtx antenna. Carbon fiber is condictive, some poeple report damaged vtx modules when attaching the vtx antenna to a carbon fiber frame. Therefore I added a rubber arround the vtx antenna so it can not make contact with the carbon fiber.






These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

Top plate (battery)

This is one of the two top plates for the Dozer 260 multirotor. This section will hold the battery.
The battery is mounted on top of the plate with a velcro battery strap. To make sure the battery does not slide off the smooth carbon fiber surface, I added some soft foam (3mm) with dubble side tape.

Depending the size of your battery you will need to change the location of the 7mm holes. These holes are used to hold the battery strap in place. These holes are currently set for 3cell lipos 1800/2200 mAh

outside dimensions: 140x54mm
I used a 1.5mm thick carbon sheet.


These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

clean section

The clean section will be seperated from the rest of the frame by vibration isolating rubbers.
The FPV camere, flight controller and RC receiver will be mounted on this clean section.

For my multirotor I used these Vibration Dampening Balls . If you use other vibration dampening balls you need to adapt the 7mm holes to the size of your dampening balls on this clean section but also on the bottom plate.

Outside dimensions: 150x54mm. This sketch is 1.5mm thick plate. For my current race quad I used a 1mm thick carbon plate. Because this clean section is completele protected by the frame (crash cage), this clean section plate does not have to be strong.

This board is designed to mount 45mm compatible flight controllers. If you have other type of flight controller you may want to adapt the location of the 3mm holes in the center of the plate.


These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

Arms

 I currently made the arms that hold the motors with 15x15x220mm aluminum tubes. Carbon fiber tubes with same dimensions would safe about 40 grams but these are not available in local hardware stores. Even on internet 15mm square carbon fiber tubes are hard to find.

outside dimension: 15x15x220mm
inside dimension: 13x13x220mm

Note that you will have to adapt the motor mount holes according to the motor you use in your project. I use DYS 1806 motors and the holes are drilled for 16mm mounting. Most 1806,2204,2206 brusless motors will fit.


Arm top view (small holes 3mm, large holes 7mm)







Arm bottom view (small holes 3mm, large holes 7mm)






To reduce the weight of the aluminim tube I drilled a lot of 7mm holes. This reduced the weight of one arm from 44 grams to 36 grams. These holes are not in the sketch but are visible on the introduction photo (first blog).

These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

Bottom plate

The bottom plate is a 1.5mm thick carbon fiber sheet. A 1mm sheet is not stiff enough and a 2mm sheet will make the quad to heavy.

Outer dimensions 200mm x 54mm
8 x 3mm holes
6 x 7mm holes

As I only have basic handtools to cut the sheet and drill the holes. I drilled the 3mm holes with a 3.5mm drill this way I have some tolarnce when I mount all other parts on it.






These 3D sketches are available on my 3D warehouse sketchup webpage . Select the Dozer 260 FPV race quad copter collection to get al sketches for this project.

The Dozer 260 multirotor

The Dozer 260 quad copter is my new project in order to create a FPV racing multirotor that meets all my requirements. Before this I used a Hobbyking FPV 250 Low Hung frame as fpv racing platform. (see this blog). I was very happy about this frame. But it had one downside. The low hung cage came lose every time you touch the ground or made a little crash.

The goal of this project is to create a multirotor with specs:

- FPV 250 class quadcopter frame

why? Because  a 250 class multirotor is the best fit. A smaller frame would not be able to carry my current electronics (FC, CAM, VTX,...), A larger frame would not be easy to fly in my garden.

- High performance

I'm counting on a 3 to 1 thrust to weight ratio. I got a lot of dys 1806 2300kv motors and 3 cell lipo batteries. In combination with 5 inch props and a total AUW < 650 this should give me the performance I need for racing.

- Durable frame

FPV racing equals to crashes. I don't like to do constant repairs every time I gently touch the ground. A strong frame will result in higher weight.The frame should be strong but not to heavy.

- Clean and dirty section

In all my projects I work with a clean and dirty section. This makes the frame construction more complex and a little bit heavier but it has great results on stability. I can fly my multirotor with unbalanced props and cheap low quality motors.
- DIY
The frame may not be to complex so everyone can join this do it yourself project even if you only have basic handtools. The parts used to build the frame will be parts that are available everywhere, This makes it easy to repair.