Testing | Tarunsrcplane

Thrust Test 1

Using the 1806 2280kv motor and 20A ESC.

Battery was placed on weighing scale first to determine accuracy, returned a value of 67g for a 67g battery.

6x3 propeller was placed on the motor.
Motor is connected to ESC leads so the motor spins reverse of normal operation.
- Propeller applies thrust into the direction of the scale allowing for accurate readings.
ESC and 3 servos were connected to receiver to provide a more accurate testing set up.
Thrust measurements taken at intervals of 25% up to 100%.
Step 4 was repeated for 3 trials of 6x3 propeller.
Steps 1-5 were repeated for 6x4 and 6x5.5 propeller.

Table 1. Thrust Test 1

Testing Conclusions

Motor was very hot to the touch after 6x4 and 6x5.5 tests.
- Needed 5 minutes to cool off after each test.
Battery started at an approximate average of 4155mV per cell and ended at 4045mV.
The motor produced a maximum of 78g of thrust during trial 1 of the 6x3 propeller.
The maximum thrust consistently dropped off at larger propellers.
- 62g during trial 1 of 6x4.
- 66g during trial 1 of 6x5.5
Perhaps the larger propellers were too large for this motor.
Need to conduct a similar test using smaller motors.

Thrust Test 2

Continuation of thrust test 1 using the 1806 2280kv motor and 20A ESC.

Steps 1-5 of thrust test 1 were repeated for 5.3x3.5 and 5.5x4.5 propeller.

Testing Conclusions

Motor was sputtering during testing and would not produce any significant thrust.
Perhaps, the motor was damaged during test 1 or was faulty from arrival.
Motor does not seem usable anymore.

Thrust Test 3

Using a larger 52g 2212 1250kv motor and 30A ESC.

I believe thrust test 1 damaged the previous motor due to reversing the motor's spin but not placing the propeller on the motor upside down. This led to increased an increased load on the motor and larger current draw while producing less thrust, which overheated the motor.

Steps 1-5 of thrust test 1 were repeated for 5.3x3.5, 5.5x4.5, 6x3, 6x4, and 6x5.5 propellers with the addition of placing the propellers on the motors upside down.

Table 2. Thrust Test 3

Testing Conclusions

Motor was barely warm to the touch after running each test.
- Needed no cooldown time unlike thrust test 1.
Battery started at an approximate average of 4165mV and ended at 3980mV.
The motor produced a maximum thrust of 354g during trial 1 of the 6x5.5 propeller.

Thrust Test 1

Using the 1806 2280kv motor and 20A ESC.

Battery was placed on weighing scale first to determine accuracy, returned a value of 66g for a 67g battery.

6x3 propeller was placed on the motor.
Motor is connected to ESC leads so the motor spins reverse of normal operation.
- Propeller applies thrust into the direction of the scale allowing for accurate readings.
ESC and 3 servos were connected to receiver to provide a more accurate testing set up.
Thrust measurements taken at intervals of 25% up to 100%.
Step 4 was repeated for 3 trials of 6x3 propeller.
Steps 1-5 were repeated for 6x4 and 6x5.5 propeller.

Table 1. Thrust Test 1

Testing Conclusions

Motor was very hot to the touch after 6x4 and 6x5.5 tests.
- Needed 5 minutes to cool off after each test.
Battery started at an approximate average of 4155mV per cell and ended at 4045mV.
The motor produced a maximum of 78g of thrust during trial 1 of the 6x3 propeller.
The maximum thrust consistently dropped off at larger propellers.
- 62g during trial 1 of 6x4.
- 66g during trial 1 of 6x5.5
Perhaps the larger propellers were too large for this motor.
Need to conduct a similar test using smaller motors.

Thrust Test 2

Continuation of thrust test 1 using the 1806 2280kv motor and 20A ESC.

Steps 1-5 of thrust test 1 were repeated for 5.3x3.5 and 5.5x4.5 propeller.

Testing Conclusions

Motor was sputtering during testing and would not produce any significant thrust.
Perhaps, the motor was damaged during test 1 or was faulty from arrival.
Motor does not seem usable anymore.

Thrust Test 3

Using a larger 52g 2212 1250kv motor and 30A ESC.

I believe thrust test 1 damaged the previous motor due to reversing the motor's spin but not placing the propeller on the motor upside down. This led to increased an increased load on the motor and larger current draw while producing less thrust, which overheated the motor.

Steps 1-5 of thrust test 1 were repeated for 5.3x3.5, 5.5x4.5, 6x3, 6x4, and 6x5.5 propellers with the addition of placing the propellers on the motors upside down.

Table 2. Thrust Test 3

Testing Conclusions

Motor was barely warm to the touch after running each test.
- Needed no cooldown time unlike thrust test 1.
Battery started at an approximate average of 4165mV and ended at 3980mV.
The motor produced a maximum thrust of 354g during trial 1 of the 6x5.5 propeller.

Garage Test 2

This test was performed with the new lower fuselage, which features a joined front landing gear placed closer to the leading edge of the wing than the previous design.

Test Conclusions

This test worked well, leading me to believe the center of gravity of the previous attempt was causing the plane to swing outwards and turn.

The new design still has remnants of the problem but can be corrected during take off by yawing with the rudder.

Garage Test 2

This test was performed with the new lower fuselage, which features a joined front landing gear placed closer to the leading edge of the wing than the previous design.

Test Conclusions

This test worked well, leading me to believe the center of gravity of the previous attempt was causing the plane to swing outwards and turn.

The new design still has remnants of the problem but can be corrected during take off by yawing with the rudder.

Flight Test 1

This first test will be dedicated to practicing take off and potentially getting the plane up in the air.

If the plane does manage to take off, the next steps are to:

pitch up and down.
yaw left and right.
roll left and right.

The takeoff weight is exactly 500g.

Test Conclusions

The test did not go well.

After 4 attempts at driving the plane in a straight line on the ground, the plane skidded off into the dirt and the bolt holding the empennage to the fuselage went straight through. Additionally, the front left wheel broke off at the axle. Pictures of the breaks shown below

On the last attempt however, the plane went the furthest it had ever gone while following a mostly straight path.

Flight Test 2

This second test will test the new empennage as well as try to take off.

The new empennage features a 35% infill as well as an increased wall count at the fuselage mating surface.

Test Conclusions

After 2 attempted takeoffs, where the plane drove in almost a perfectly straight line for 12 meters. The fuselage started to have problems.

While driving the plane on the ground, the wheels started to splay outwards as a result of landing gear delamination, or layer separation, as well as fractures between the landing gear and the fuselage. This caused the fuselage to sink downwards and the propeller to touch the ground.

Note that the test was conducted on the street, which seems to be too harsh of a surface for the assembly.

Flight Test 3

This third test will feature the new lower fuselage.

This fuselage has the landing gear at 33% wider and 25% longer as well as a crossbar between attached to the bottom of the fuselage.

Additionally, the radius of the front wheels is up from 23mm to 25mm.

Test Conclusions

After a single attempt that lasted 8 meters, the plane once again swerved to the left and caused damage to the lower fuselage - landing gear part.

It seems that I may have to rethink the wheels and landing gear design.

One fix would be to switch the layout of the wheels. By adding two wheels to the aft landing gear and just one to the front landing gear, the plane would start to resemble a commercial plane.