Lesson test: Roll, pitch, yaw, and the mixer

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Roll, pitch, yaw, and the mixer

1.[1p]
To make a quadcopter climb straight up without tilting, the mixer should

increase all four motor speeds equally

Correct

increase the two front motors only

The answer is: increase all four motor speeds equally

increase the clockwise pair and decrease the counter-clockwise pair

The answer is: increase all four motor speeds equally

increase one diagonal pair only

The answer is: increase all four motor speeds equally

2.[2p]
Yaw is commanded by unbalancing the reaction torques rather than the thrusts, which is why

yaw is the weakest and slowest of the three rotations

Correct

yaw also changes the craft's height

The answer is: yaw is the weakest and slowest of the three rotations

yaw requires a separate tail rotor

The answer is: yaw is the weakest and slowest of the three rotations

yaw cannot be commanded while hovering

The answer is: yaw is the weakest and slowest of the three rotations

3.[2p]
A pure roll command adds thrust to one side and removes an equal amount from the other, so the total thrust and the height are barely changed.

True

Correct

False

The answer is: True

4.[2p]
A quadcopter hovers with all motors at 1500 on a 1000 to 2000 scale. The pilot commands a nose-down pitch of 120 units and nothing else. What value do the two rear motors take?

CorrectNot quite: 1620

5.[2p]
Motor saturation limits a quadcopter's control authority most severely when

it is flying near full throttle, leaving no headroom to add for a rotation

Correct

it is hovering at half throttle

The answer is: it is flying near full throttle, leaving no headroom to add for a rotation

the battery is fully charged

The answer is: it is flying near full throttle, leaving no headroom to add for a rotation

all four motors are spinning at equal speed

The answer is: it is flying near full throttle, leaving no headroom to add for a rotation

6.[2p]
The mixer alone cannot keep a quadcopter level because

it applies fixed arithmetic and has no measurement of the craft's actual attitude

Correct

it cannot command all four motors at once

The answer is: it applies fixed arithmetic and has no measurement of the craft's actual attitude

it only controls throttle and yaw

The answer is: it applies fixed arithmetic and has no measurement of the craft's actual attitude

it changes its sign pattern in flight

The answer is: it applies fixed arithmetic and has no measurement of the craft's actual attitude

7.[3p]
Match each pilot command to how the mixer produces it.

Throttle
Pitch
Roll
Yaw

speed one side and slow the other
speed one spin direction and slow the other
speed the rear pair and slow the front pair
raise all four motors equally

Show the answer

Throttle: raise all four motors equally Pitch: speed the rear pair and slow the front pair Roll: speed one side and slow the other Yaw: speed one spin direction and slow the other

1.[1p] To make a quadcopter climb straight up without tilting, the mixer should

2.[2p] Yaw is commanded by unbalancing the reaction torques rather than the thrusts, which is why

3.[2p] A pure roll command adds thrust to one side and removes an equal amount from the other, so the total thrust and the height are barely changed.

4.[2p] A quadcopter hovers with all motors at 1500 on a 1000 to 2000 scale. The pilot commands a nose-down pitch of 120 units and nothing else. What value do the two rear motors take?

5.[2p] Motor saturation limits a quadcopter's control authority most severely when

6.[2p] The mixer alone cannot keep a quadcopter level because

7.[3p] Match each pilot command to how the mixer produces it.

1.[1p]
To make a quadcopter climb straight up without tilting, the mixer should

2.[2p]
Yaw is commanded by unbalancing the reaction torques rather than the thrusts, which is why

3.[2p]
A pure roll command adds thrust to one side and removes an equal amount from the other, so the total thrust and the height are barely changed.

4.[2p]
A quadcopter hovers with all motors at 1500 on a 1000 to 2000 scale. The pilot commands a nose-down pitch of 120 units and nothing else. What value do the two rear motors take?

5.[2p]
Motor saturation limits a quadcopter's control authority most severely when

6.[2p]
The mixer alone cannot keep a quadcopter level because

7.[3p]
Match each pilot command to how the mixer produces it.