Human Force Power

Posture	Action	Maximum Force
Sitting (with backrest)	Horizontal force on a pedal	1000 N
Sitting	Vertical force on a pedal	300 N
Standing	Vertical force on a pedal	500 N
Standing	Repeated action on a vertical lever (pump)	90 - 100 N
Standing	Operating a rotating wheel or crank arm	130 N

Operational Constraints:

For a vertical lever (pump), the frequency should not exceed 20 beats per minute.
For a rotating wheel or crank arm, the wheel speed should not exceed 25 - 30 rpm. The optimal arm length (or wheel radius) is approximately 0.4 m, and the center of the axle should be at a height of approximately 1.0 m.

Power Calculation for Rotating Mechanism

The power output produced by a human applying force to a rotating wheel or crankshaft is given by:

P = \frac{F \cdot r \cdot \pi \cdot n_{rpm}}{30}

Where:

$P$ = Power output ( $W$ )
$F$ = Applied force ( $N$ )
$r$ = Radius of wheel or crank arm ( $m$ )
$\pi$ = Pi (≈ 3.14159)
$n_{rpm}$ = Rotational speed ( $rpm$ )

Example Calculation: Using the ideal conditions for a standing person operating a crank ( $F = 130 \, N$ , $r = 0.4 \, m$ , $n_{rpm} = 25 \, rpm$ ):

P = \frac{130 \cdot 0.4 \cdot \pi \cdot 25}{30} \approx 136 \, W

References

Original Source