Vex Pneumatic Shot Calculation vs P_regulation

 How many shots are available vs the regulation pressure , p_ref?Data applies to Vex Pneumatic piston kit, double acting cylinder.  
p_ref_psig   psig Regulated pressure
A_push 0.12 in^2 Piston area push   
A_pull 0.1 in^2 Piston area pull  
stroke 2 in Full stroke = 2 inches
n_actuators 1   Number of actuators required at p_ref selected
n_tanks 1   Number of resevoir tanks available
l_tube 8 in total tubing length between regulator output and piston (include width of solenoid path as tubing)
d_v_tube 0.10 in^3  =PI()*0.125^2/4*l_tube
V_tank 9.15 in^3 Resevoir Tank volume (ignores the tubing on upside of regulator)
p_tank_g 100 psig Initial tank pressure (guage)
Volumes lost with each piston actuation , nominal stroke 2 in + .8in end gap
d_v_push=(A_push*(stroke+ 0.8)+ d_v_tube)*n_actuators*(1-14.7/(p_ref_psig+14.7))
d_v_pull=(A_pull*(stroke+ 0.8)+ d_v_tube)*n_actuators*(1-14.7/(p_ref_psig+14.7))
V_tank_p_ref=V_tank*(p_tank_g+14.7)/(p_ref_g+14.7)    
V_avail=V_tank_p_ref-V_tank   Avail air volume at p_ref
 N_shots=V_avail/d_v          
           
                p_ref_ psig    N_shots pull      N_shots_push     N_cycles    
80 6 5 3    
75 8 7 4    
70 10 9 5    
65 13 11 6    
60 16 14 8    
55 20 17 9    
50 24 21 11    
45 30 26 14    
40 36 32 17    
35 45 39 21    
30 56 49 26    
25 73 63 34    
20 97 84 45    

To estimate effect of different number of actuators and tanks multiply the N_shots given in table by N_tanks/N_actuators.

Advertisements

One Response to Vex Pneumatic Shot Calculation vs P_regulation

  1. Great website you have here but I was curious if you knew of any user discussion forums that cover the same topics discussed
    here? I’d really love to be a part of community where
    I can get responses from other experienced individuals that
    share the same interest. If you have any
    recommendations, please let me know. Appreciate
    it!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: