## Forum Posts

Sören Schröder

Mar 23, 2022

In Make your own FlowIO

Which shore A value should the silicone have used for casting valve plugs?

0

1

14

Sören Schröder

Mar 21, 2022

In Make your own FlowIO

Hi everyone :) We are looking for fitting batteries. We found an offer with the required size and capacity. Still, the distributor warns that the batteries are not suitable as a battery for motor-driven models. They state that the battery can handle a continuous discharge current of 0.5C (which I learned today correspond to discharge of 250 mA over 1 hour for the suggested 500 mAh battery). The maximum discharge current is stated with 2C for 10 seconds. I then checked what the battery usage of the components would sum up to. We bought the S070M-RCG-40, powered at 3VDC and rated with 0.5 W power consumption. If I haven't made a mistake, this results in ~167 mA per valve. For a fully equipped FlowIO device (7 valves) this would results in 7 * 0,167 A = ~1,17 A. This seems quite a lot to me and definitely exceeds the 0.5C of the battery. Therefore, my question is if I miscalculated something on the way or if my assumption is correct and the very battery isn't suitable for the FlowIO?

0

2

19

Sören Schröder

Jun 14, 2021

In Make your own FlowIO

For our project, we decided to go with the large pumps. Now we've asked ourselves what are the best fitting valves for them. In the following, I would like to ask some questions related to the calculation of airflow and pressure. On the page of the pump is stated, that they provide a pressure of 130 KPA and an Air Flow of 6 l/min. For the sake of clarification: I use the values from the upper table on the page since the values in the lower image are deviating for some reason. For the valves the C (0.5 W, 0.3 MPa, Cv-factor: 0.016) and D (0.5W, 0.5 MPa, Cv-factor: 0.011) versions are the most interesting. Now I want to know which provides the highest pressure and the highest flow rates. Since the pump only delivers 130 KPA the valves are not the limiting factor and we can say, that 130 KPA is the maximum pressure. In the valve's datasheet in the table of Flow Specifications/Response Times is stated that C (the airflow?) is 0.060 [dm³/(s*bar)] for the C-valves and for 0.042 [dm³/(s*bar)] for the D-valves. Is it now correct to calculate the maximum airflow by using the 130 KPA (= 1.3 bar) from the pump as follows: C: 0.060 * 1.3 bar = 0,0780 dm³ / second
D: 0.042 * 1.3 bar = 0,0546 dm³ / second If these calculations are correct I would assume that the C valves would provide a greater airflow. If I'm messing up things here totally, maybe someone could provide me a good source that helps to understand how to calculate pressure and airflow for a given pump and valve. In all cases, thanks for your help!

0

2

30

Sören Schröder

Jun 14, 2021

In Make your own FlowIO

In the BOM's pneumatics section the intermediate block SS070M is mentioned to be required 4 times. In the Make FlowIO sections, I couldn't find the point where they are used. Can anyone tell me what is the reason to have them? Furthermore, is their amount somehow linked to the number of valves I'm going to use in my FlowIO?
Thanks in advance for your answers :)

0

2

29

Sören Schröder

Jun 08, 2021

In Make your own FlowIO

It appears to me as if the sections 11 (Pump Module Assembly), 14 (Sensors++), and 15 (Expansion Port Breakout) aren't linked to a page, yet. Is this correct and if so, is there an ETA when they are available. Anyway, thanks for the comprehensive documentation can't wait to have a own FlowIO to play around with!

0

2

46

# Sören Schröder

Writer

Followers

Following

Follow

Message

©2022 by Ali Shtarbanov.

Except where noted, this work is licensed under a CC BY-NC-SA 4.0 license.

Commercial use permission can be requested by submitting this form.

Any use of FlowIO or content from this website requires "appropriate attribution" credit under the Creative Commons licensing terms

(attribution example: "FlowIO Platform by Ali Shtarbanov, licensed under CC BY-NC-SA 4.0, from www.softrobotics.io")