2 FESTO valves on 1 spike

[bhsrobotics1671]

does anyone know if its legal or even possible (without the fuse tripping) to connect to FESTO valves to one spike. they are each out puting to one cylindar, on our arm the is a mirror image on both sides.

we are just trying to reduce the amount of spikes that we are using and are wondering if FIRST, or our current, will allow it.


thanks!

[seanl]

why dont you just put a T on the pneumatic tubing and run it to the two cylinders thats what we did. and less weight from the extra festo.

[Chaos204]

is there a reason that you are not putting a T splitter on one festo? I don't have much experience with festos specifically but the regular valves work with one valve with a T split

[adamm]

I'm also on team #1671.

We are using 2 values becuase we need fast airflow. From what I've been told 2 festo valules will allow faster airflow than 1 with a T. Also, with the T adapter, one piston could take more of the airflow if the other has more resistance on it. We need them to move equally at the same time.

We are mainly curious as to how much draw the values have when in use.

I will try to see if the T is a valid option on our robot.

[MrForbes]

The Festo valves have very low current draw compared to what a Spike can supply, so you need not be concerned about it for that reason. Just make sure to carefully read the rules and see if it is allowed! also I would think that having both cylinders connected to the same tube with a T would be the best way to balance the air pressure between them. However, that won't guarantee that they will move at the same rate.

[Brad Voracek]

We are planning on running 2 spikes (y-cable'd together) to 2 valves, then have a system to make sure they run around the same, but still with the increased airflow.

Our system looks something like this:

http://img266.imageshack.us/img266/601/flowms7.jpg

... we ran a spike on each for some reason I don't know. Probably because our team thought it was illegal to run 2 off of one. ;P

[Al Skierkiewicz]

Andrew,
This is the rule that addresses your question.

<R56> Each power regulating device (Victor speed controller or Spike relay) shall control one and
only one electrical load (motor, actuator or compressor). Multiple low-load devices (e.g.
pneumatic valves) may be connected to relay modules (but only one motor may be
connected to each relay module).

[Mr. Lim]

It is possible to connect two single solenoids to a single Spike, and control them independently. See here for the wiring diagram: http://www.ifirobotics.com/docs/spik...uide-sep05.pdf on page 2.

Please note that this has been a legal setup in the past, but rules from prior years do not apply to this year. I can't comment on the legality at this time, and your best bet will be to ask the official Q&A.

FYI, using the referenced setup above, you'll quickly discover that you can actually run a Spike relay in both forward and reverse at the same time. This brings both output pins high to 12V, which would activate both solenoids simultaneously.

[HUNT397]

If we take four festo's and put them in parell with one another using a terminal and fire them with one spike would that be legal? If it is described in (r56) can someone please clairify.

[Daniel_LaFleur]

Originally Posted by adamm

I'm also on team #1671.

We are using 2 values becuase we need fast airflow. From what I've been told 2 festo valules will allow faster airflow than 1 with a T. Also, with the T adapter, one piston could take more of the airflow if the other has more resistance on it. We need them to move equally at the same time.

We are mainly curious as to how much draw the values have when in use.

I will try to see if the T is a valid option on our robot.

While the combined flow rate of 2 Festo valves is more than 1:

Norgen regulators have a 14 SCFM flow rate.
Festo valves have a 14 SCFM dlow rate.
Thus, unless you put some of the clippard volume chambers downstream of the regulator, running 2 Festo valves will produce a slower cylinder response than just 1 Festo valve (I know ... we tried it).

Also "T"s add restriction by creating non-laminar flow, which will reduce the flow in the system.

[GBIT]

Originally Posted by Daniel_LaFleur

While the combined flow rate of 2 Festo valves is more than 1:

Norgen regulators have a 14 SCFM flow rate.
Festo valves have a 14 SCFM dlow rate.
Thus, unless you put some of the clippard volume chambers downstream of the regulator, running 2 Festo valves will produce a slower cylinder response than just 1 Festo valve (I know ... we tried it).

Also "T"s add restriction by creating non-laminar flow, which will reduce the flow in the system.

your actually better off using one solenoid and putting a "Y" joing in line to the two cylinders. It keeps the system more linear. and if you are really looking for a lot of air flow try the FESTO tiger valves. They used to be supplied in the kit so they are legal. The festo valve moves about 300 liters a minute i believe and the tiger valve moves about 1100 i believe i was told.

but depending on your bore size it should move fast enough to do what ever you want it to with just one of the new festo valves.

[HUNT397]

Back to the origional question. Can multiple festo valves be ran off of one spike? Rule 56 appears to say yes. What do you think?

<R56> Each power regulating device (Victor speed controller or Spike relay) shall control one and
only one electrical load (motor, actuator or compressor). Multiple low-load devices (e.g.
pneumatic valves) may be connected to relay modules (but only one motor may be
connected to each relay module).

[Vikesrock]

Originally Posted by HUNT397

Back to the origional question. Can multiple festo valves be ran off of one spike? Rule 56 appears to say yes. What do you think?

<R56> Each power regulating device (Victor speed controller or Spike relay) shall control one and
only one electrical load (motor, actuator or compressor). Multiple low-load devices (e.g.
pneumatic valves) may be connected to relay modules (but only one motor may be
connected to each relay module).

This is addressed directly by the rule you have quoted as well as the Q&A in multiple responses. Multiple valves may be run off of the same spike.