Following the infomation provided by Leo van Miert, it has been agreed that the limit of 6 cells per pack will be increased to 7 cells.
The post above has been amemded accordingly and we thank Leo for his input.
Fighting Robot Association.
Following the infomation provided by Leo van Miert, it has been agreed that the limit of 6 cells per pack will be increased to 7 cells.
The post above has been amemded accordingly and we thank Leo for his input.
Fighting Robot Association.
If the use of CO2 becomes an enviromental issue in the future then the FRA will be happy to look at the use of other gases.
However, I will point out now, that the CO2 our robots use is not generated in the same manner that the effects of combustion generate. The CO2 is pulled from the atmosphere, compressed and piped into cylinders. We then release the CO2 back to the atmosphere. The overall cost is zero.
As an ex-employee of a major gas company (Messer aka Loxhydrique aka Messer Griesheim) I can garantuee you that CO2 is not just won from Air splitting plants because that is a very expensive process. It is however usually the bi-product of another process, therefore the process of CO2 production is not costing more than it would just dumping it into the air apart from the inital investment of a filling station and maintenance.
Andy said something about decanting, be advised that CO2 decanting as its done at events is absolutely a no-no. liquid CO2 has an even bigger disadvantage, there is more co2 in a liquid co2 bottle than there is HPA/Nitrogen in a 200 bar bottle of the same size. So eventough the HPA bottle would be way more violent in the beginning, it will die down a lot faster than a CO2 bottle does in the same situation. Ive seen both events happen in more than one occasion at work, and in both situations the only thing you can do is stay as far away from the bottle as possible. The main advantage to HPA/Nitrogen is however that you can fill on pressure, which means you dont have to take the bottles out of the robots to weigh them which means they are always in a safer enviroument tied down in the robot. For good measure you really should do the same for CO2.
Inside the robot is not 200 bar of pressure, it is 70Bar max, so in effect a robot using HPA/N2 is in fact carring less gass than a CO2 robot would unless it puts in more/bigger bottles. Blow for blow CO2 is more of an advantage to roboteers, however dont kid your self that we dont pollute the enviroment, we are, if only by charging batteries. How much we pollute is a matter of interpretation.
Maximum of seven cell packs with proprietary chargers and balancers.
I have two questions regarding this line.
- Is the 7 cell limit ment for voltage? If so, this could mean I can have a 7 cells in series and 2 in parallel (14 cells in total) in the same pack?
- Define proprietary. Would a deWalt pack with 10 cells be allowed? Would a system I design for my company not be allowed? If not, can I make an open source version so it will be allowed?
Currently the FRA are allowing 7 cells per pack. As Lithium requires that the cells are not charged in parallel you should not assemble the packs in parallel. You could use 2 packs of 7 cells each to improve the current discharge characteristics.
The charging process requires care, particularly when the batteries are used for high current applications. The DeWalt charger does not balance the cells sufficiently for this purpose.
Currently it appears that the biggest effect of poorly balanced batteries is the potential for overcharge which with the A123s seems no worse than a NiCd fire. Although the cost to the roboteer is much greater.
This isnt a closed subject and the FRA will be happy to expand on this once the technology is available.
Im sorry this is turning into a technical discussion again. If a forum admin feels free to move this part to the other thread, please do so.
I understand why in theory it might be a problem to put lithium cells in parrallel, but the same problem would affect discharging several packs in parallel, although you might have a slightly larger resistance in the connectors to counteract any voltage differences.
However, we work with a proffesional battery-pack manufacturer who is perfectly happy to put a123s in parallel. They have done so on several occations.
As for cell balancing, ive seen the issues you mention aswell. How does a 7 cell-limit help to avoid these situations?
Apart from this, the proprietary issue is still a little too vague for my taste.
quote:
D. Rewrite of rule 6.3.2 link rule. For certain machines there will be a requirement for a second link. ( this affects very few machines )
What kind of machines would require this?
The finer details will be published at a later date, but basically an invertable robot like a spinner where you cant get to the main link to disarm it if it is upside down and the robot has no way of flipping itself over.
I see. That makes perfect sense. Thnx.
When are we going to see the detailed minutes? I know there is one point that is very much time critical.
3. Proposal to bring the heavyweight weight to 100KG including consumables(gas)
The Governing body concluded that the proposal had merit as it would tie in with the new featherweight ruling and give a world common standard for weights.
How ever it was decided to go to the membership for consultation first either by written submission via the members regional chairperson( FRA forum contact page) or info@fightingrobots.co.uk
Consultation period to end 31/12/2007
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