Hey kull, for bench power supplies, the easiest solution is to find a higher amperage digital switching supply. Although, I tend to prefer adjustable bench supplies because you can monitor the amperage draw.

The answer to your question regarding how long batteries last is related to the current draw - so it’s impossible for me to answer but you can identify it yourself. If you are serious about your project, a bench adjustable power supply on eBay is a good choice and only costs approximately $100 usd. That will give you the current draw which will help calculate your power consumption.

Because the motors will be holding weight that is specific to your configuration, it’s not as simple as assuming a servo draws X amps. You will have accurate assumptions by monitoring the current while the robot is in use.

Because of the hardware you’ve described, I would configure the adjustable bench supply for 7.4 volts

If your robot is drawing 1 amp continuously, and you want it to run for 4 hours, you’d need a 4 amp battery. The batteries you will find have an amp hour rating. That’s how many amps of current it provides in an hour.

Wow here’s one for $10

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.ca%2Fulk%2Fitm%2F323817738170

10 amps are ideal

Man! I'd be afraid to plug that one in. How can they sell this for that cheap?? I may just have to get one and try it out. Carefully and under a close watch. LOL.

OK, I pulled the trigger and bought one. Price for mw with shipping was just under 9 USD. We'll see but how can I go wrong with a digital display and the ability to adjust from 0 - 30 volts and it will stand up to 10 amps. Heck, if I accidentally send more than 10 amps through it and fry it, the smoke show will be worth at least the $9 I spent. LOL.

However I'll have to wait up to 28 days for it to arrive. I guess this what they mean when they say "Slow Boat From China". LOL

Thanks for the heads up DJ!

Lol that’s amazing. I thought of getting one to just to see. Jeremie and I have similar ones that cost 10 times more and work great. The hardest part is finding 10 amp versions like that.

I just purchased one, the cost of 3..99 shipping was almost the cost of the bench power supply,  we will see in a couple of months.

Haha see - maybe these guys are actually making a bit of money because so many people are buying it at this price. It wouldn't cost much less than the asking price to manufacturer the product in high quantity... specifically since the product has been on the market for a number of years and the cost of r&d has been covered long ago

.... or, they light on fire and burst into flames when we turn it on

Quote:

or, they light on fire and burst into flames when we turn it on