Delivering Power to Jetson on Robot


#1

Today, our team finally got our Jetson TX1! However, a team member brought up the question of how to power it. Considering the power adaptor it comes with is rated for 19V, my question is how do teams deliver power to the Jetsons on their robots?


#2

We used this all last year: https://www.amazon.com/RioRand-Converter-Voltage-Adjustable-Circuit/dp/B071H39ZN5/

Wire in 12VDC from the PDP, attach a multimeter to the output pins on the regulator, twist the potentiometer until you get roughly 19V (the dev board doesn’t actually need this high a voltage, pretty sure it’s on board regulators can take down to 12V). The wire up a barrel jack that can plug into the TX1. You’ll want to mount it on your robot in a way that ensures it cannot contact other electrical components or metal (3d print a case, Velcro on back, double side tape on back, etc).

Note the one we used was not from this seller, and there are plenty of comparable boost converters that will work in this application from alternate sites (eBay, AliExpress, etc)

Try to stay toward higher current ratings as the advertised specs aren’t always accurate on these cheapy boost converters, and the tegra can draw a few amps if I remember correctly. Take a look at the AC adapter it came with for the current rating. If I remember correctly our application didn’t break 2A at ~19VDC, but power usage will be completely dependant on what your vision code is doing.


#3

We tried your solution with the voltage adapter, but our Jetson will not power on. We have tested multiple ranges between 19 and 24 volts and while the red light comes on, the Jetson will not power. We have wired the voltage amplifier to a 20 amp port on the PDP. Is there anything we are missing here?

Thanks!


#4

My team has used a buck converter to get constant voltage to the Jetson.


#5

Am I missing something? The TX1! input voltage range is specified at 5-19 volts. You should be able to wire directly to the 12 volt output of the VRM and get the voltage stability of the VRM.


#6

No need this year the rules specifically allow the use of batteries in certain situations, and i believe this would qualify, so why use a slot on your vrm when you can use a battery solely dedicated for the Jetson.


#7

Sounds like you need some…

Jet fuel


#8

We tried this but atleast with the default carrier board (may change with others), it needs like 14 (higher than VRM provides) volts to start, then can operate on less.


#9

Is this the battery you are thinking of?

R40. COTS USB battery packs with a capacity of 100Wh or less (20000mAh at 5V) and 2.5 Amp max output per port, or batteries integral to and part of a COTS computing device or self-contained camera (e.g. laptop batteries, GoPro style camera, etc.) may be used to power COTS computing devices and any peripheral COTS input or output devices connected to the COTS computing device provided they are:
A. securely fastened to the ROBOT.
B. connected only using unmodified COTS cables
C. charged according to manufacturer recommendations


#10

Can you provide details on what “voltage adapter” you’re using? Maybe pictures/video? A link to the specific boost regulator you purchased? It’s possible it can’t supply enough current to the TX1.
The TX1 board does boot up when using the wall adapter right?
If so, then it’s either the voltage is too low, or boost regulator can’t supply enough current at the set output voltage to satisfy what the TX1 needs to power on.

Can you wire in a multimeter across the power input pins and verify the voltage being supplied isn’t dipping out when the supply is put under load (power button pressed)?
If you do see a voltage drop, then that’s probably the problem. A big capacitor across the power output from the boost regulator may be able to get you over the hump during startup, but if that proves to be the cause (voltage dips under high load) the boost regulator is either underrated for the job or defective and likely isn’t a good candidate to run the whole season on.


#11

I think the issue is that the VRM can only deliver 2A (24W). I̶ ̶k̶n̶o̶w̶ ̶t̶h̶e̶ ̶T̶X̶2̶ ̶d̶r̶a̶w̶s̶ ̶u̶p̶ ̶t̶o̶ ̶9̶0̶W̶ (plain wrong, see below); I’m sure the TX1 is high as well. Also, some people recommend only running only the radio from the VRM.

Towards the original question, team 900 recommends a certain converter available which you can find in their whitepaper or suggested by Marshall around CD.


#12

I haven’t a clue where you are getting the 90W number from. Typical power draw for the TX2 is like 10W or less (I think max is like 14?).

Either way, this is the adapter we’ve been recommending for a while now:

Buck Boost Converter, DROK DC 5-32V to DC 1.25-20V 60W Constant Voltage Current Volt Regulator Module - https://www.amazon.com/dp/B00JKG57T4/ref=cm_sw_em_r_mt_dp_U_xJgtCb6CWJ7XK

If you want more info or we can help then reach out to support@team900.org. We’re happy to help support teams using the Jetson however we can.


#13

Sorry the 90W number was for the carrier board that we have that was in FIRST choice two years ago (still that is high and only if a lot of peripherals are plugged in), or maybe just the max the provided AC adapter could deliver. It’s just wrong.


#14

The TX1! was the device we were talking about and the current can be high if you use a lot of peripherals powered from the kit like USB, SATA drives, etc. Since the discussion is about vision processing, current should not be that high.

On another subject, I do not recommend using the VRM that powers the radio for any other purpose. Just my head tellimg me that I don’t want any other device failing as a cause to taking out the radio power supply. I know it is a little cost to add another VRM but I want to play above all else. If vision processing dies but my team can still drive, we still have a chance.


#15

I second this notion of only powering the radio with the VRM. You’re taking a risk using it to power anything but the radio alone. Get another regulator and use it for custom circuits, LEDs, vision systems, Jetson, Pis, etc…