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Unread 28-04-2009, 15:14
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AKA: Martin Wilson
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Re: Winning Drive Train

Quote:
Originally Posted by JVN View Post
Anybody have anything quantitative to share? Anybody? Anybody? Bueller?
Here is the data we took on our bot. We were using follower wheel traction control limiting the slip ratio to ~.2. The drawbar pull was measured using a fish scale (hand held) with both joysticks firewalled, while allowing the bot to slowly travel forward over the regolith. With just the wheels, we got around 18-20 lb.f on average. If we turned on the propeller propusion, we got 26-28 lb.f.

I won't say we got 8-10 lb. thrust from the props, I am guessing there were other factors involved. The voltage drop due to the propellers running may have made the traction control work better, or the airflow may have blown away the regolith dust as it was produced, increasing traction. I don't know. I am just reporting the raw numbers.
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