- #1
Home Improvement
Hi,
The goal here is to increase/decrease the angle x by 5 degrees. the black circles represent a rubber tire (same as car tires, only smaller), 5cm in diameter, rotating on it's center, powered by a motor. each wheel has 40 psi (2.76 bar) of air in it. the yellow tray on both diagrams are identical, weighing around 20kg and 2m long and 4cm wide. weight (m) on both diagrams are also identical, weighing 200kg, welded shut to the yellow tray.
my questions is I need the formula to calculate the following:
1. in the top diagram, assume front and rear wheels are treading on asphalt surface, so rolling coefficient is around 0.0087. I got this number from https://www.engineeringtoolbox.com/rolling-friction-resistance-d_1303.html. what is the total energy the motor of rear wheel need to exert to move the system from a complete standstill until the increase angle x by 5 degrees?
2. also in the top diagram, I assume the amount of energy exerted would exactly be the same if it's only the front wheel motor that moves?
3. in the bottom diagram, the wheel axis is exactly in the middle of both the weight and the tray. I assume that if x is below 45 degrees, gravity will handle decreasing the angle (motor needs not exert energy to decrease x). the same also applies when angle is above 45 degrees and we want to increase x. if previous assumptions are correct, how much energy does the motor need to exert to decrease x by 5 degrees (when x is greater than 45)? what about increasing x by 5 degrees (when x is less than 45)?
4. for top diagram, I assume we can just rely on gravity if we want to decrease x by 5 degrees? provided that x is not 90 degrees.
thanks
The goal here is to increase/decrease the angle x by 5 degrees. the black circles represent a rubber tire (same as car tires, only smaller), 5cm in diameter, rotating on it's center, powered by a motor. each wheel has 40 psi (2.76 bar) of air in it. the yellow tray on both diagrams are identical, weighing around 20kg and 2m long and 4cm wide. weight (m) on both diagrams are also identical, weighing 200kg, welded shut to the yellow tray.
my questions is I need the formula to calculate the following:
1. in the top diagram, assume front and rear wheels are treading on asphalt surface, so rolling coefficient is around 0.0087. I got this number from https://www.engineeringtoolbox.com/rolling-friction-resistance-d_1303.html. what is the total energy the motor of rear wheel need to exert to move the system from a complete standstill until the increase angle x by 5 degrees?
2. also in the top diagram, I assume the amount of energy exerted would exactly be the same if it's only the front wheel motor that moves?
3. in the bottom diagram, the wheel axis is exactly in the middle of both the weight and the tray. I assume that if x is below 45 degrees, gravity will handle decreasing the angle (motor needs not exert energy to decrease x). the same also applies when angle is above 45 degrees and we want to increase x. if previous assumptions are correct, how much energy does the motor need to exert to decrease x by 5 degrees (when x is greater than 45)? what about increasing x by 5 degrees (when x is less than 45)?
4. for top diagram, I assume we can just rely on gravity if we want to decrease x by 5 degrees? provided that x is not 90 degrees.
thanks
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