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personalrobotics / ada_meal_scenario

A set of scripts for a meal serving scenario using Ada.
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Fix loose camera mount #23

Open siddhss5 opened 9 years ago

siddhss5 commented 9 years ago

The camera mount seems to be loose at the base joint. It looks like one of the screws has sheared.

mikedh commented 9 years ago

Hmm, was it during operation or during install?

M1.6 screws are pretty delicate, and only require .34Nm of torque to tighten: http://www.holo-krome.com/pdf/torquedatachart.pdf

Despite this, their nominal load capacity is 283 lbs (https://www.wolframalpha.com/input/?i=%28pi*%281.171mm%2F2%29%5E2%29+*+170000+psi). If it broke during operation it probably means the screw was bending slightly due to the configuration.

If it was on install, it was probably a fastener torque issue. Usually that torque doesn't matter at all, but with tiny stuff like this I would recommend using a torque limiting screwdriver, such as the smallest one of these (28550): http://www.wihatools.com/200seri/285vario_Nm.htm

With a 1.5mm nominal hex bit (73301) or a set: http://www.wihatools.com/700seri/713mmser.htm

to tighten this sort of fastener in the future. Also, you may want to apply a threadlocker (Loctite 222, http://www.mcmaster.com/#1810A27).

Or, a simpler (and possibly parallel) solution would be to epoxy the bracket to the structure.io, and only remove the sensor using the larger M2 screws on the bottom of the bracket. This is probably the easiest way to resolve the issue. I'll take a look at it.