I intend to buy the AL5D PLTW kit, but I want it to be able to handle heavier loads than normal, including having a camera mounted on the wrist armature, so:
Can you include (for a price, of course) 4 extra springs, to attach as I deem necessary to counter the extra weight?
In addition to the heavy-duty wrist servo upgrade, I’d like to have stronger servos for the shoulder and elbow; is that practicable?
Do you foresee any problems with this plan? If so, do you have any suggestions to prevent/solve them?
Unfortunately a stronger servo for the shoulder is not available. The bracket is made specifically for the Hitec 805 servo. Alternatives include:
Metal gears, but no increased torque: robotshop.com/en/hs-805mg-g … motor.html
Digital, but no increased torque: robotshop.com/en/hs-5805mg- … motor.html
We have not tried compatibility with other servos.
As for the elbow, it’s made to be used with the 755, which is also compatible with the 5745MG (no longer available).
The arm includes the 755BB, but you can upgrade to the metal gear version (no added torque though): robotshop.com/en/hitec-hs755mg-servo.html
Don’t reach the arm out to far - the arm is not intended to carry much load, nor be operated for extended periods - it’s “hobby grade”.
The greatest change you can do would be to reduce the lengths between sections, in order to reduce the torque.
You might consider shortening the tube between the elbow and the wrist so there’s less torque on the shoulder and elbow servos: robotshop.com/en/lynxmotion … at-01.html robotshop.com/en/lynxmotion … holes.html
The idea of using an extra pair of springs will help a bit, but they might interfere with each other physically- never tried. You might want to use a standoff to keep them separated.
You might want to instead add a counterweight to the opposite side of the 805 (shoulder) bracket which offsets the weight of the arm. This would be entirely custom.
The heavy duty wrist rotate is strong, but adds weight.
Don’t push the arm too far the first few times - get a sense of the load it can handle. It’s easy to burn servos since they have no built-in protection.
Thanks for your quick and very helpful reply, Mr. Benson! Shortening the arm sections is on the “if necessary” list. So are counter weights, as they would put extra strain on the servos during high-speed acceleration (including change of direction). Still good suggestions, as such mods are easily un-doable if they don’t work out for some reason. As for upgrading the 3 servos ( wrist rotate and 2 MG versions): when I order the AL5D PLTW kit, would I be paying the difference in the cost of the servos, or do I need to order the 3 servos in addition to the ones that come with the kit?
As always, double check to ensure it includes all you need. Ordering a few spare Lynxmotion brackets which are SES compatible now might save you shipping later.
