Will Jessop's Writings

Sailing, Food, Programming, Technology, and other things

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| tags:robotics electronics tech

Prototype lifter arm

I added a prototype lifter arm to my robot yesterday. It needs re-doing (it’s unreliable and heavy) but it works for now.

I’m using a new motor driver circuit for it as I burned out the SN754410 motor driver I was using, the lifter motor seems to peak briefly at about 1.5 amps when starting to lift the arm, and that’s out of the chips range. I stayed up late making a new motor control circuit with a L298N that can provide a lot more power.

Here is the robot picking up 12 ping-pong balls. I was driving, Morwenna was filming:

Here is the same run seen through the on-board camera. Almost all of the run was done watching the live feed rather than watching the robot itself:

Here is the paper strip-board design for the L298N circuit.

Designing tHe motor driver circuit for stripboard

Designing tHe motor driver circuit for stripboard

Testing the circuit out on breadboard:

A mess of wires and breadboard and stripboard

Wire everywhere, as often happens when I'm doing electronics projects

A finished circuit on stripbord

The finished circuit. You can see it bolted to the back of the robot in the video.