PIRANTULA - A powerful hexapod / spider by vodzurk

Last crawled date: 3 years ago

WARNING: THIS ROBOT COULD EASILY CAUSE HARM TO YOURSELF OR OTHERS!
Disclaimer: Only commence making this robot and subsequently use it if you are fully aware of the dangers involved. I bear no responsibility for any harm or damage caused by making or using this robot. This robot is dangerous. Do not proceed to make it unless you fully undertand the danger and are of sufficient skill to avoid harm to yourself or others.
It's like a tarantula... but only 6 legs so not a tarantual... it's PIRANTULA!!
Design intent: Must be badass!
After being frustrated by lightweight robots, my aim was to design a robot with plenty of potential for expansion. To do this, I figured I need powerful servos and power supply.
This robot should be able to carry plenty. It's not the cheapest due to the powerful servos used.
Please take very good care of your fingers. The servos used here could easily snip off your finger. Also beware that it can pack quite a punch if you're in its way (it's drawn my blood already in one accidental "punch"). To keep it as safe as possible to myself, I've added a relay to cut off the servo power remotely via the Pi. Also beware that these power packs can pump out a lot of juice if shorted, which can burn you. I'd recommend removing any metal jewellery whilst building the circuits.
Designed entirely in FreeCAD, I can post up the source files if anybody is interested (typing this+BOM has taken forever!).
Also, as I post this, I've only just finished hooking it up and making it stand... so it's early days yet! Apologies for such crudeness in the design :). I work full time, so only have a few hours a week to improve / update the design... but fully intend to keep doing so :).
Future thoughts?
Upgrading to include ROS (currently using my very amateur Python code).
Single power supply (instead of separate source for Pi).
Adding a detachable module on top for extra Pi4 power, using supply from main unit.
Research into SLAM with pi camera and possibly LiDAR.
Bill of Materials:
18x Servos - Hiwonder LD-220MG Link
1x Pi Zero W - Link
2x Servo Bonnets - Adafruit 16ch PWM bonnet for Pi Link
4x Header pack (right angled) Link
4x header pack (straight) Link
1x 40-pin Extended header Link
1x 40 pin Female header Link
1x extra header pins - for hooking Pi pins onto topmost Servo hat Link
1x 40A 18650 Battery pack Link
1x 40A 18650 Battery pack with BMS Link
1x USB power bank - for powering pi Link
2x Voltmeter/Ammeter Link
~4 5-wire connectors Link
1x 30A relay Link
6x M6 25mm - for attaching legs to body Link
18x M6 40mm - for attaching servo brackets to leg pieces Link
~50 M3 12mm hex bolts - for screwing case lid down Link
12x M3 16mm bolts for screwing case sides together Link
12 m3 nuts
24 M6 nuts
Lots of M6 washers - to give the legs a chance not to snap off, by easing the strain around the M6 bolts.
1x Fuse Holder - In case of things going bad! Link
2x 20A step down modules Link
various brass standoffs Link
Tons of cable ties Link
Various 30A power connectors - Link