PDA

View Full Version : Choosing the right material for robot skeleton/chassis



PeterOeC
02-20-2016, 11:48 AM
Hey forum.

I'm new to building robots, and I need to know from someone with experience.

I want to build a basic bluetooth-controlled driving robot build on Arduino or Raspberry Pi, with wheels, motor, and different kind of sensors.
Basically a RC car that I can put more sensors on step wise as I go. :-)
The length of it could be from 20 cm up to one meter.

What are the skeleton/chassis of a rover/wheel based robot typically made from?
I've heard of some people using balsa wood, others aluminum, and others plastic.

I do not own a 3D printer.

It would be nice if the material has the following properties (prioritized):
- Reconfigurable (To be able to mount sensors on it, and take them off or replace them. This might not be cheap...)
- If it is not reconfiguable it would be nice if it's cheap.
- Lightweight so the wheels does not break and so the moter can push it forward.

Which materials does people use for robots of this type in the beginning?
Could you suggest some different materials and a list pros and cons of each?

Thank you in advance! :)

jwatte
02-20-2016, 06:43 PM
The easiest thing to do is to buy an existing chassis. The Dagu Wild Thumper for example is easy to build on (has lots of holes etc,) comes with the necessary motors/wheels/suspension, and uses "tank steering" which is the easiest to work with.

A lot of people also buy an R/C car, remove the decorative top, and then start adding things to it. This works better with the bigger, more "modular" R/C cars; the smaller, cheaper, cars are sometimes a bit too much "all in one" to allow for easy modding.

tician
02-20-2016, 07:35 PM
The trossen shop sells their rather nice RobotGeek plate system for assorted robot designs which makes it very easily reconfigured just like pegboard and optical tables. Servocity sells an aluminum channel system with lots of mounting and mechanical accessories. A cheap plastic cutting board can work in a pinch, and building a robot in and/or around some sort of cheap enclosure (like a plastic storage bin/container with or without additional mechanical support) can be nice for beginners since it keeps everything well contained and fairly well protected.

Plastics and wood (hardboard, pegboard, plywood, etc.) tend to be cheap and easily modified, but not always quite as robust as metals. Aluminum angle and pop rivets (blind rivets) can be very lightweight and very durable, and everything needed is pretty much always available at big box stores (6063 aluminum angle, drills, rivets, and rivet tool). Steel tends to be a bit difficult unless you have easy access to a machine shop with cutting and welding tools, and definitely overkill unless you are building a combot.



I've actually become rather tempted to build a chassis from aluminum tube/angle and hardboard to hold a small tower of 6qt and/or 15qt sterlite latching containers that have bulk packs on clearance at the nearby target right now. I'm thinking each level a piece of hardboard with aluminum angle to make a rim and large enough to hold either one 15qt container or two 6qt containers side-by-side. I've now got at least 20 of the 6qt containers for holding/sorting my electronics parts and projects on a wire shelving unit, along with several 15qt and 30qt containers for holding larger items like motors, my 20Ah 4S LiFePO4 battery, big protoboards, and larger collections of electronics, connectors, and cables. I can finally see the floor in the corner of the room!

jwatte
02-20-2016, 08:41 PM
Yes: It all depends on budget!

If you're a total newcomer, perhaps the first project you could work your way through would be the $50 robot. It won't actually be a chassis you can then build further on, but it will build invaluable skills and you will learn more about what you will need in the next step.

Link: http://www.societyofrobots.com/step_by_step_robot.shtml