Grabber

Let's Make Robots Robots
1

UPDATE : video uploaded . In the video the robot picks up bottle as well as avoids an object which cannot be picked.

It uses 3 sensors i.e. 1 SRF05 and 2 GP2D12 to detect objects and decide whether the object should be picked up or it should be avoided.

GP2D12 were not stable enough so i soldered 50uF capacitors between the ground and Vcc

I used a 10 RPM Dc gear motor for the arm. It gives around 8-9 Kg of torque at 9V

For using this motor i used a  L293D motor driver other than the one in main board and made connections on the breadboard. Since i didn't had any of the digital outputs left i used the digital inputs and converted them to digital outputs for controlling the arm motor

The gripper is homemade 

The three sensors

All the wire mess on its back

Top view

Thanks for your Support !

Picks up objects(bottles) that comes in its way

  • Actuators / output devices: Tamiya twin gearbox, 1 Towerpro MG955 servo and 1 Dc gear motor
  • Control method: Full autonomous
  • CPU: Picaxe 28x1
  • Operating system: windows XP
  • Power source: 4.5 V for the board and 9V for the arm motor
  • Programming language: Picaxe basic
  • Sensors / input devices: 1 SRF05 and 2X Sharp GP2D12
  • Target environment: indoors mainly
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/grabber
2

I like it. Can’t wait to see

I like it. Can’t wait to see a video of it in action!

3

wow! great job

wow! great job

4

thanks phoz

thanks phoz

5

Nice gripper

Where did you get ahold of those plastic gears and how did you fasten them to the servo?

6

i used a small pinion gear

i used a small pinion gear and glued it at the servo output and that pinion gear is geared with one of the large gears

so when i program the servo the pinion gear rotates thus rotating the large gears.

and i bought those plastic gears from a store website in my country…

7

I like the grip!

Hey, nice robot! 

And very good grip. It seems simple but very effective.

Congratulations

 

8

Gear Ratio

"The only problem i have to deal with is that the robot is not turning properly maybe. I think its because of its weight. Anyway i’ll figure it out someday."

Hello, I’ve built a number of bots with these Tamiya duel motor/track setups. They have 3 ratio’s you can set. On my drum robot I had to use the lowest set and replace the motors with these: http://www.pololu.com/catalog/product/604

Just trying to help :wink:

9

Thanks :slight_smile:

Thanks :slight_smile:

10

The manual(page) i got with

The manual(page) i got with tamiya twin gearbox shows that only two gear ratios can be used with it.

its like 58:1 and 203:1.I used 203:1 but still no success…

11

RE

I’m just trying to help :slight_smile:

there’s 2 versions of these gear boxes, one has 3 ratio’s, the other 2.

Either way you can upgrade the motors for more power, the link I sent before are the ones I use.

Solarbotics and Pololu have another version (if your motorcontroller can handle it) thats A LOT more powerful, see the chart http://solarbotics.com/assets/datasheets/592.gif

here’s a link to buy them at http://solarbotics.com/products/rm2/resources/

12

RE RE

PS,

if its not obvious, I like this robot you built.

I wanted a gripper bot, but got lazy and just bought one…(actually bought 3 !!!)

 

13

I live in india so i dont

I live in india so i dont think its worth buying the motors costing 1 to 2 $ and paying for the shipping charges 8 to 10$

anyway i noted down the specs of that motor and will try to find in my country…

thanks for your help.

14

maby

a theory why it is no working is that

as you have not include the other small wheels i think all pressure is going onto the great box which it will not like

you will have to add in the other smaller wheels which will be a pain

this will also reduce the area of the treads touching the ground and their for friction 

this is a theory but i hope it helps

 

15

i appreciate your help. But

i appreciate your help. 

But the reason why i didnt use other small wheels was that i wanted to keep the height of Grabber as low as possible…