The previous post dealt with the working of the embedded team in the Summer of FIRA – Moving on, the next team is the Mechanical Team. While the embedded team dealt with circuits and implementing PID this summer, the Mechanical Team focused on the CAD design of the bot and the optimization on a hardware level. CAD stands for Computer Aided Design which refers to using a computer to design the body of the robot which is then manufactured at a manufacturing unit.
The aim of the CAD design is to make a feasible design – which meets the requirements of the competition and also is feasible to manufacture and, mechanically correct. The bot should be able to withstand the various forces it might encounter and must be sturdy.
Also, with enough simulation demanded, especially considering the biggest challenge of the space constraint involved, CAD is the best way to virtually build the mechanical aspect of the bot without rushing off to the manufacturing center.
The summer of FIRA saw the mechanical team working for both the FIRA and the Robocup competitions. Prior to the summers, the design for the FIRA bots was almost ready. The robots were manufactured for FIRA by CWISS, IIT Kharagpur using aluminium as the body metal. The bot was given a double – grooved structure to hold on to the ball during the match. The final product was a replica of the CAD design that was made and this is where the advantage of CAD kicks in.
The new design was completely designed and manufactured by KRSSG – with complete customization on the grooves. Also, with aluminium, which was a development from previously used Perspex glass, the bots are sturdier and more suited to the football games. The grooves are provided on both sides of the bot which allow it to handle the ball from both sides, an additional capability of the bots.
Apart from FIRA, the Mechanical Team also worked on the Robocup designs as the CAD Designs for the FIRA bots were established and the bots had been manufactured.
The design began with the notion of a 3 wheeled bot with bulky motors, and simple kicker-dribbler mechanism. However, over the summers, the mechanical team has extensively developed on the Robocup bots. The 3 wheeled bots were replaced by the 4 wheeled bots. Riding high on innovation, the team also floated and implemented the idea of an angular kicker, which allowed the new Robocup bots to kick at any angle without turning along with the conventional chip kicker and dribbler mechanism. This work is in the development phase and will be tried and tested for the Robocup competition.
Apart from the body design, the team is also working on optimizing two aspects of the bots – the motors and the solenoid. The team considered alternatives for the currently used motors while keeping within the regulations of the respective competition. The team boiled down to a set of motors, and then studied the datasheets of these motors, and selected the best fit to the team’s target of velocity and acceleration. The biggest constraint has always been the area available to include the peripherals – keeping this in mind, a vertically mount motor was considered. Also there’s being quite a lot of effort put into the development of the working of the solenoid-with the help of relevant simulating software FEMM. The main aim is to set various parameters and find out which gives the best of the results, coming to the kicking purpose of the bot where solenoid plays the key role. There has also been basic testing done into the kicking capabilities of the solenoid kicker and quite good results have been attained.
However, with FIRA around the corner, the Mechanical team’s work was complete with the hardware body design of the bots which allowed the team the time and the leverage to move on to the Robocup designs. The prototype of the chip kicker has been made and testing has begun. The team is experimenting with the various possibilities in this sector.
Going Mechanical, Headfirst into FIRA!
Mechanical Credits : Vinay Varma