Hi All,

Newbie here. Just come across ExcelCalcs last week. What an amazing find. Anyway I subscribed immediately.

The Excavator Arm program was how I found the site as I am currently designing a specialise handling unit that has an arm similar to an excavator arm.

I've attached a sketch of the design proposal.

I'm not much of an Excel expert. I only know enough to get myself into trouble if you know what I mean. Anyway I was wondering if there was anybody that could let me know if it would be easy to modify the Excavator program to suit my type of design application.

As you will see from the sketch the arm only has two cylinders, a luffing cylinder for the boom and a cylinder for the dipper arm. Fitted to the end of the arm is a 3-axis manipulator with a set of clamping jaws. These wouldn't need to be part of the calculation/program. The reason a program similar to the Excavator arm would be helpful is because we are still in the very early stages of trying to establish the optimum boom and dipper arm lengths to suit the specific/desired total reach and also fit into a very confined space.
regards
Anthony Paul

As long as you can define the relationships between the geometry and dimension of the link mechanisms then it should be possible to set up an Excel workbook.

As for being easy thats an other issue. Its likely to be time consuming, depending on just how fancy you want the workbook to be. Can equally well program Acad, or use combination of Excel/VBA/Acad to model the movements.

Excel and XY charts probably easier starting point. Just think as the Excel XY chart as no different than the Acad drawing space. Then calculate points to draw lines, the shared points provide the constraints on movement.

Hi Anthony. Thanks for your kind words about the site I hope you find it helpful. I wrote the Excel Excavator sheet and I think it will be very easy to modify to optimise your particular geometry. It should be simply a matter of changing the geometry parameters.

Optimisation is always a bit of a compromise as there are a number of parameters you will be playing off against each other. Your optimisation may give the the best arm reach or alternatively lifting capacity - it depends upon your design intention.

I wrote the sheet for a course I presented to Volvo Compact Equipment. Typically excavator arms are limited by fatigue and you may also have to give some thought to this. You'll find a number of fatigue spreadsheets that will assist you with this too.

As InfoJunkie65 point out you can link the spreadsheet to a more elegant geometry tool or CAD package but I think the bulk of the preliminary work can be done with Excel. If you need any further help please fire away. You can send me a private email too.

Finally a word of caution - I should modify your forum signature and remove your email address this might make you vulnerable to spammers.