Design Solutions for the “Super Gray” High Capacity Sprigger
Mickey Friedrich, Darren George, Cash Maitlen, Matt Steinert
Bermuda King L.L.C. developed the Super Gray prototype to specifically fill the needs of customers who plant large acreages, demand high planting rates, or for other reasons require a large box capacity. According to Brian Henderson, president of Bermuda King, Bermuda King L.L.C. manufactured the Super Gray prototype as an alternative to their rollback machine for increasing sprigger box capacity. This report discusses the results of our investigation as well as proposed design improvements. Expense, feasibility, and effectiveness governed the design criteria for all proposed improvements. Bermuda King petitioned the Department of Biosystems and Agricultural Engineering at Oklahoma State University in an effort to trace and resolve some performance issues of the Super Gray prototype sprigger. Upon completion of initial testing, the Department of Biosystems and Agricultural Engineering senior mechanical design team determined there was much room for improvement with regards to the machine’s planting uniformity. The prototype sprigger produced very erratic and inconsistent planting rates. It planted large clumps of sprigs in some areas while leaving other areas bare, and planting streaks across the width of the machine. In an effort to remedy the problem we conducted a series of tests and developed hypothesizes as to the cause of the problems. This outlines the solutions we propose to improve machine performance.
The Super Gray prototype has the tendency to plant inconsistent rates of Bermuda grass sprigs. Our report offers Bermuda King L.L.C. a description of the problem’s sources. The following segment examines two possible causes of the observed problems. We hypothesize that the majority of Super Gray’s problems stem from its inefficient feeding system. The feeding system governs the planting rate and uniformity of the sprigger. In the current design, the excessive lengths of the flail bar knives combined with their high rotational velocity allow the sprigger to consume large clumps of sprigs at once resulting in highly inconsistent planting rates. In addition, the substantially larger throat area of the Super Gray allows the profile of sprigs to vary as the sprigger bounces across the field. The combination of these two design features allows the actual planting rate to vary widely to both sides of the set rate.
Scope of Work
Initially review the design modifications proposed for the “Super Gray” prototype and evaluate the effectiveness of these modifications. Next, provide a detailed description of the most plausible proposed solution. This includes providing and comparing design modifications to the sprigger’s existing feed mechanism with the current design. Propose and evaluate a series of additions to the prototype to create a funnel system for the throat area of the sprigger. Finally, assess the proposed solution feasibility based upon cost, time, and the effectiveness of the modifications. In fairness, part of this evaluation includes appraising the potential problems of the proposed solution.